COAGULATIVE TESTS

From Big Medical Encyclopedia

COAGULATIVE TESTS (synonym: sedimentary tests, flokkulyatsionny tests, disproteinemichesky tests, tests on lability of serum proteins) — the colloid reactions intended for detection of quantitative and qualitative changes of serum proteins of the person at various patol, states. K K. items belong tests from group of reactions of Takat (Takat's test, Gross's test, Veykhbrodt's reaction, sublimate test), a thymol turbidity test, cadmic test (a synonym Vurmanna — Vunderli reaction ), at a cut as the factor breaking colloid stability of blood serum sulfate cadmium, formolovy test, zinc - sulfate test (Kunkel's reaction), kephalin - cholesteric test, Veltmann's reaction and zolotokolloidalny test use.

At patol, processes serum proteins change quantitatively and qualitatively. Increase in amount of globulins or their separate dispersive subfractions, reduction of amount of albumine, emergence of proteins, unusual to norm, lead to disturbance of colloid stability of serum proteins and to them coagulations (see) under the influence of factors which at usual conditions do not cause sedimentation of proteins. The mechanism of this coagulation is finally not found out.

To. items considered before only funkts, tests of a liver therefore they in clinic were called «hepatic tests». However further it was established that To. items have diagnostic value at all diseases which are followed by a disproteinemia (see. Proteinemia ). Results To. the item should be regarded in combination with results of other researches, both laboratory, and clinical. Only in that case To. items matter for diagnosis of diseases of a liver.

Results To. items are expressed in conventional units of a turbidity or in number of milliliters of the reactant added to blood serum before emergence of permanent opacification.

Use To. the item in a lab. to diagnosis it was reduced, they are replaced more specific, exact and informative a lab. tests (electrophoresis and Immunoelectrophoresis of serum proteins, enzimologichesky tests, etc.). Nevertheless thanks to simplicity of performance To. items are still applied rather widely. In our country the greatest distribution of a polumila timolovy, sublimate tests and Veltmann's test (see. Veltmanna coagulative test ).

Thymol turbidity test (test of timolovy opacification, a timolovy turbidity) it is based on definition of extent of opacification of blood serum after addition of saturated solution of methyl-isopropyl phenol in the veronalovy buffer. Test is offered in 1944 by N. F. Maclagan. The chemical essence of a thymol turbidity test is not found out; perhaps, emergence of a turbidity is explained by formation of a globulinotimolofosfolipidny complex.

Most of researchers consider that test is positive at reduction of fraction of albumine and increase in fractions beta and gamma-globulins and lipoproteids. Intensity of opacification depends on composition of buffer solution, the size pH, concentration and degree of purity of methyl-isopropyl phenol and on temperature. Extent of opacification is estimated by Maklagan's units (unit. L) based on the standards offered F. Kingsburry in 1926 for definition of protein in urine. R. Shank and Hoglend (S. of Hoagland) in 1946 suggested to apply the bariyevosulfatny standard to assessment of a thymol turbidity test, and to take measurement of a turbidity on the spectrophotometer. The results received at such measurement are close to the results received by Maklagan's method.

As the unified method in our country modification At an erg (J. Huerga) and Popper is accepted (N. of Popper) — so-called timoloveronalovy test, at a cut degree of a turbidity is determined by a fotokolorimetrirovaniye at 660 nanometers against the timoloveronalovy buffer; calculation is conducted according to a standard curve.

Normal the turbidity of blood serum after conducting timoloveronalovy test is equal to 0 — 4 units of M. Increase in a turbidity (positive test) demonstrates defeat of a parenchyma of a liver at epidemic or serumal hepatitis, and test is positive even before development of jaundice, at anicteric hepatitises, at cirrhoses of a liver, after the postponed hepatitis etc.

Sublimate test (sulemovo-sedimentary reaction) treats group of reactions of Takat. The reaction of Tokat which was originally called Takat's reaction — the Macaw, was offered Takata (M. to Takata) and Ara (K. Aga) in 1925. This reaction is that at interaction of corrosive sublimate and sodium carbonate with blood serum in the last flakes appear. The mechanism of reaction is completely not found out. The modification of reaction of Takat offered by Grinstedt was widely adopted (T. Grinstedt) in 1948 and known as Grinstedta reaction. She also received the name of sublimate or sulemovo-sedimentary test. Sublimate test differs in simplicity of performance and good reproducibility. Results of sublimate test are expressed in milliliters of 0,1% of the solution of corrosive sublimate added to 0,5 ml not of gemolizirovanny blood serum, divorced 1 ml fiziol, solution before emergence of permanent opacification when through a vertical slice of liquid there is impossible a reading of the newspaper text. The norm is equal to 1,6 — 2,2 ml of 0,1% of solution of corrosive sublimate. Test is positive at parenchymatous damages of a liver, especially at cirrhosis, acute and hron, toksiko-chemical damages of a liver, a silicosis, a tuberculosilicosis.



Bibliography Todorov Y. Clinical laboratory trials in pediatrics, the lane with bolg., page 707, Sofia, 1968; Hazanov A. I. Functional trials in diagnosis of diseases of a liver, page 41, M., 1968; Clinical chemistry, ed by R. J. Henry a. o., Hagerstown, 1974.

S. P. Mikhaylova.

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