Diagnose This (February 14, 2022)

In a 25yo with sepsis post-cholecystectomy and C. diff colitis, what is your diagnosis?

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The biopsy shows C3 only staining and necrotizing crescentic glomerulonephritis. The findings are consistent with infection-related glomerulonephritis. Paraffin IF (not shown) did not reveal masked immunoglobulin deposits.

Other glomeruli had exudative features (Figure 3). Within the medulla, multifocal hemorrhage and capillaritis were also present, consistent with medullary angiitis (Figure 4 and 5). Although medullary angiitis can be seen in association with infection, given the concomitant presence of focal necrotizing glomerular lesions, ruling out ANCA was also suggested.

References:

Renal medullary angiitis: a case series from a single institution- https://pubmed.ncbi.nlm.nih.gov/23079202