Transudate and exudate comparative characteristics. Physico-chemical properties of cavity fluids. Tumor immunology. Immune aspects of autoimmune pathology

Authors): O.Yu. KAMYSHNIKOV veterinary pathologist, “ Veterinary center pathomorphology and laboratory diagnostics of Dr. Mitrokhina N.V.”
Magazine: №6-2017

Keywords: transudate, exudate, effusion, ascites, pleurisy

Key words: transudate, exudate, effusion, ascites, pleurisy

annotation

The study of effusion fluids is currently of high importance in the diagnosis of pathological conditions. The data obtained from this study allow the clinician to obtain information about the pathogenesis of effusion formation and to correctly organize treatment measures. However, on the path of diagnosis, certain difficulties always arise that can lead to a diagnostic trap. The need for this work arose in connection with the growing need for the development and application of the method of studying effusion fluids in the clinic by clinical laboratory diagnostic doctors and cytologists. Therefore, attention will be paid to both the main tasks of laboratory doctors - to differentiate effusion into transudate and exudate, and the most important task of cytologists - to verify cellular component fluid and formulate a cytological conclusion.

Examination of effusion fluids currently has a high significance in the diagnosis of pathological conditions. The findings of this study allow the clinician to obtain information on the pathogenesis of effusion formation, and to correctly organize medical interventions. However, on the path of diagnosis, there are always certain difficulties that can lead to a diagnostic trap. The need for this work has emerged in connection with the growing need for mastering and applying the method of examining exudate fluids in the clinic by physicians of clinical laboratory diagnostics and cytologists. Therefore, attention will be paid, as well as the main tasks of laboratory assistants - to differentiate the effusion to transudate and exudate, and the most important task of cytologists is to verify the cellular component of the fluid and formulate a cytological conclusion.

Abbreviations: ES – exudate, TS – transudate, C – cytology, MK – mesothelial cells.

Background

I would like to highlight some historical data that shaped the modern image of laboratory diagnostics of effusion fluids. The study of fluids from serous cavities was used already in the 19th century. In 1875 H.J. Quincke and in 1878 E. Bocgehold pointed to such characteristic features tumor cells, such as fatty degeneration and larger size compared to mesothelial cells (MCs). The success of such studies was relatively small, since a method for studying fixed and stained preparations did not yet exist. Paul Ehrlich in 1882 and M.N. Nikiforov in 1888 described specific methods for fixing and staining biological fluids, such as blood smears, effusion fluids, discharge, etc. J.C. Dock (1897) indicated that signs of cancer cells are a significant increase in the size of the nuclei, changes in their shape and location. He also noted atypia of the mesothelium due to inflammation. The Romanian pathologist and microbiologist A. Babes created the basis of the modern cytological method using azure dyes. Further development of the method occurred together with the entry into practical medicine laboratory diagnostics, which in our country included cytologists among its specialists. Clinical cytology in the USSR as a method of clinical examination of patients began to be used in 1938 by N.N. Schiller-Volkova. The development of clinical laboratory diagnostics in veterinary medicine occurred with a significant lag, so the first fundamental work of domestic doctors and scientists in this field of knowledge was published only in 1953–1954. It was a three-volume volume “Veterinary Research Methods in Veterinary Medicine” edited by prof. S.I. Afonsky, Doctor of V.S. MM. Ivanova, prof. Ya.R. Kovalenko, where for the first time laboratory diagnostic methods, undoubtedly extrapolated from the field of human medicine, were clearly presented. From those ancient times to the present, the method of studying effusion fluids has been constantly improved, based on the foundation of previously acquired knowledge, and now occupies an integral part of any clinical diagnostic laboratory study.

In this work, an attempt is made to highlight the basics and essence of the laboratory study of effusion fluids.

general characteristics

Exudate fluids are components of blood plasma, lymph, and tissue fluid that accumulate in serous cavities. According to the generally accepted belief, effusion is fluid in the body cavities, and edematous fluid accumulates in tissues according to the same principle. Serous body cavities are a narrow gap between two layers of the serous membrane. Serous membranes are films originating from the mesoderm, represented by two layers: parietal (parietal) and visceral (organ). The microstructure of the parietal and visceral layer is represented by six layers:

1. mesothelium;

2. limiting membrane;

3. superficial fibrous collagen layer;

4. superficial non-oriented network of elastic fibers;

5. deep longitudinal elastic network;

6. deep lattice layer of collagen fibers.

Mesothelium is a single-layer squamous epithelium consisting of polygonal cells tightly adjacent to each other. Despite its epithelial shape, the mesothelium is of mesodermal origin. Cells are very diverse in their morphological properties. Binucleate and trinucleate cells can be observed. The mesothelium constantly secretes a fluid that performs a sliding and shock-absorbing function, is capable of extremely intense proliferation, and exhibits the characteristics connective tissue. On the surface of the urinary tract there are many microvilli, increasing the surface of the entire membrane of the serous cavity by approximately 40 times. The fibrous layer of connective tissue of the serous membranes determines their mobility. The blood supply to the serous membrane of the visceral layer is carried out by the vessels of the organ that it covers. And for the parietal leaf, the basis of the circulatory system is a wide-loop network of arterio-arteriolar anastomoses. The capillaries are located immediately under the mesothelium. Lymphatic drainage from the serous membranes is well developed. Lymphatic vessels communicate with serous spaces thanks to special openings - stomata. Because of this, even minor blockage of the drainage system can lead to the accumulation of fluid in the serous cavity. And the anatomical properties of the blood supply lead to the rapid occurrence of bleeding when the mesothelium is irritated and damaged.

Clinical laboratory diagnosis of effusion fluids

During a laboratory study, the question of whether the effusion is a transudate or an exudate is resolved, and the general properties (macroscopic appearance of the liquid) are assessed: color, transparency, consistency.

Fluid that accumulates in the serous cavities without an inflammatory reaction is called transudate. If fluid collects in the tissues, then we are dealing with edema ( edema). Transudate may accumulate in the pericardium ( hydropericardium), abdominal cavity ( ascites), pleural cavity ( hydrothorax), between the membranes of the testicle ( hydrocele). The transudate is usually transparent, almost colorless or with a yellowish tint, less often slightly cloudy due to the admixture of desquamated epithelium, lymphocytes, fat, etc. The specific gravity does not exceed 1.015 g/ml.

The formation of transudate can be caused by the following factors.

By increasing venous pressure, which occurs with circulatory failure, kidney disease, and cirrhosis of the liver. Transudation is the result of an increase in the permeability of capillary vessels as a result of toxic damage, hyperthermia, and nutritional disorders.
Reducing the amount of protein in the blood, osmotic pressure colloids decreases when plasma albumin decreases to less than 25 g/l (nephrotic syndrome of various etiologies, severe liver damage, cachexia).
blockage lymphatic vessels. In this case, chylous edema and transudates are formed.
Violations of electrolyte metabolism, mainly increased sodium concentration (hemodynamic heart failure, nephrotic syndrome, cirrhosis of the liver).
Increased aldosterone production.

In one phrase, the formation of a transudate can be characterized as follows: a transudate occurs when hydrostatic or colloid-osmotic pressure changes to the extent that the fluid filtered into the serous cavity exceeds the volume of reabsorption.

The macroscopic characteristics of exudates make it possible to classify them as the following types.

1. Serous exudate may be clear or cloudy, yellowish or colorless (as determined by the presence of bilirubin), varying degrees turbidity (Fig. 1).

2. Serous-purulent and purulent exudate - a cloudy, yellowish-green liquid with abundant loose sediment. Purulent exudate occurs with pleural empyema, peritonitis, etc. (Fig. 2).

3. Putrid exudate – a cloudy liquid of gray-green color with a pungent putrefactive odor. Putrid exudate is characteristic of lung gangrene and other processes accompanied by tissue breakdown.

4. Hemorrhagic exudate - a clear or cloudy liquid, reddish or brownish-brown in color. The number of red blood cells can vary: from a small admixture, when the liquid has a faint pink color, to abundant, when it looks like whole blood. Most common cause hemorrhagic effusion is a neoplasm, but the hemorrhagic nature of the fluid does not have much diagnostic significance, since it is also observed in a number of non-tumor diseases (trauma, pulmonary infarction, pleurisy, hemorrhagic diathesis). At the same time, in malignant processes with extensive dissemination of the tumor along the serous membrane, there may be a serous, transparent effusion (Fig. 3).

5. Chylous exudate is a milky, turbid liquid containing tiny fat droplets in suspension. When ether is added, the liquid becomes clear. Such an effusion is caused by lymph entering the serous cavity from destroyed large lymphatic vessels, an abscess, vascular infiltration by a tumor, filariasis, lymphoma, etc. (Fig. 4).

6. Chyle-like exudate is a milky-turbid liquid that appears as a result of abundant breakdown of cells with fatty degeneration. Since, in addition to fat, this exudate contains big number fat-degenerated cells, the addition of ether leaves the liquid cloudy or slightly clears it. Chyle-like exudate is characteristic of effusion fluids, the appearance of which is associated with atrophic cirrhosis of the liver, malignant neoplasms, etc.

7. Cholesterol exudate is a thick yellowish or brownish liquid with a pearlescent tint with shiny flakes consisting of clusters of cholesterol crystals. An admixture of destroyed red blood cells can give the effusion a chocolate tint. On the walls of the test tube, moistened with effusion, casts of cholesterol crystals in the form of tiny sparkles are visible. This is the character of an encysted effusion that exists for a long time (sometimes for several years) in the serous cavity. Under certain conditions - reabsorption of water and some mineral components of the exudate from the serous cavity, as well as in the absence of fluid influx into the closed cavity - exudate of any etiology can acquire the character of cholesterol.

8. Mucous exudate – contains a significant amount of mucin and pseudomucin, can occur with mesothelioma, mucus-forming tumors, pseudomyxoma.

9. Fibrinous exudate – contains a significant amount of fibrin.

There are also mixed forms of exudate (sero-hemorrhagic, muco-hemorrhagic, serous-fibrinous).

In native effusion fluid, it is necessary to conduct a cytosis study. To do this, immediately after puncture, the liquid is taken into a tube with EDTA to prevent it from clotting. Cytosis, or cellularity (in this method only the number of nucleated cells is determined) is carried out according to standard methods in a Goryaev chamber or on a hematological analyzer in counting mode whole blood. The number of nuclear cells is taken to be the WBC (white blood cell, or leukocyte) value in thousands of cells per milliliter of liquid.

After determining the cytosis, the liquid can be centrifuged to obtain a sediment for microscopic examination. The supernatant, or supernatant, can also be tested for protein, glucose, etc. content. However, not all biochemical parameters can be determined from a liquid with EDTA, therefore it is also recommended that, along with taking the effusion into a test tube with an anticoagulant, simultaneously taking the liquid into a clean, dry test tube (for example, a centrifuge or biochemical research). It follows that to study effusion fluid in the laboratory, it is necessary to obtain the material in at least two containers: a test tube with EDTA and a clean dry test tube, and the liquid must be placed there immediately after its evacuation from the body cavity.

The sediment is examined in the laboratory by a laboratory assistant or a cytologist. To sediment the effusion fluid, it is necessary to centrifuge it at 1500 rpm for 15–25 minutes. Depending on the type of effusion, a precipitate of varying quantity and quality is formed (it can be grayish, yellowish, bloody, single- or double-layered, and occasionally three-layered). In a serous transparent effusion, there may be very little sediment, its character is fine-grained, and the color is grayish-white. In a turbid purulent or chylous effusion with a large number of cells, a copious, coarse-grained sediment is formed. In hemorrhagic effusion with a large admixture of red blood cells, a two-layer sediment is formed: the upper layer in the form of a whitish film and the lower in the form of a dense accumulation of red blood cells. And when the sediment is divided into 3 layers, the upper one is often represented by a component of destroyed cells and detritus. When preparing smears on glass slides, material from the sediment is taken from each layer and at least 2 smears are prepared. For a single-layer deposit, it is recommended to make at least 4 glasses. If the amount of sediment is scanty, 1 smear is prepared with the maximum amount of material in it.

Smears dried in air at room temperature are fixed and stained with azure-eosin according to the standard method (Romanovsky-Giemsa, Pappenheim-Kryukov, Leishman, Nocht, Wright, etc.).

Differential diagnosis of transudates and exudates

To differentiate transudate from exudate, you can use several methods, which are based on determining the physical and biochemical parameters of the liquid. The distinction is based on protein content, cell type, color of the liquid and its specific gravity.

Transudate, in contrast to exudate, is an effusion of non-inflammatory origin, and it is fluid that accumulates in body cavities as a result of the influence of systemic factors regulating homeostasis on the formation and resorption of fluid. The specific gravity of transudate is lower than that of exudates and is less than 1.015 g/ml versus 1.015 or more for exudates. The total protein content of transudates is less than 30 g/l versus a value exceeding 30 g/l for exudates. There is a high-quality test that allows you to verify transudate from exudate. This is the well-known Rivalta test. It entered laboratory practice more than 60 years ago and occupied an important place in the diagnosis of effusion fluids until the development of biochemical methods and their simplification and accessibility, which made it possible to move from qualitative method Rivalta samples to quantitative characteristics protein content. However, now many researchers are proposing to use the Rivalta test to quickly and fairly accurately obtain data on effusion. Therefore, it is necessary to describe this sample a little.

Rivalta sample

In a narrow cylinder with a weak solution acetic acid(100 ml of distilled water + 1 drop of glacial acetic acid) add the test effusion liquid drop by drop. If this drop, falling down, gives a streak of turbidity trailing behind it, then the liquid is an exudate. Transudates do not give a positive test or give a weakly positive short-term turbidity reaction.

“Cytological Atlas of Dogs and Cats” (2001) R. Raskin and D. Meyer propose to distinguish the following types of serous fluids: transudates, modified transudates and exudates.

Modified transudate is a transitional form from transudate to exudate, containing “intermediate values” of protein concentration (between 25 g/l and 30 g/l) and specific gravity (1.015–1.018). In modern Russian literature, the term “modified transudate” is not used. However, the formulations “more data for transudate” or “more data for exudate” are allowed based on the results of the differential characteristics parameters.

In table Table 1 shows the parameters, the determination of which allows one to verify transudate from exudate.

Table 1. Differential characteristics of transudates and exudates

	Transudates	Exudates
Specific gravity, g/ml		more than 1,018
Protein, g/l	less than 30 g/l	more than 30 g/l
Clotting	usually absent	usually happens
Bacteriology	Sterile or contain “travel” microflora	Microbiological examination reveals microflora (streptococci, staphylococci, pneumococci, E. coli, etc.)
Sediment cytology	Mesothelium, lymphocytes, sometimes erythrocytes (“travel”)	Neutrophils, lymphocytes, plasma cells, macrophages and red blood cells in abundance, eosinophils, reactive mesothelium, tumor cells
Total protein effusion/serum ratio
LDH, ratio LDH effusion/LDH serum
Glucose concentration, mmol/l	more than 5.3 mmol/l	less than 5.3 mmol/l
Cholesterol concentration, mmol/l	less than 1.6 mmol/l	more than 1.6 mmol/l
Cytosis (nucleated cells)	less than 1×10 9 /l	more than 1×10 9 /l

Microscopic examination of exudates

Description of cytograms of effusion fluids

In Fig. Figure 5 shows a micrograph of the reactive effusion sediment. In the sediment, mesothelial cells are observed, often binucleate, with abundant intensely basophilic cytoplasm and rounded hyperchromatic nuclei. The edge of the cytoplasm is uneven, villous, often with a sharp transition from basophilic to bright oxyphilic staining along the edge of the cell. The nuclei contain dense compact heterochromatin; nucleoli are not visible. Macrophages and segmented neutrophils are present in the microenvironment. The background of the drug is not determined.

In Fig. Figure 6 shows a micrograph of the reactive effusion sediment. Macrophages are observed in the sediment (the figure shows 2 cells in close proximity). Cells irregular shape, have abundant inhomogeneous “lacey” cytoplasm with many vacuoles, phagosomes, and inclusions. The cell nuclei are irregular in shape and contain delicately reticulated and looped chromatin. Remnants of nucleoli are visible in the nuclei. There are 2 lymphocytes in the microenvironment. The background of the preparation contains red blood cells.

In Fig. Figure 7 shows a micrograph of the reactive effusion sediment. Mesothelial cells with pronounced signs reactive changes: hyperchromia of both the cytoplasm and nuclei, swelling of the cytoplasm, mitotic figures. Macrophages in the microenvironment have signs of erythrophagocytosis, which is often observed in acute hemorrhages in the serous cavities.

In Fig. Figure 8 shows a micrograph of the sediment of the reactive inflammatory effusion. Macrophages, lymphocytes and segmented neutrophils with signs of degenerative changes are observed in the sediment. Degenerative changes in neutrophils are regarded as an indicator of the duration of inflammation and the activity of the inflammatory reaction. The “older” the inflammation, the more pronounced the degenerative signs. How more active process, the more often typical cells are found against the background of altered neutrophils.

A big problem in the interpretation of cytograms is created by mesothelial cells, which are capable, under the influence of unfavorable factors and irritation, of acquiring signs of atypia, which can be mistakenly taken for signs of malignancy.

The criteria for malignancy (atypia) of cells in the effusion are shown in comparison in Table. 2.

Table 2. Distinctive features reactive mesothelial cells and malignant neoplasm cells.

Malignant tumors of the serous membranes can be primary (mesothelioma) and secondary, i.e. metastatic.

Common metastases malignant tumors along the serous membranes:

1. for the pleural and abdominal cavity – breast cancer, lung cancer, cancer of the gastrointestinal tract, ovaries, testes, lymphoma;

2. for the pericardial cavity - most often lung and breast cancer.

It is possible that metastases of squamous cell carcinoma, melanoma, etc. may also be detected in the serous cavities of the body.

In Fig. Figure 9 shows a micrograph of a sediment of effusion fluid when the abdominal cavity is affected by metastases of glandular cancer. In the center of the microphoto, a multilayered complex of atypical epithelial cells is visible - metastasis of glandular breast cancer. The boundaries between cells are indistinguishable, the hyperchromic cytoplasm hides the nuclei. The background of the preparation contains red blood cells and inflammatory cells.

In Fig. Figure 10 shows a micrograph of a sediment of effusion fluid when the abdominal cavity is affected by metastases of glandular cancer. In the center of the microphotograph a spherical structure of atypical epithelial cells is visualized. The complex of cells has a glandular structure. The boundaries of neighboring cells are indistinguishable. Cell nuclei are characterized by moderate polymorphism. The cytoplasm of the cells is moderate, intensely basophilic.

In Fig. Figures 11 and 12 show microphotographs of effusion fluid sediment when the pleural cavity is affected by metastases of glandular cancer. The figures show complexes of atypical polymorphic cells of epithelial origin. The cells contain large polymorphic nuclei with fine-grained dispersed chromatin and 1 large nucleolus. The cytoplasm of the cells is moderate, basophilic, containing fine oxyphilic granules - signs of secretion.

In Fig. Figure 13 shows a micrograph of a sediment of effusion fluid when the abdominal cavity is affected by metastases of glandular cancer. The microscope is shown at low magnification - the cell complex is very large. And in Fig. Figure 14 shows a more detailed structure of cancer cells. The cells form a glandular complex - the clearing of the noncellular component in the center of the complex is surrounded by rows of atypical tumor epithelial cells.

Forming a conclusion about the belonging of the found tumor cells to the primary focus is possible on the basis of anamnesis data and the specific structure of the cells and their complexes. With an undetected primary tumor focus, lack of medical history, low cell differentiation, and severe atypia, it is difficult to determine the tissue affiliation of tumor cells.

Rice. 15 shows a giant atypical cancer cell in the effusion fluid. The primary focus in this case was not identified. The cell contains a large, “bizarrely shaped” nucleus, moderate basophilic cytoplasm with inclusions and the phenomenon of empiriopolosis.

When lymphoma disseminates along the serous membranes, many atypical lymphoid cells will enter the effusion (Fig. 16). These cells are often of the blast cell type and are distinguished by polymorphism and atypia: they contain polymorphic nucleoli, have an uneven karyolemma with depressions, and uneven chromatin (Fig. 17).

Mesothelioma creates significant difficulties at the stage of diagnosing damage to the serous membranes by malignant tumors.

Mesothelioma is a primary malignant neoplasm of the serous membranes. According to statistics, it is more common in the pleural than in the peritoneal cavity. Mesothelioma is extremely difficult for histological and even more so cytological diagnosis, since it becomes necessary to differentiate it from reactive mesothelium and from almost all possible types of cancer found in serous cavities.

In Fig. Figures 18–19 show micrographs of mesothelioma cells in the effusion. The cells are distinguished by severe atypia, polymorphism, and gigantic size. However, the morphological characteristics of mesothelial cells are so diverse that without extensive practical experience it is almost impossible for a cytologist to “recognize” mesothelioma.

Conclusion

Based on the above, we can conclude that cytological examination of exudates from serous cavities is the only method for diagnosing the nature of the effusion. And the routine examination of effusion fluids when determining whether they belong to exudate should be supplemented by a cytological examination of the sediment.

Literature

1. Abramov M.G. Clinical cytology. M.: Medicine, 1974.

2. Balakova N.I., Zhukhina G.E., Bolshakova G.D., Mochalova I.N. Fluid testing

from serous cavities. L., 1989.

3. Volchenko N.N., Borisova O.V. Diagnosis of malignant tumors by serous exudates. M.: GEOTAR-Media, 2017.

4. Dolgov V.V., Shabalova I.P. and etc. Exudate fluids. Laboratory research. Tver: Triad, 2006.

5. Klimanova Z.F. Cytological examination of exudates in metastatic lesions of the peritoneum and pleura by cancer: Guidelines. M., 1968.

6. Kost E.A. Handbook of Clinical Laboratory Methods. M.: Medicine, 1975.

7. Guide to the cytological diagnosis of human tumors. Ed. A.S. Petrova, M.P. Ptokhova. M.: Medicine, 1976.

8. Strelnikova T.V. Exudate fluids (analytical review of the literature). RUDN University Bulletin, series: Agronomy and livestock breeding. 2008; 2.

9. Raskin R.E., Meyer D.J. Atlas of canine and feline cytology. W.B. Sanders, 2001.

Determination of physicochemical properties

Determination of the physicochemical properties of pleural effusion begins with assessing the appearance of the resulting material and determining its color, transparency, consistency and odor. Based on these signs, several types of pleural effusion can be distinguished:

Transudate is a non-inflammatory effusion in the pleural cavity, formed as a result of an increase in hydrostatic pressure (right ventricular or biventricular heart failure) or a decrease in colloid-osmotic pressure of the blood plasma (nephrotic syndrome with glomerulonephritis, renal amyloidosis and lipoid nephrosis, with cirrhosis of the liver with a violation of its protein-synthetic functions, etc.). By appearance transudate is a transparent, yellowish, odorless liquid.

Exudates - pleural effusion of inflammatory origin (infectious and non-infectious origin). All exudates are different high content protein, in particular fibrinogen, and high relative density. The appearance of the exudate depends on the nature of the inflammatory process in the pleura, the cellular composition of the pleural fluid and some other factors.

There are several main types of exudates:

Serous exudate is a transparent yellowish liquid, odorless, very similar in appearance to transudate. In patients with pleural effusions of various etiologies, serous exudate occurs in 70% of cases (N.S. Tyukhtin). The most common causes of serous exudate are tuberculosis, pneumonia and tumors.

Purulent exudate is cloudy (due to the abundance of leukocytes), yellowish-greenish or grayish-white in color, thick, creamy consistency, usually odorless. Purulent exudate is usually detected in pleurisy caused by bacterial flora. In case of gangrene or lung abscess, complicated by putrefactive pleural effusion, the latter acquires an unpleasant fetid odor, which is caused by the breakdown of protein under the influence of anaerobic bacteria.

Hemorrhagic exudate. Depending on the admixture of blood and the duration of its stay in the pleural cavity, it has a bloody color of varying intensity - from pink transparent to dark red and brown, turbid liquid and contains a significant admixture of changed and unchanged red blood cells. With their hemolysis, the exudate acquires a peculiar varnish appearance. Hemorrhagic exudate is more often observed in pleural effusions associated with a tumor process in the pleura and lung (primary pleural tumor - mesothelioma, tumor metastases in the pleura), with traumatic pleurisy and tuberculosis. Less commonly, various variants of hemorrhagic effusion, including serous-hemorrhagic, are detected in pneumonia and other diseases.

Chylous and chyle-like exudates are a cloudy whitish liquid that resembles milk in appearance due to its high fat content. Chylous exudates are formed when the outflow of lymph through the thoracic lymphatic duct is obstructed due to compression by a tumor, enlarged lymph nodes, or when the duct is ruptured (trauma, tumor). Chyle-like exudates also contain a large amount of fat, but not due to the admixture of lymph (chyle), but due to the abundant breakdown of cells undergoing fatty degeneration, which is more often observed with chronic inflammation serous membranes.

Cholesterol exudates are a thick liquid with a dark yellowish or brownish tint and are usually found in chronic encysted effusions several years old.

Transudates and serous exudates are transparent and have a characteristic slightly yellowish color. Purulent, hemorrhagic, chylous, chyle-like and cholesterol exudates are in most cases cloudy and differ in color from transudates and serous exudates.

Table 6.2 presents some important diagnostic features that can be identified by macroscopic examination of the pleural contents.

table 2 .

Diagnostic value of some macroscopic signs of pleural effusion

Signs	Diagnostic value
Blood in pleural effusion	Tumor pleurisy (about 44%) Post-traumatic pleurisy Tuberculous pleurisy Parapneumonic pleurisy, etc.
White color of effusion	Chylous effusion Chylous effusion Cholesterol effusion
Chocolate syrup color	Amoebic liver abscess with rupture into the pleural cavity
Black color	Effusion due to aspergillosis
Yellowish-greenish effusion	Pleurisy in rheumatoid arthritis
	Empyema of the pleura
Putrid smell	Pleural empyema (anaerobic pathogens)
Very high viscosity of the effusion	Mesothelioma
Ammonia smell	Uremic effusion

Laboratory research of the physicochemical properties of pleural effusions in most cases makes it possible to differentiate transudate and exudate.

Relative density transudates range from 1.002 to 1.015, and exudates - above 1.018.

Protein. Transudates contain no more than 5-25 g/l of protein, exudates - from 30 g/l or more. Purulent exudates have a particularly high concentration of protein (up to 70 g/l). The ratio of pleural effusion protein to serum protein is often determined. (proteincoefficient). Transudates are characterized by a relatively low protein coefficient (below 0.5). Exudates have a higher ratio (>0.5).

Rivalta sample used to approximate the difference between exudates and transudates. It is based on the fact that when a drop of exudate with a relatively high protein concentration is added to a solution of acetic acid, it becomes cloudy (Fig. 32). Distilled water is poured into a 100 ml cylinder and acidified with 2-3 drops of glacial acetic acid. Then the test liquid is added dropwise to the cylinder. If at the same time a peculiar cloudiness of the solution appears in the form of a white cloud falling to the bottom of the cylinder (Fig. 32, a), the sample is considered positive, which is typical for exudate. If the falling drops quickly and completely dissolve (Fig. 32, b), the sample is regarded as negative(transudate).

Rice. 32. Positive (a) and negative (b) Rivalta test.

Glucose. Determination of glucose content in pleural effusion is carried out simultaneously with the study of glucose concentration in the blood. A decrease in the ratio of glucose levels in pleural fluid to blood below 0.5 is characteristic of exudates, which often indicates a blockage of glucose transfer into the pleural effusion. In addition, in the focus of inflammation, under the influence of polymorphonuclear leukocytes and bacteria, activation of anaerobic glucose metabolism occurs, which is accompanied by a decrease in the concentration of glucose in the pleural cavity, the formation of lactic acid and carbon dioxide. A decrease in glucose levels below 3.3 mmol/l occurs in tuberculosis, rheumatoid arthritis, malignant tumors, pneumonia (parapneumonic effusion), rupture of the esophagus, as well as in the early stages of acute lupus pleurisy. The most pronounced decrease in glucose concentration is observed with the development of purulent pleurisy (pleural empyema).

Decrease pH pleural fluid levels below 7.3 are detected under the same pathological conditions. The pH value of pleural effusion usually correlates well with decreased glucose levels. A decrease in the pH of the pleural fluid during purulent-inflammatory and non-infectious pleurisy is due to increased anaerobic metabolism of glucose, as a result of which the content of lactic acid and CO 2 increases and acidosis develops.

Lactate dehydrogenase (LDH) activity allows you to roughly estimate the intensity of the inflammatory process in the pleura. Exudates are generally characterized by a high level of LDH (more than 1.6 mmol/l x h), and transudates are characterized by a low level (less than 1.6 mmol/l x h). Sometimes the so-called enzyme coefficient - the ratio of the LDH content of the effusion to the LDH content of the blood serum, which in exudates exceeds 0.6, and in transudates - less than 0.6.

Thus, determining the physicochemical properties of pleural effusion in most cases (although not always) makes it possible to differentiate transudate and exudate, the most characteristic differences of which are presented in Table 6.3.

Remember: For transudates characterized by low relative density (1.002-1.015), low protein content (up to 25 g/l), low LDH activity (3.3 g/l), negative Rivalta test, decreased protein (

Exudates are characterized by higher relative density (> 1.018) and protein content (30 g/l and above), high LDH activity (> 1.6 mmol/l x h), decreased glucose (0.5) and enzyme (> 0.6) coefficients.

It should be added that a high level of amylase in the pleural fluid is characteristic of effusions caused by diseases of the pancreas - acute or exacerbation of chronic pancreatitis. In addition, increased amylase in the pleural fluid occurs with ruptures of the esophagus and (very rarely) with adenocarcinoma of the lung. It is characteristic that in these cases the level of amylase in the pleural effusion is higher than in the blood serum.

Immunological studies pleural contents make it possible to detect the causative agent of the disease and/or antibodies to it. For this purpose, highly informative enzyme immunoassays and polymerase chain reaction (PCR) are usually used.

Table 3.

The main differences between transudate and exudate

Indicators	Transudate	Exudate
Relative density Exudate pH
Relative density Exudate pH

“Protein ratio” - ratio: effusion protein / serum protein
Rivalta sample	Negative	Positive
Fibrinogen	Present	There is no cavity at different pathological conditions effusion), for puncture drainage of encysted formations... strips of bronchi. Adjacent pleura becomes denser, in some cases it is found effusion V pleural cavities. Resolution stage... Tumor immunology. Immune aspects of autoimmune pathology Abstract >> Medicine, health Patients with SLE and rheumatoid arthritis in pleural and pericardial effusion the hemolytic activity of complement is reduced. d. ... observed pleurisy, manifested by pain in the side when breathing and pleural sweat. Subsequently there may be pleural adhesions... Therapeutic physical training for respiratory diseases Abstract >> Physical education and sports ... pleural effusions, often accompanying lung diseases and pleura, formed in pleural cavity fluid and irritation of nerve prescriptions in pleural ...

Serous fluid accumulates in pleural cavities(pleural fluid), peritoneal cavity (ascitic fluid), in the pericardial cavity (pericardial fluid) and is removed by puncture or incision of these cavities. To prevent coagulation, you can add a 5% sodium citrate solution to the test liquid (2-5 ml of solution per 100 ml of liquid) or rinse the walls of the vessel into which the serous liquid will be collected with this solution. For testing, all collected serous fluid is sent to the laboratory in clean containers. Depending on the mechanism of formation, two types of serous fluid are distinguished - transudate and exudate.

Transudate

Transudate (non-inflammatory fluid) appears when there are disorders of the general and local circulation(right ventricular failure of the heart, portal hypertension due to portal vein thrombosis, cirrhosis of the liver, adhesive pericarditis, etc.), decreased oncotic pressure in the vessels (hypoproteinemia of various origins), impaired electrolyte metabolism (most often with increased sodium concentration, increased aldosterone production) and etc. Transudate is usually light yellow in color, transparent, its relative density ranges from 1005-1015 (determined in the same way as the relative density of urine, i.e., by a urometer). The amount of protein in the serous fluid is determined by the turbidity formed when sulfosalicylic acid is added or by the Brandberg-Roberts-Stolnikov method. The transudate contains from 5 to 10 g/l of protein.

Exudate

Exudate is an inflammatory fluid. Serous exudate is light yellow in color and transparent. In all other cases, the exudate is cloudy, and its color depends on the nature (bloody, purulent, etc.). The relative density of the exudate is 1.018 and higher. It contains from 30 to 80 g/l of protein.

It is not always easy to distinguish between transudate and exudate, since there are liquids that are similar in their properties to both exudate and transudate, and exudate with a low relative density and a relatively low protein content. To differentiate these liquids, the Rivalta reaction is used.

Methodology. A narrow cylinder with a capacity of 200 ml is filled with water, 2-3 drops of glacial acetic acid are added and stirred. Then, add 1-2 drops of the test liquid from a pipette into the resulting weak solution of acetic acid and watch on a black background for the appearance of a cloud-like cloudiness, reminiscent of cigarette smoke. In the exudate, the turbidity increases as the drop descends and reaches the bottom of the cylinder (positive reaction); in the transudate, slight turbidity dissipates and disappears before reaching the bottom of the cylinder (negative reaction).

After settling the serous fluid delivered for examination for

After 1-2 hours, the sediment is collected with a glass tube for centrifugation (as when examining urine). If there is a lot of liquid, then the sediment is collected in several centrifuge tubes (up to 10). After centrifugation for 5-10 minutes at 1500-3000 rpm, all the resulting sediments are poured into one test tube and centrifuged again. As a result, a concentrated sediment is obtained, from which native preparations are prepared for microscopic examination.

If there are fibrinous convolutions, shreds or clots in the liquid, then their quantity and volume are described in the analysis. The bundles and scraps are selected with a narrow spatula and a needle from the liquid poured into a Petri dish, and then pieces are split off from them for the preparation of native preparations, since the formed elements are usually found in the bundle. The bundle placed on a glass slide is stretched with a needle and spatula. Otherwise, the result will be a thick preparation, unsuitable for microscopic examination (the shaped elements will be indistinguishable in it).

After microscopic examination, native preparations are stained according to Romanovsky - Giemsa or Pappenheim. Painting time - no more than 5 minutes. In the presence of serous fluid of pus, smears are prepared from the sediment for Ziehl-Neelsen and Gram staining.

Types of exudate

Depending on the type of pathological process, different types of exudate are distinguished.

Serous and serous-fibrinous exudate

Serous and serous-fibrinous exudate is observed with staphylococcal, streptococcal infections, tuberculosis, syphilis, rheumatism. Fibrinous clots are usually present in serous-fibrinous exudate. Microscopy reveals a small number of cellular elements. Lymphocytes predominate. Sometimes a significant number of either neutrophilic granulocytes, or monocytes, or macrophages, or eosinophilic granulocytes, or all of these elements in any ratio is detected. In prolonged forms of pleurisy, the cytogram is characterized by the presence of plasma cells. Often, at the beginning of tuberculous pleurisy, a variegated cytogram pattern is revealed (eosinophilic and neutrophilic granulocytes, histiocytes, elements of tuberculoma, etc.), due to which it sometimes has to be differentiated from lymphogranulomatosis.

Serous-purulent and purulent exudate

Serous-purulent and purulent exudate is cloudy, thick, green-yellow, sometimes brownish or chocolate-colored; observed when bacterial infection. Cytograms are characterized by a large number of neutrophilic granulocytes, often with degenerative changes, the presence of macrophages, single giant cells of foreign bodies and detritus.

Putrid exudate

Putrid exudate has a putrid odor and a greenish color. In cytograms there is a large amount of detritus of disintegrated cells, needles of fatty acids, sometimes crystals of hematoidin and cholesterol are found, and many microorganisms, including anaerobic ones.

Eosinophilic exudate

Eosinophilic exudate is characterized by a large number of eosinophilic granulocytes, which can reach more than 90% of the cellular composition of the effusion. It is sometimes observed with tuberculosis or other infections, abscess, trauma, multiple metastases of cancer in the lungs, migration of roundworm larvae into the lungs, etc. By nature, eosinophilic exudate can be serous, hemorrhagic and purulent.

Hemorrhagic exudate

Hemorrhagic exudate appears with mesothelioma, cancer metastases, hemorrhagic diathesis, and chest wounds. When infection penetrates into the cavity with hemorrhagic exudate, it can turn into purulent-hemorrhagic. An admixture of pus in the exudate is detected using Petrov's test: when water is added, the sterile exudate becomes clear due to hemolysis of red blood cells, while the infected remains cloudy due to the presence of leukocytes.

During microscopic examination, attention is paid to red blood cells. If the bleeding has already stopped, then only old forms of erythrocytes can be identified with various signs of their death (microforms, “mulberries”, shadows of erythrocytes, poikilocytes, schizocytes, vacuolated, fragmented erythrocytes, etc.). The appearance of unchanged red blood cells against the background of old, changed ones indicates re-bleeding. The presence of only unchanged red blood cells indicates fresh bleeding. When hemorrhagic exudate transforms into purulent or another form, corresponding cellular elements appear. During the period of resorption of hemorrhagic exudate, sometimes up to 80% of its cellular elements are eosinophilic granulocytes, which is a favorable sign.

Cholesterol exudate.

Any encysted exudate that persists for a long time (several years) can turn into cholesterol. Cholesterol exudate is thick, yellowish or brownish in color, with a pearlescent sheen, sometimes chocolate-colored (depending on the number of disintegrated red blood cells). On the walls of a test tube moistened with exudate, casts of cholesterol crystals in the form of tiny sparkles are macroscopically visible. Microscopic examination reveals fatty-degenerated cells, cellular decay products, fat droplets and cholesterol crystals.

Milky exudate.

There are three types of such exudate.

Chylous exudate appears when a significant amount of lymph enters the serous cavity from large lymphatic vessels. This liquid contains a large number of small droplets of fat, which is stained red by Sudan III and black by osmium. When standing in the liquid, a creamy layer forms and floats to the top.

To clarify the liquid, add 1-2 drops of caustic alkali with ether to the exudate. Depending on the cause that caused the rupture of the lymphatic vessel, the cellular elements of the exudate may be different. If a tumor has grown into a vessel and destroyed it, then tumor cells can be found in the fluid.

Chyle-like exudate observed with intensive breakdown of fatty degenerated cells. Microscopic examination reveals an abundance of fatty-degenerated cells, fatty detritus and fatty droplets of various sizes. There is no microflora. Chyle-like exudate is observed in chronic purulent pleurisy, atrophic cirrhosis of the liver, malignant neoplasms and etc.

Pseudochyle exudate macroscopically also resembles milk, but particles suspended in the exudate are not stained by Sudan III and osmium and do not dissolve when heated. Microscopy reveals mesotheliocytes and single fat droplets. Pseudochyle exudate occurs in lipoid and lipoid-amyloid degeneration of the kidneys.

Guide to practical exercises in clinical laboratory diagnostics/ Ed. prof. M.A. Bazarnova, prof. V.T. Morozova.- K.: Vyshcha School, 1988.- 318 p., 212 ill.

Transudate I Transudate (lat. trans through, through + sudare to ooze, leak)

edematous fluid accumulating in body cavities and tissue crevices. T. is usually colorless or pale yellow, transparent, less often cloudy due to the admixture of single cells of deflated epithelium, lymphocytes, and fat. The protein content in T. usually does not exceed 3%; they are serum albumins and globulins. Unlike exudate, there are no exudates characteristic of plasma in T. The relative density of transudate is 1.006-1.012, and that of exudate is 1.018-1.020. Sometimes the qualitative differences between T. and exudate disappear: T. becomes cloudy, the amount of protein in it increases to 4-5%). In such cases, the study of the entire complex of clinical, anatomical and bacteriological changes (the presence of pain in the patient, elevated temperature body, inflammatory hyperemia, hemorrhages, detection of microorganisms in liquid). To distinguish transudate from exudate, the Rivalta test is used, based on their different protein content.

T. formation is most often caused by heart failure (Heart failure) , portal hypertension (Portal hypertension) , lymph stagnation, venous thrombosis, renal failure(Kidney failure) . The mechanism of occurrence of T. is complex and is determined by a number of factors: increased hydrostatic pressure of the blood and reduced colloid-osmotic pressure of its plasma, increased permeability of the capillary wall, and retention of electrolytes, mainly sodium and water, in the tissues. The accumulation of T. in the pericardial cavity is called Hydropericardium , in the abdominal cavity - Ascites , in the pleural - Hydrothorax , in the cavity of the testicular membranes (testicle) - hydrocele, in the subcutaneous tissue - anasarca. T. is easily infected, turning into. Thus, ascites leads to the occurrence of peritonitis (ascites-peritonitis). With prolonged accumulation of edematous fluid in the tissues, atrophy of parenchymal cells and sclerosis also develop. . If the process progresses favorably, T. may resolve.

II Transudate (transsudatum; Trans- + lat. sudo, sudatum sweat, ooze; edematous fluid)

protein-poor liquid that accumulates in tissue crevices and body cavities during edema.

1. Small medical encyclopedia. - M.: Medical encyclopedia. 1991-96 2. First health care. - M.: Great Russian Encyclopedia. 1994 3. encyclopedic Dictionary medical terms. - M.: Soviet Encyclopedia. - 1982-1984.

Synonyms:

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Transudate... Spelling dictionary-reference book

- (lat.). The fluid emanating from blood vessels is similar in composition to blood serum. Dictionary foreign words, included in the Russian language. Chudinov A.N., 1910. TRANSUDATE - protrusion of the liquid part of the blood (transudate) from the blood... ... Dictionary of foreign words of the Russian language Big Encyclopedic Dictionary

Edema fluid accumulating in cavities and tissues as a result of impaired vascular permeability. It differs from exudate in lower protein content, poorer cellular composition, and the absence of microbes. See Ascitic fluid. (

The study of fluids obtained through a test puncture of the chest and abdominal cavities, joints, abscesses and cysts aims to study the properties of the extracted punctate. The data from this type of research are significant diagnostic value, in many cases decisive in determining the nature of the disease process that caused the accumulation of fluid. The amount of extracted punctate is not significant. It is important only in prognostic terms. While in some cases it is barely possible to collect only a few cubic centimeters of effusion, in others it can be removed in liters. The question of the origin of punctate and the nature of the disease in each special case essentially decided on the basis of fluid testing data.

By means of a test puncture of the chest and abdominal cavities, various types of exudates, transudates, blood, stomach or intestinal contents, urine, and the contents of various types of cysts and echinococcal blisters can be obtained.

The study of punctates aims to determine physical properties liquid, its chemical composition, the study of formed elements mixed with effusion, and, finally, bacteriological research.

When determining the physical properties, pay attention to the color of the effusion, its transparency, consistency, specific gravity and reaction.

By appearance, effusions are distinguished: a) completely colorless, b) painted in one color or another, c) transparent, d) opalescent, e) cloudy and f) milky white.

Completely colorless and transparent, as clear as water, is the content of echinococcus blisters and saccular tumors - cysts; transparent also includes transudates and serous exudates, as well as urine that accumulates in the abdominal cavity during rupture Bladder. The color of the effusion and the intensity of its color may vary.

Serous exudates and transudates are almost completely transparent, only slightly opalescent liquids of a beautiful lemon-yellow color. The admixture of a small amount of blood dye gives them a reddish tint; with more severe extravasation, the liquid becomes red and even cherry-red, not differing significantly in color from blood.

Turbid liquids include gray-fibrinous, purulent and ichorous exudates, hemorrhagic exudates that accumulate in tuberculous lesions of the serous membranes, as well as in malignant neoplasms of the thoracic and abdominal organs, the contents of the stomach and intestines, and, finally, hemorrhagic transudates that accumulate in the abdominal cavity during thromboembolic colic and some forms of ileus.

Milky-white exudates are chylous, chyle-like and pseudochylous.

The milky-white color of chylous exudate, which accumulates in the abdominal cavity when the lymphatic vessels of the cavity rupture, is caused by the admixture of a large amount of fat, which, when settled, accumulates in the form of a thick creamy mass on its surface. After adding a few cubic centimeters of ether, alkalized with a drop of caustic potassium, the liquid, due to the complete dissolution of fat, becomes completely transparent. In the preparations processed by Sudan 111, microscopic examination reveals a mass of intensely red colored fat grains. With chronic inflammation of the serous membranes, for example, tuberculosis, chyle-like exudates accumulate in the cavities, the characteristic color of which depends on the accumulation of a large number of decayed fatty degenerated cells. This kind of exudates contains much less fat; after adding ether, the liquid, only slightly cleared, remains cloudy due to the admixture of a large number of endothelial cells and leukocytes suspended in it.

Pseudochyleous exudates, which resemble diluted milk in color, contain only a very small amount of fat. They do not clear up after adding ether and do not form a creamy layer when settling. Some explain their characteristic coloring by the presence of lecithin-containing globulins, others - by nucleids and mucoids.

In terms of their consistency, effusions obtained by puncture are most often completely liquid; this includes exudates, transudates, fluid from the echinococcal bladder, urine, etc.; Only the contents of uterine cysts have a clear mucous consistency. Due to the admixture of large amounts of pseudomucin, punctates of ovarian cysts show a clear mucous consistency and can stretch into long thin threads. The contents of the uterus that fall into the uterus when it ruptures abdominal cavity, is a thick, viscous mass that also stretches into long threads. Microscopic examination reveals many leukocytes and epithelial cells in the sediment.

When determining Specific Gravity The punctuation is usually used Breakdown Detre, Which is only a modification of the Hammerschlag sample. Determination using a hydrometer is not always possible due to the rapid coagulation of the liquid; in addition, it requires a large amount (up to 25 cubic cm) of punctate. To delay coagulation, it is recommended to collect the punctate in a vessel immersed in water heated to 38°. The study should be carried out with hydrometers set to a temperature of 36°.

The Detre method is based on the difference in specific gravity of the main solution and the test liquid. If you drop a drop of effusion into a liquid of a lighter specific gravity, it quickly sinks to the bottom; in a heavier solution, the drop floats on the surface. If the specific gravity is identical, it turns out to be suspended in the solution, floating in it, without rising or falling.

4 solutions are used as the main ones table salt specific gravity 1.010 (1.380%), 1.020 (2.76%), 1.030 (4.14%) and 1.040 (5.52%). Basic solutions are prepared using distilled water, adding the indicated amounts of table salt. The specific gravity of the reagent must be verified accurately using a hydrometer. First, the concentration of boundary solutions is determined. For this purpose, one drop of the test liquid is dropped using a pipette into basic solutions poured into test tubes. If in a solution with a specific gravity of 1.020 a drop sinks to the bottom, and with a specific gravity of 1.030 floats on the surface, the specific gravity of the liquid under study lies somewhere in the range of 1.020-1.030. Having then prepared intermediate concentrations by appropriately diluting a solution with a specific gravity of 1.030 with distilled water (9 + .1.8 + + 2.7 + 3, etc.), the final determination is made.

The specific gravity of the transudate ranges from 1.005 to 1.018. The highest specific gravity is found in lunctates with pneumothorax, when the liquid in its properties is between transudates and exudates.

Exudates are more dense. Their specific gravity is usually higher than 1.018. However, the differences in this regard between exudates and transudates are not always constant. In many cases, the specific gravity of the exudate is below the limit; on the other hand, transudates with a very high specific gravity are often encountered.

The punctate reaction has great importance when examining the contents of the stomach and bladder. Effusions from dropsy and inflammation of the serous membranes usually have an alkaline reaction. The observed fluctuations in the concentration of hydrogen ions are very unstable and do not have significant significance in differentiating transudates from exudates. Stomach contents sharply acid reaction with a sour odor and often contains blood; urine when the bladder ruptures in carnivores is most often neutral, sometimes acidic, and less often noticeably alkaline.

Determination of the amount of protein is the main point in the study of effusion, since quite significant differences have been established in this regard, helping to differentiate exudates from transudates. The most accurate results are obtained by weighing the dry protein sediment. For precipitation, use a 1% solution of table salt acidified with a drop of acetic acid. K 100 cu. cm of hot NaCl solution add 10 cubic meters. cm of the test liquid and filter after thorough shaking; the precipitate is washed with water, acidified with acetic acid, alcohol, ether, dried in a desiccator and weighed. By subtracting the weight of the filter from the total weight and multiplying the resulting difference by 10, the percentage of protein in the liquid is obtained.

Of the simpler methods, the Roberts-Stolnikov method gives fairly accurate results (see determination of protein in urine). Since the specific gravity of punctate depends mainly on the amount of protein dissolved in it, its content in the liquid can be approximately calculated from the specific gravity using the formula: x = aD (UD - weight - 1,000) - 2.88 for exudates Px = g1ya(UD - weight - 1,000) -2.72 for transudates.

The simplest and most convenient method, which allows one to determine not only the total amount of protein, but also to establish the relationship between protein fractions, is the refractometric method.

The protein content in transudates, compared to exudates, is not particularly high and is usually below 2.5%. Only in rare cases, such as with ascites, dropsy, due to pneumothorax, its amount in transudates reaches 3 and even 4%. The protein content in exudates is significantly higher than 2.5% and often reaches 4 and even 5%. This kind of relationship helps to easily differentiate inflammatory effusions from mechanical ones. However, cases are often observed when the protein content in the exudate is slightly lower than the specified limit. Significant services in assessing this kind of effusion in such cases are provided by the Rivalt reaction, as well as the Moritz reaction.

The Rivalt reaction is based on the precipitation of a special protein precipitated by dilute acetic acid. This type of protein substance can only be detected in inflammatory effusions. Transudates do not contain it at all. Weak solutions of acetic acid are used as a reagent (2 drops per 100 cubic cm of distilled water). The technique is extremely simple. In a narrow cylinder with a capacity of 25 cubic meters. cm pour 20 cubic meters. see reagent. Then, using a pipette, one drop of the test liquid is applied to its surface. In the presence of protein, a drop falling slowly leaves a cloud of turbidity, and a small cloudy sediment forms at the bottom. Transudates quickly dissolve in the reagent without causing cloudiness.

Moritz's reaction. K 2-3 cu. cm of punctate add a few drops of 5% acetic acid. Exudate gives turbidity and sediment, transudate gives slight turbidity.

Based on the results of these tests, in cases where there is no sharp difference in specific gravity and protein content, it is possible to accurately differentiate exudate from transudate.

Determination of pseudomucin. The contents of ovarian cysts, which are a yellowish or dirty-brown viscous liquid with a specific gravity of 1.005 to 1.050, are distinguished by the presence of a peculiar protein body, α-pseudomucin. Pseudomucin is not precipitated by either acetic or nitric acid, but precipitates under the influence of alcohol. However, this difference is not conclusive, since serum proteins, a constant component of effusions, are also precipitated by alcohol.

To determine pseudomucin, 25 cc. cm of punctate, add a few drops of an alcoholic solution of rosolic acid, heat it to a boil and then add drops of 1/10 sulfuric acid solution until a slightly acidic reaction. The slightly yellowed liquid after this treatment is brought to a boil again and then filtered. Full transparency filtrate indicates the absence of pseudomucin.

Particularly important in determining the nature of the effusion and its origin is the microscopic examination of the sediment - Cytoscopy. The study of the morphological elements of effusion not only makes it possible to distinguish exudates from transudates, but at the same time sometimes allows us to draw conclusions regarding the etiology of the disease, accompanied by the accumulation of effusion in body cavities.

For microscopic examination, use the sediment obtained by centrifugation. To remove fibrin clots, which significantly complicate the study, it is better to defibrate the liquid. For this purpose, the effusion is placed in a thick-walled bottle with glass beads and shaken for 30-60 minutes. The liquid defibrated in this way is poured into conical tubes and centrifuged until a test drop taken from the surface no longer contains formed elements. After draining the clear liquid, the sediment is carefully stirred using a glass rod. The resulting emulsion is used to prepare smears and fresh preparations.

Staining of fresh preparations is most often done 1% aqueous solution methylene blue, one drop of which is mixed with a drop of the taken emulsion. After carefully stirring the mixture with a glass rod, cover it with a cover glass, remove excess liquid that has protruded beyond the edge of the glass with filter paper, and immediately examine it. Under a microscope, it is easy to distinguish large, loose endothelial cells, compact ones with a characteristic nucleus, white blood cells, anucleate erythrocytes, cells of various neoplasms and a variety of microbial flora.

Fresh preparations are prepared only for ex tempore research; They quickly deteriorate; they can only be preserved with the help of a special kind of preservative composition.

Much more convenient in this regard are dry preparations, which are prepared by smearing a drop of emulsion on the surface of a glass slide.

After drying, the smear is fixed with methyl alcohol and stained with Giemsa.

When assessing the results obtained, it should be remembered that the reaction of the serous membranes to mechanical irritations (transudates) is expressed by abundant desquamation of the endothelium; Serous membranes respond to pyogenic infections with neutrophilia, while tuberculosis is characterized by lymphocytosis.

In effusions from heart and kidney diseases, therefore, a huge number of large endothelial cells are found, grouped in groups of 5-10 cells. These clusters are sometimes so abundant that they completely cover the entire field of view. They are easily distinguished from leukocytes by their large, highly vacuolated nucleus, which stains purple, and delicate pink protoplasm surrounding the core in a thick layer. In addition to endothelial cells, a large number of erythrocytes, lymphocytes and individual neutrophils are found in transudates.

At serous pleurisy and peritonitis caused by the action of pyogenic microbes, an accumulation of a large number of segmented and band neutrophils, as well as erythrocytes, is found in the exudates. Endothelial cells and lymphocytes are poorly represented.

In tuberculous pleurisy, the field of view is covered with a mass of small lymphocytes, among which there are individual cells of medium and large size. Sometimes to them large quantities red blood cells are mixed in. Neutrophils and eosinophils are poorly represented. According to Vidal, their number should not exceed 10% of the total mass of leukocytes.

In malignant neoplasms, huge cells are found with highly vacuolated, often degenerated protoplasm and a large kidney-shaped or oval nucleus, in which several (2-3) nucleoli can be seen. These types of cells are considered specific for malignant neoplasms.

Tumor immunology. Immune aspects of autoimmune pathology

Therapeutic physical training for respiratory diseases

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