Abstract: PO2261
An Unusual Case of Granulomatous Interstitial Nephritis (GIN)
Session Information
- Pathology and Lab Medicine: Clinical
October 22, 2020 | Location: On-Demand
Abstract Time: 10:00 AM - 12:00 PM
Category: Trainee Case Report
- 1602 Pathology and Lab Medicine: Clinical
Authors
- Whitney, Charis Elizabeth, University of Florida Health Science Center Jacksonville, Jacksonville, Florida, United States
- Mars, Ronald L., University of Florida Health Science Center Jacksonville, Jacksonville, Florida, United States
Introduction
A 28 Y/O man was admitted with stage 5 CKD. He was entirely asymptomatic with a negative PMH except for recent HTN & proteinuria. Entire proteinuria w/u was negative. PE was unremarkable. Kidney biopsy showed advanced glomerulosclerosis wtih chronic non-caseating GIN. Etiology was uncertain except for history of BCG vaccination. BCG induced GIN was proposed. He was given a trial of ACE-I's, but ultimately required long term hemodialysis (HD).
Case Description
A 28 Y/O Hispanic male with 1 yr PMH of untreated HTN & proteinuria presented with BUN 88, Cr 7.85. 1 day after foot surgery Cr increased to 8.14 & Renal was consulted.
1 yr ago he was diagnosed with HTN & proteinuria but never received f/u or treatment. PMH was negative. FH was significant for a cousin with ESRD s/p kidney transplant & an uncle with diabetes.
Full proteinuria w/u was (-). Renal US revealed normal size kidneys & increased cortical echogenicity c/w medical renal disease. He was started on lisinopril with improvement in BP, but no improvement in renal function & was then started on HD.
Kidney biopsy revealed acute tubular injury without regeneration changes, acute & chronic interstitial nephritis with a few granulomas, 75% global glomerulosclerosis, mild tubular atrophy & interstitial fibrosis. GMS & AFB stains were negative for fungus & mycobacteria. No electron dense deposits (EDD's) were see on electron microscopy. Further discussion with patient revealed he received BCG vaccine when 2 weeks old.
Discussion
Bacillus Calmette-Guerin (BCG) vaccine is a live but attenuated strain of Mycobacterium bovis used to protect against TB in many countries with a high prevalence of TB. BCG has been implicated in the development of granulomatous disease in multiple organs, but rarely in the kidneys. Our patient received an intra-dermal BCG injection 2 wks after birth & had no sequelae or side effects. The historical (-) PMH, absence of prior medications or infectious process, (-) serologic w/u, (-) history of environmental exposures made the incidental discovery of asymptomatic stage 5 CKD with proteinuria all the more surprising.
The unexpected finding of GIN raised the consideration for stimulated immunity & granuloma formation from latent BCG vaccine. While literature documents granuloma formation in other organs, its occurrence in kidneys & potential contribution to progressive CKD seems less common, but should not to be overlooked.