AB0749 LABORATORY MARKERS OF INFLAMMATORY ACTIVITY IN PATIENTS WITH MONOGENIC AND POLYGENIC AUTOINFLAMMATORY DISEASES
Authors: E. Fedorov, S. Salugina, M. Cherkasova, A. Gerasimenko, M. Kaleda
Journal: Annals of the Rheumatic Diseases (2021)

Background: Auto-inflammatory diseases (AIDs) – a group of diseases of monogenic and polygenic nature, manifested by recurrent attacks of systemic inflammation in the form of fever, accompanied by multi-system symptoms, which are based on the pathology of natural immunity in the absence of autoantibodies and markers of infection. Objectives: to evaluate the serum levels of markers of systemic inflammation in patients(pts) with monogenic AIDs (FMF, CAPS, TRAPS) and polygenic AID-systemic Juvenile Arthritis (sJA). Methods: In 85 pts (68 children and 17 adults) with monogenic AIDs and sJA, the concentrations of C-reactive protein (CRP), serum amyloid A(SAA) and ferritin in the blood serum were detected. SRP and SAA were determined by the nephelometric method using Siemens reagents on a BN Prospect Siemens analyzer. Normal CRP values are 0-5 mg/L, normal SAA values are 0-5 mg/L. Ferritin was determined by ELISA using kits manufactured by Orgentec Diagnostica GmbH(normal values of 7-142 μg/l). During statistical processing of the material, the median(Me), lower and upper quartiles(LQ and UQ), minimum and maximum values were evaluated, and the reliability of differences between the groups was evaluated using the Mann-Whitney U criterion. The correlation between the values of CRP and SAA, CRP and ferritin was estimated by the Pearson criterion. Results: The study included 30 with systemic JIA, FMF-17 pts, CAPS 25- pts and TRAPS- 17 pts. The results of the detection of CRP, SAA, and ferritin are presented in Table 1. Table 1. CRP, SAA, and ferritin values in patients with sJA, FMF, CAPS and TRAPS. Value sJA FMF CAPS TRAPS CRP (N=0-5 mg/L) Me (LQ - UQ) 6,95(0,5- 51,7) 30,8(9,41-47,4) 4,61(0,36-20,4) 5,41(2,77-14,7) Min 0,15 0,48 0,15 0,15 Max 229,0 109,0 80,3 90,1 SAA(N=0-5 mg/L) Me (LQ - UQ) 19,05(3,05-257,0) 85,2(38,4-276,0) 7,83(2,25-122,0) 10,6(5,7-72,7) Min 0,88 1,58 0,88 0,88 Max 962,0 923,0 346,0 516,0 Ferritin (N=7-142 μg/l) Me (LQ - UQ) 61,09(22,03-385,76) 57,22(21,36-133,51) 20,49(8,13-28,88) 16,52(5,42-67,27) Min 0,73 3,36 0,98 2,42 Max 1500,0 174,22 183,57 930,1 Serum concentrations of CRP that exceeded the reference values were observed in 15(50%) pts with sJA, 11(65%) pts with FMF, 17(65%) pts with CAPS, and 5 (29%) pts with TRAPS. An increase in SAA was observed in 23(77%) pts with sJA, 12(71%) pts with FMF, 17(68%) pts with CAPS, and 8 (47%) pts with TRAPS. An increase in ferritin was observed in 9(30%) pts with sJA, 1(6%) pts with FMF, 1(4%) pts with CAPS, and 1 (6%) pts with TRAPS. A statistically significant difference in the Mann-Whitney U test for SAA concentration was found only between the CAPS and FMF groups (P=0.03), and in the CRP concentration also only between the CAPS and FMF groups(P=0.009). The strongest statistically significant correlation according to the Pearson criterion in the whole study group was noted for CRP and SAA: r= 0.74(p=0.0000), which corresponds to the average correlation strength, a slightly weaker correlation was noted for the pair of CRP/ferritin values: r=0.53 (p=0.0000), which also corresponds to the average correlation strength. For the SAA/ferritin pair as a whole, the lowest correlation was observed in the studied group: r=0.36(p=0.0008). The maximum correlation of studied parameters was observed in the group of patients with TRAPS: for the CRP/SAA pair, it was r= 0.9(p=0.00003), for the SAA/ferritin pair it was r= 0.7(p=0.0072), and for the CRP/ferritin pair, r= 0.59(p=0.0345). For FMF, there was a strong correlation in the SRP/SAA pair r=0.89(p=0.0000). Conclusion: In the study group, all AIDs, both monogenic(FMF, TRAPS, CAPS) and sJA, were characterized by an increase in the levels of CRP and SAA, but to the greatest extent these indicators were increased in sJA and FMF, and to the least in CAPS. CRP and SAA correlate well with each other, especially with TRAPS and FMF. The maximum values of ferritin and the highest frequency of its increase were noted in the sJA group. Ferritin in the majority of pts with monogenic AIDs were normal. Disclosure of Interests: None declared