An Unusual Case of Transplant Kidney Emphysematous Pyelitis and Cystitis

Introduction: Emphysematous cystitis, pyelitis, and pyelonephritis are rare but serious complications of urinary tract infections (UTIs) with gas-producing bacteria. We present a case of emphysematous UTI in a kidney transplant recipient concomitant with rejection. Case Description: A 36-year-old woman with history of end-stage kidney disease of unclear etiology who underwent a living related kidney transplant in 2001 complicated by cellular and antibody-mediated rejection in 2017 and recurrent UTIs presented with worsening kidney function and allograft pain. She initially presented a month prior with allograft pain and dysuria and was treated for Escherichia coli (E. coli) UTI. Computed tomography (CT) and urinalysis 10 days prior to admission were unremarkable. Testing revealed a persistently positive class II donor specific antibody. Kidney biopsy showed chronic active antibody mediated rejection and she was started on high-dose intravenous steroids with plan for therapeutic plasma exchange (TPE). She continued to report significant allograft pain and repeat CT scan demonstrated emphysematous transplant pyelitis and emphysematous cystitis. Antibiotics were started and surgical intervention was not recommended. Repeat urine culture grew E. coli. Further rejection treatment was deferred and she was discharged home with clinical improvement. Her serum creatinine was down to 1.73 mg/dl on discharge from a peak of 2.35 mg/dl during hospitalization. Discussion: This case demonstrates the importance of thorough evaluation prior to initiating treatment for allograft rejection. If this patient had received potent immunosuppression as planned, her emphysematous pyelitis may have progressed to emphysematous pyelonephritis which is associated with increased risk of allograft loss and mortality.Emphysematous pyelitis (yellow arrows) and cystitis (red arrow) on CT.