MON-021 IMMUNOHISTOLOGICAL SPECTRUM OF CRESCENTIC GLOMERLONEPHRITIS, A SINGLE CENTER STUDY IN BANGLADESH

Abstract

Crescentic glomerulonephritis (GN) is defined as presence of crescents in >50% of glomeruli sampled for renal biopsy. This is a critical diagnosis with clinical implications that ideally is communicated to the referring physician immediately. There is limited data on the etiology, clinical and histopathological spectrum of crescentic glomerulonephritis (CrGN) in Bangladeshi population. All the crescentic glomerulonephritis diagnosed histologically at Armed Forces Institute of Pathology, Dhaka irrespective of age and sex are included in the study. The study duration was from January 2017 to June 2018. The renal biopsy samples were undergone H&E, PAS, Masson trichrome and Methanamine silver staining. For each case direct immunofluoresnece study was carried out for IgG, IgM, IgA, C3, C1q, Kappa and Lambda. Depending on clinical, biochemical, serological, histological and immunofluorescence evaluation crescentic glomerulonephritis was classified. During stipulated period 21 crescentic glomerulonephritis were diagnosed which comprises 2.56% out of total 819 non transplant renal core biopsy patients. Mean age was 27.238 +14.928 the largest age group (8/21) being paediatric age group (<16 yrs). The male female ratio was 0.75. The most common presentation was rapidly progressive glomerulonephritis (RPGN) (7/21), followed by generalized body swelling (6/21). On urine examination 19/21 patients had haematuria and 7/21 patients had massive proteinuria (>3.0 Gm/24 hrs). The mean serum creatinine level was 5.65 mg/dl (1.3 to 18.85 mg/dl). Serum C3 & C4 level was found low in 6/18 and 2/15 cases respectively. ANA was positive in 2/21 cases and among those 1 was anti dsDNA positive and labeled as systemic lupus erythematosus (SLE). Among 21 cases 01 could not be classified due to lack of glomerulus during direct immunofluorescence (DIF) study. Pauciimmune crescentic glomerulonephritis (PI-CGN) was 10 (50%), Immune complex mediated crescentic glomerulonephritis (IC-CGN) was 9 (45%) and anti glomerular basement membrane disease (anti GBM disease) was 01(5%). Among the PI-CGN, 5 (50%) were ANCA positive and 03 (30%) were ANCA negative, for other 02 PI-CGN cases ANCA report was not available. Among ANCA positive PI-CGN 01 had associated ANA positivity. Among IC-CGN, 02 were crescentic IgA, 01 was crescentic lupus nephritis, 01 was isolated C3 glomerulonephritis, 03 were membranoproliferative glomerulonephritis with diffuse crescent formation and rest 02 were IC-CGN of unknown reason. The glomerular crescents formation was 80.33% in PI-CGN while it was 61.82% among IC-CGN cases and 66.67% in anti GBM glomerulonephritis. Among IC-CGN, 4/9 (44.44%) cases needed dialysis on admission while 5/10 (50%) PI-CGN cases were managed during admission by dialysis. The only anti GBM disease was tried to be managed by frequent dialysis but failed and plasmapheresis was advised but could not be instituted who ultimately succumbed to death following severe haemoptysis. In our study commonest cause of crescentic glomerulonephritis was pauci-immune crescentic glomerulonephritis followed by immune complex mediated glomerulonephritis. While one case of anti GBM glomerulonephritis was found that was possibly a case of Good pasture syndrome.