Renal Phaeohyphomycosis: Aureobasidium Pullulans Infection Caused by Instrument Inoculation in a Healthy Patient - A Case Report

Abstract

Introduction: Aureobasidium pullulans, ablack yeast-like dematiaceous fungus. Most ofthese infections commonly affect the immunocompromised patients; however, post-instrument inoculation was extremely rare. This is the first report of renal phaeohyphomycosis by A. pullulans after stone surgeries reported worldwide, despite a thorough literature review. Case Report: A 29-year-old immunocompetent native lady, with underlying bilateral grade II renal parenchymal disease, was referred for right staghorn calculi and big left ureteric stone with bilateral hydronephrosis back in 2016. She underwent right percutaneous nephrolithotripsy (PCNL) and left ureteroscopic surgery (URS). Intra-operatively, 90% stone clearance for the right kidney and complete stone clearance was achieved over the left ureteric stone. Blood investigation showed Urea was 8.1 and Creatinine was 200 respectively. There was no growth in Urine C+S sent intraoperatively. Post-operatively, she did a DTPA scan which showed moderate impaired right kidney function (28ml/min-69%) with a non-functioning left kidney (13ml/min-13%). Her condition and renal function had been closely monitored during follow-up in the urology clinic. During follow-up, computed tomography urography (CTU) reassessment in 2018 showed residual right renal stones and resolved left hydronephrosis. Subsequently, she underwent right retrograde intrarenal surgery (RIRS) and ureteric stenting. Intraoperatively, complete stone clearance for the right upper and middle pole; there were a few blackish tubular foreign bodies seen at the right lower pole which were extracted and sent for investigations. Interestingly, the histopathology (HPE) reported as blood clots while the fungal PCR done by the Institute for Medical Research (IMR) showed Aureobasidium pullulans DNA detected. Post-operatively, she completed a one-month course of anti-fungal antibiotic and was discharged home well. Subsequent urine culture was cleared and CTU assessment showed no evidence of stone recurrence or foreign bodies. Discussion and Conclusion: Renal phaeohyphomycosis caused by Aureobadium pollulans secondary to post-instrument inoculation is first reported worldwide in an immunocompetent native lady.