Концентрация сывороточного белка-предшественника амилоида в крови у больных ювенильным ревматоидным артритом, имеющих протеинурию

AIM OF RESEARCH. To estimate concentrations of serum amyloid precursor protein (serum amyloid A protein – SAA) in blood of children with juvenile rheumatoid arthritis (JRA), to compare SAA concentration with pathology of urine analyses. PATIENTS AND METHODS. 60 children with JRA were examined. Сoncentration SAA in blood of patients was measured by an enzyme linked immunoelectrodiffusion essay. Dynamics of clinical urine analyses, daily proteinuria, total protein value, serum albumin value, glomerular filtration rate (GFR) were estimated by endogenous creatinine clearance. RESULTS. 31 of 60 patients (51,7%) had normal urine analyses. 29 patients (48,3%) had proteinuria, 28 from them had daily proteinuria value less than 1g/m2/24h. One patient with rheumatoid renal amyloidosis because of long-standing systemic JRA had proteinuria up to 33g/m2/24h, GFR - 40 ml/min, maximal SAA concentration 828 mg/l. 59 of 60 patients with JRA had normal GFR according to endogenous creatinine clearance. Increased blood SAA concentration (292,3±30,9 mg/l) was revealed in 56 of 60 children (93,3%). In 31 patients with JRA without proteinuria in 28 (90,3%) was observed increased SAA concentration (205,7±44,3 mg/l). In 28 of 29 patients with proteinuria (96,6%) was determined increased blood SAA concentration (378,8±36,7 mg/l). SAA concentration in 28 patients with proteinuria (378,8±36,7 mg/l) was authentically higher than SAA (205,7±44,3 mg/l) in blood of 28 patients without proteinuria. CONCLUSION. In 93,3% patients with JRA increased blood SAA concentration was determined. The results revealed that blood SAA concentration in patients with JRA and proteinuria was higher than in patients without proteinuria.