METHOD FOR DIFFERENTIAL DETERMINATION OF PROBABILITY OF PRESENCE OF INFLAMMATORY BOWEL DISEASES Russian patent published in 2024 - IPC G01N33/49 G01N33/68 G01N33/72 G01N33/92 G01N33/573 G01N1/28 

FIELD: medicine; gastroenterology.

SUBSTANCE: invention can be used for differential determination of probability of presence of inflammatory bowel diseases by examining the level of fecal calprotectin, red blood values, biochemical parameters, levels of fatty acids of blood serum and erythrocyte membranes. Faecal sample is taken from the patient and the level of fecal calprotectin is determined by enzyme immunoassay; venous lean blood is simultaneously taken in three test tubes: first test tube with anticoagulant—potassium salt of ethylenediaminetetraacetate (EDTA), from the blood of which using an automatic hematological analyzer, the hemoglobin level, hematocrit, the average corpuscular volume of the erythrocyte (MCV) are determined, average content of hemoglobin in 1 erythrocyte (MCH), average concentration of hemoglobin in erythrocytes (MCHC), erythrocyte sedimentation rate. Second test tube with a coagulation activator and gel, from which blood serum is obtained, which is immediately separated from the clot, is placed in two dry clean test tubes. Further, in the blood serum of the first test tube, C-reactive protein, ferritin, samples are obtained from the blood serum of the second test tube for determining the levels of fatty acids—arachidonic, total polyunsaturated fatty acids, ratio of omega 6 to omega 3 polyunsaturated fatty acids by gas chromatography and mass spectrometry. Third tube with sodium citrate, from which blood plasma is obtained, which is immediately separated from suspension of erythrocytes, then in blood plasma fibrinogen concentration is determined by Clotting method, erythrocyte suspension is subjected to three-fold washing with phosphate buffer to obtain washed erythrocytes, from which samples of erythrocyte membranes are obtained for determining levels of oleic, arachidonic, total polyunsaturated fatty acids by gas chromatography and mass spectrometry, then two diagnostic indices Y_D1 and Y_D2 are calculated by original formulas. If the diagnostic index Y_D1 exceeds 0.66, the probability of inflammatory bowel disease is determined. If Y_D1 exceeds 0.66, then Y_D2 is calculated. If the diagnostic index Y_D2 exceeds 0.5, the probability of ulcerative colitis is determined. If the value of the diagnostic index Y_D2 is less than 0.5, the probability of the presence of Crohn's disease is stated.

EFFECT: method provides the possibility of increasing the specificity and accuracy of verifying the diagnosis of inflammatory bowel diseases at earlier stages with determination of its variants by taking into account of red blood values, levels of serum and faecal markers of inflammation, levels of fatty acids of erythrocyte membranes and blood serum.

1 cl, 3 dwg, 6 tbl, 3 ex