Gram-negative sepsis following biopsy of a transplant recipient with asymptomatic allograft pyelonephritis.

Pyelonephritis post-renal transplantation is common and in up to 50% of cases can be asymptomatic. Transplant pyelonephritis shares a lot of histopathological features with acute cellular rejection. We present a case of asymptomatic acute graft pyelonephritis where a renal biopsy was complicated by sepsis, and discuss the difficulties in interpretation of renal histology in the setting of transplant pyelonephritis where rejection may also be a possibility, but differentiation is challenging.