Sternheimer-Malbin Staining to Detect Decoy Cells in Urine of 213 Kidney Transplant Patients

Human polyoma virus–associated nephropathy frequently refers to allograft failure after kidney transplant. Thus, the early detection of viral activation is extremely important for these immunocompromised patients. Previously, urine polyoma virus–infected cells (decoy cells) were indicated as the virus action, usually screened by the routine papanicolaou cytology in renal biopsy, but these methods are complex and the positive rate is low. In this article, the direct microscopy observation method, Wright-Giemsa staining, and Sternheimer-Malbin (SM) staining were all used to screen the decoy cells in urine samples of 213 kidney transplant patients who had used immunosuppressive drugs. Among them, decoy cells were detected in 40 cases (18.8%) by the direct observation method, 44 cases (20.7%) by Wright-Giemsa staining and 49 cases (23.0%) by SM staining. Furthermore, the most common polyoma viruses, BK and JC viruses, were also confirmed in 41 (83.7%) cases among these 49 decoy cell–positive samples. Importantly, compared with other decoy cell detection methods, SM staining is fast, easy to operate, and has a high positive rate. Therefore, SM staining is recommended as a fast and effective method for screening urine decoy cells in kidney transplant patients. •SM staining could be an effective method for screening urine decoy cells in kidney transplant patients.•Compared with the direct microscopy observation method and Wright-Giemsa staining, SM staining is fast, easy to operate, and has a high positive rate.