RU1802870C - Method of hyperuricemia detection - Google Patents

Abstract

Usage: medicine, clinical biochemistry. Summary of the invention: a reagent consisting of 3,5-dichloro-2-hydroxylbenzenesulfonic acid, urinase, peroxidase and 4-aminoantipyrine is added to the tear fluid, the mixture is incubated for 5 minutes at a temperature of 37 ° C and the level is determined uric acid by spectrophotometry at 520 im and with a value of this indicator above 120 mmol / l indicates the presence of hyperuricemia. Positive effect: the method is atraumatic, the use of the method allows determining the presence of hyperuricemia within 15 minutes.

Description

The invention relates to medicine, namely to clinical biochemistry and can be used to detect hyperuricemia in gout and chronic nephritis.

The aim of the invention is to accelerate and reduce the invasiveness of the method.

This goal is achieved by the fact that the diagnosis of hyperuricemia is carried out by determining uric acid in a patient’s tear, and with a uric acid value in the tear of more than 120 µmol / L, the presence of hyperuricemia is judged.

The proposed method takes no more than 15 minutes in time: 2 minutes to take a tear, 10 minutes to carry out the reaction (pouring reagents 5 minutes, temperature control 5 minutes), 3 minutes to record the readings of the device.

The method is carried out as follows.

A drop of tears (0.03 ml) is taken from a patient with an eye dropper after holding a fleece moistened with 10% ammonia in the nose. A specific, enzymatic method was used to determine uric acid. It is based on the breakdown of uric acid by uricase to allantoin, carbon dioxide, hydrogen peroxide, followed by an indicator reaction. Under the action of peroxidase, chromogen, hydrochloric acid and water are formed from peroxide with amino-4-antipyrine and 3,5-dichloro-2-hydroxybenzenesulfonic acid.

Experimental test. To 0.02 ml of tear add 1 ml of working solution. Mix, incubate for 5 min at 37 ° C in a thermostat. Measure the extinction in a cuvette on a spectrophotometer at a wavelength of 520 nm against a blank sample. Stain stable for 30 minutes. The working solution is prepared as follows.

about y

00

3

00

som: to 25 ml of 150 mmol / L phosphate buffer, pH 7 with 3,5-dichloro-2-hydroxybenzenesulfonic acid (2 mmol / L), uricase (100 units / L), peroxidase (5; 200; u / l), 4-aminoantipyrine (0.25 mmol / l).

A blank sample is also treated as an experimental one, but instead of a tear, 0.02 ml of physiological saline is taken.

The calibration sample is treated as an experimental one, but instead of a tear, they take 0.02 ml of a standard (476 mmol / l) uric acid solution. Measured under the same conditions against a blank sample.

Eop

The calculation was carried out according to the formula: A

n where

A is the amount of uric acid, µmol / l; EOP extinction experimental test; Ek is the extinction of the calibration sample; p 476 μmol / L.

It has been established that 62.9 + 5.5 µmol / L uric acid is contained in a tear of a healthy person. The oscillations in individuals were from 28 to 90 μmol / L.

In the blood serum of healthy people, the uric acid content is 351.5 + 10.9 μmol / L. Oscillations in individuals from 245 to 418 μmol / L. The average tear / blood ratio is 0.18.

In patients with hyperuricemia (with gout, kidney disease), 191.6 + 22.3 µmol / L uric acid is contained in the tear. The maximum uric acid content in the examined patients was 305 m µmol / L, at least 121 µmol / L.

In the blood serum of patients with hyperuricemia, the uric acid content is 663.0 + 47.8 μmol / L. The maximum serum is 884, the minimum is 514 μmol / L uric acid. The average tear / blood ratio in patients is 0.29. In statistical processing, the difference between the uric acid content in the tear of healthy people and patients with hyperuricemia is highly significant (P 0.001).

With an increase in uric acid in a tear above 120 μmol / L, hyperuricemia was diagnosed. ..

The data are confirmed by clinical and laboratory tests on 16 healthy people, 5 patients with gout and 16 patients with chronic nephritis on the basis of the nephrology and cardiology departments of MSCh No. 9 of Perm from June 23, 1989 to July 24, 1990.

PRI me R 1. Healthy man U. 42. Year ....

Tear Analysis from December 19, 1989

Uric acid 69 μmol / L.

A blood test from December 19, 1989. Urine acid is 324 μmol / L. The subject has a normal uric acid content in the tear and blood. PRI me R 2. Patient T., 46 years old.

He entered the nephrology department with complaints of pain in the lumbar gland, headache, pain in the area of the first metatarsophalangeal joint. Diagnosis at admission: urolithiasis, symptomatic hypertension. The patient's condition is satisfactory, the skin is pale. The boundaries of the heart are within normal limits, heart sounds are rhythmic. Blood pressure 170/100. Vesicular respiration. The abdomen is soft, painless. The kidneys are not palpable. Pasternatsky’s symptom is positive on both sides.

From a biochemical blood test: urea 9.5 μmol / L, uric acid 784 μmol / L.

Tear analysis: uric acid 236 μmol / L, indicating hyperuricemia,

Urinalysis: straw yellow. turbid, acidic reaction. Specific gravity 1012; protein 0.33 g / l; white blood cells 20-25; 2-3 hyaline cylinders; granular 2-4; epithelial cells 7-8. Urata-n-f. Thus, the patient has an increase in the blood content of uric acid, urea, in a tear, the content of uric acid is increased.

Final diagnosis: Urolithiasis, symptomatic hypertension. Gouty arthritis of the first metatarsophalangeal joint.

Example 3. Sick L „27 years. She was admitted to the nephrology department with complaints of headache, weakness, and fatigue. The condition is satisfactory, the skin is pale, dry. The face is pasty. Heart sounds are rhythmic, blood pressure is 150/90. The vesicular breathing, the abdomen is soft, painless.

General blood test: red blood cells 3.1 -10 / l; hemoglobin 102 g / l; color indicator 1; white blood cells 6.0 10 ° / l; CO2 33 ml / h.

From a biochemical blood test: protein 79.4 g / l; urea 25.7 mmol / l; creatinine 0.47 mmol / L; uric acid 514 μmol / l ..

Urinalysis: urine is cloudy, acid reaction. Protein 3.3 g / l; epithelial cells 5-7; white blood cells 8-10; red blood cells 20-30. Analysis of tears from September 26, 1989. Uric acid 181 μmol / L.

Thus, in a patient with anemia, the content of urea, creatinine, uric acid in the blood is increased, the content of uric acid in the tear is increased.

The final diagnosis: chronic glomerulonephritis, hypertension, exacerbation. Chronic renal failure of 2-3 degrees.

The content of uric acid in a tear is increased in patients only in the presence of hyperuricemia. With an increase in uric acid in a tear above 120 μmol / L, we diagnose hyperuricemia.

The proposed method for the diagnosis of hyperuricemia is much faster and simpler than the known method, easily tolerated by patients, and atraumatic. Of particular value when used in dynamic

5

Claims (1)

ke disease. The method is simple, reliable and available for use in a number of clinical biochemical laboratories. SUMMARY OF THE INVENTION A method for detecting hyperuricemia, comprising determining the level of uric acid in a biological fluid by adding to the sample a reagent consisting of 3,5-dichloro-2-hydroxybenzenesulfonic acid, uricase, peroxidase and 4-amino antipyrine, incubating the mixture for 5 minutes at 37 ° C followed by spectrophotometry at 520 nm, characterized in that, in order to accelerate and reduce the invasiveness of the method, the level of uric acid is determined in the tear fluid and, with a value of this indicator above 120 mmol / l, the presence of g iperuricemia.