Utility of urinary cytology for diagnosing human polyoma virus infection in transplant recipients: A study of 37 cases with electron microscopic analysis

Human polyoma virus (HPOV) infection is associated with hemorrhagic cystiti s, tubulointerstitial nephritis, and renal transplant dysfunction/allograft loss. We evaluated the utility of cytologic examination to detect HPOV inf ection in 37 urinary cytology (UC) samples (3 bladder washings, and 34 void ed samples) from 29 transplant patients, compared to electron microscopic s tudies (EMS). Evidence of viral infection was found in I I specimens (30%). Five cases were diagnosed as HPOV by both UC and EMS. One was positive for HPOV by EMS only. Two cases diagnosed as HPOV by UC were demonstrated to b e adenovirus (AV) with EMS. Two cases diagnosed as cytomegalovirus (CMV) by , EMS had negative UC One was called HPOV by UC; EMS in this case was negat ive. Compared to EMS, the sensitivity and specificity of UC for detecting H POV were 83% and 90%, respectively, with a positive predictive value of 63% , and a negative predictive value of 96%. We conclude that UC is a relative ly sensitive and specific method for detecting active HPOV infection in tra nsplant patients, and is important in light of the clinical significance of HPOV infection in transplant recipients. The sensitivity and accuracy of U C for diagnosing HPOV can be increased by adding EMS. (C) 2001 Wiley-Liss, Inc.