Abstract: PUB208
A Case of Crescentic C3 Glomerulonephritis in a 24-Year-Old Male: A Rare Entity
Session Information
Category: Glomerular Diseases
- 1302 Glomerular Diseases: Immunology and Inflammation
Authors
- Mukku, Venkata Kishore R., The University of Texas Medical Branch at Galveston, Galveston, Texas, United States
- Kochar, Tina, The University of Texas Medical Branch at Galveston, Galveston, Texas, United States
- Jacob, Shancy, The University of Texas Medical Branch at Galveston, Galveston, Texas, United States
- Hussain, Syed A., The University of Texas Medical Branch at Galveston, Galveston, Texas, United States
Introduction
C3 glomerulopathy (C3G) is a clinicopathologic entity secondary to dysregulation of alternative complement pathway in plasma and glomerular microenvironment. C3 glomerulopathies are uncommon forms of glomerulonephritis (GN) characterized by substantial risk of progression to end stage renal disease.
Case Description
24-year-old male with history of hypothyroidism presented to clinic with throat infection and was treated with amoxicillin. Lab work showed worsening renal function and admitted for further work-up which showed negative serologies for Hepatitis B, C, HIV, ANA, ANCA, Anti-ds DNA, cryoglobulin, anti-GBM antibody and complements. Urinalysis revealed microscopic hematuria and random urine protein was 1.3g/g. Patient was initiated on dialysis for worsening renal function and oliguria. He was started on solumedrol and underwent renal biopsy which showed diffuse crescentic glomerulonephritis (GN) on light microscopy. There were 28 glomeruli, 7 of which were globally sclerotic. 15 glomeruli show cellular crescents, 3 of which showed fibrinoid necrosis. There was mild interstitial fibrosis and tubular atrophy. Mesangial and rare subepithelial electron dense deposits were seen on electron microscopy. Immunofluorescence revealed, 1-2 + granular mesangial end glomerular capillary wall positivity for C3 with trace IgM and C4d. These findings are consistent with crescentic C3 GN in the absence of bacterial infection. Patient was started on mycophenolate, steroids and was referred for out-patient genetic testing.
Discussion
The spectrum of clinical manifestations in C3G is wide, from incidental asymptomatic microscopic hematuria to rapidly progressive forms leading to kidney failure. However, most common presentation in clinical setting is proteinuria with preserved kidney function. When the disease is diagnosed in adults, presence of monoclonal gammopathy must be ruled out. Serum C3 hypocomplementemia is a characteristic feature of C3G, although not strictly necessary for the diagnosis. The clinical manifestations of C3G may be preceded by an infection. Hence, a differential diagnosis considering postinfectious GN is mandatory. The therapeutic alternatives available at present can be classified as supportive therapy with angiotensin converting enzyme inhibitors, immunosuppression with steroids, mycophenolate, and anticomplement therapy with eculizumab.