Pauci-immune crescentic glomerulonephritis in human immunodeficiency virus infection: clinical and therapeutic challenges.

Renal disease in people living with HIV extends beyond classical HIV-associated nephropathy to include immune-mediated and vasculitic lesions, of which pauci-immune crescentic glomerulonephritis is among the rarest and most easily missed. We describe two biopsy-proven cases with anti-myeloperoxidase anti-neutrophil cytoplasmic antibody positivity. The first, established on antiretroviral therapy, presented with a pulmonary-renal syndrome after empirical anti-tubercular treatment had failed; biopsy showed cellular crescents without chronic change, and corticosteroids with rituximab achieved sustained clinical, biochemical and serological remission. The second, antiretroviral-naive, had glomerular haematuria and proteinuria documented at HIV diagnosis and an ischaemic stroke soon afterwards, but declined nephrological assessment; biopsy 3 years later was dominated by global glomerulosclerosis and interstitial fibrosis and he remained dialysis-dependent. The divergence turned on the histological stage at diagnosis rather than antiretroviral status and argues for early biopsy whenever unexplained renal decline with an active urinary sediment occurs in HIV.