SUN-413 C3 GLOMERULOPATHY: 2 YEARS’ EXPERIENCE, NEPHROLOGY DEPARTEMENT MONASTIR

Abstract

C3 glomerulopathies (C3 G) are rare diseases that share an underlying mechanism of complement dysregulation. Diagnosis relies solely on renal biopsy immunofluorescence findings characterized by glomerular deposits of C3 with minimal or no immunoglobulin (Ig) deposits; light microscopy findings and complement biomarker profiles are heterogeneous, We present in this study our experience about 6 cases of C3 G diagnosed at the nephrology department from Janury 2017 to october 2019 This is a retrospective, descriptive study. We included a group of 6 medical records of patients with C3G with a performed native renal biopsy. In all cases light microscopic and immunofluorescence evaluation were performed. The median age at diagnosis was 58 years,( minimum age 36 years and maximum 66 years), with a female predominance (4 women Vs 2 men ), three patients had a history of high blood pressure, a case of diabetes mellitus, hypothyroidism and the youngest woman had recurrent angina, no history of infection, positive autoimmune findings, or monoclonal gammopathy was identified. Initial presentation was as follow: oedema in three cases, inflammatory polyarthraligia in 2 cases, and only one patient presented oligoanuria. the majority presented sediment anomaly (non-nephrotic Pu + Hu) with renal insufficiency with median Glomerular Filtration Rate(GFR) and proteinuria of 30ml/min/1,73m² and 2,5 /24h, respectively and only one patient had a nephrotic syndrome (defined by a Pu> 3 g / 24h, hypolabuminemia <35 g ), hematuria was always present except one case, a biological inflammatory syndrome was present in all cases, only one had unexplained biological cholestasis, both men had leg purpuric lesions, C3/C4 levels were low in 4 cases however CH50 was low in one, exploration of the alternative complement pathway is in progress (Factor, H and I). The etiological assessment of a MPGN included: a myelogram, cardiac ultrasonography, serology of hepatitis B and C, was negative. Membranoproliferative and mesangial proliferative glomerulonephritis were the common patterns of injury nevertheless one patient had Crescentics. The treatment was as follow 0.5 mg / kg / day of corticosteroid therapy with Mycophenolate mofetil in 5 cases, 4 had a good evolution with a decreased proteinuria and hematuria level and DFG stabilization, in one case the outcome was good with only corticosteroid, this patient presented nephrotic syndrome without renal insufficiency and 1 patient progressed to ESRD. Because clinical courses and prognoses among glomerular diseases with dominant C3 deposition differ, further understanding the background mechanism, particularly complement dysregulation in C3G, is needed. This may resolve current dilemmas in practice and shed light on novel targeted therapies to remedy the dysregulated alternative complement pathway in C3G.