AP-VAS 2012 case report: a case of ANCA-negative crescentic glomerulonephritis complicating multiple opportunistic infections in the digestive tract.

Crescentic glomerulonephritis (GN) is one of the common causes of rapidly progressive glomerulonephritis (RPGN). Pauci-immune crescentic GN is usually associated with anti-neutrophil cytoplasmic antibody (ANCA). However, patients with pauci-immune crescentic GN who lack ANCAs have recently been reported. Approximately 10-30 % of patients with pauci-immune crescentic GN lack ANCAs. The clinical characteristics of patients with ANCA-negative pauci-immune crescentic GN are not entirely the same as patients with ANCA-positive GN, and this suggests that ANCA-negative and ANCA-positive pauci-immune crescentic GN might be different disease entities. We report a patient with ANCA-negative crescentic GN complicated with multiple opportunistic infections (Candida albicans, herpes simplex virus, and Cytomegalovirus) in the digestive tract during the course of immunosuppressive therapy. After antifungal and antiviral therapies including itraconazole, valaciclovir, and ganciclovir, she recovered from multiple opportunistic infections. The occurrence of comorbid opportunistic infections during the course of immunosuppressive therapy may not be rare in the elderly. However, a case of multiple opportunistic infections limited to the digestive tract is very rare.