Abstract: FR-PO720
Infection-Related Rapidly Progressive Crescentic Glomerulonephritis
Session Information
- Glomerular Diseases: From Inflammation to Fibrosis - II
November 03, 2023 | Location: Exhibit Hall, Pennsylvania Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1401 Glomerular Diseases: From Inflammation to Fibrosis
Authors
- Henderson, Jacob R., The Christ Hospital, Cincinnati, Ohio, United States
- Pembaur, Karl Berthold, The Christ Hospital, Cincinnati, Ohio, United States
Introduction
Rapidly progressive crescentic glomerulonephritis (RPGN) is characterized by progressive loss of renal function. Most cases are diagnosed with a renal biopsy. Here we examine a subtype of RPGN in the setting of IV drug abuse, hepatitis C, and tricuspid valve (TV) MRSA endocarditis.
Case Description
A 32 year-old male with a PMHx significant for IVDU presented with fever, chills, lower extremity edema, and a dark discoloration to his urine. The patient had a new acute kidney injury (AKI) (Cr 1.66, BUN 35), anemia (Hgb 11.2), and leukocytosis (WBC 16.8k). Total protein and albumin were low. Urinalysis revealed hematuria (30 RBC’s and RBC casts), proteinuria (300mg/dL), small leukocyte esterase, 41 WBC’s and a urine protein to creatine ratio of 4.4mg/g. Blood cultures were positive for MRSA, and TEE revealed TV endocarditis. Hepatitis testing revealed a chronic, active hepatitis C infection and a cleared hepatitis B infection, HIV testing was negative. He underwent TV thrombectomy for vegetation removal and was initiated on antibiotics. Renal function worsened and an ANA, dsDNA, Anti-GBM, SPEP, and cryoglobulin were negative. An atypical P-ANCA was positive with a 1:40 titer, complements C3 and C4 were low. Renal biopsy was performed, and light microscopy revealed 61% crescents with focal segmental necrosis, and mesangial expansion. IF microscopy revealed mesangial staining of 1+ IgG/IgA/IgM/C1q, 3+ C3, and 3+ kappa & lambda.
Discussion
The biopsy was consistent with a necrotizing, crescentic glomerulonephritis with mild interstitial fibrosis. The atypical P-ANCA seropositivity was thought to be due active hepatitis C infection. In the context of MRSA bacteremia, active hepatitis C infection, and chronically inactive hepatitis B infection with rapid progression of renal impairment, the patient was diagnosed with an infection related RPGN. Treatment was directed at the underlying cause of infection, however due to rapid progression of renal injury, and degree of proteinuria, he was started on a steroid taper. This patient will be treated for hepatitis C in the outpatient setting. In the context of an active infection and clinical evidence of RPGN, a renal biopsy should be performed for a definitive diagnosis. While treating the underlying infection is appropriate, immunosuppression should be considered in the right clinical context, in this case, rapidly progressive renal failure.