ABSTRACT
A possible temporal correlation between high BK virus [BKV] load in urine alone or in combination with acute graft versus host disease [GVHD] and the development of hemorrhagic cystitis [HC] was examined in this study. 31 allogeneic hematopoietic stem cell transplanted [SCT] patients were included in this study. BKV DNA was detected by nested and quantitative Real-Time PCR in the urine of 16 out of 31 patients. HC occurred in 6/16 patients with BKV DNA in their urine samples. BKV load was evaluated in the urine samples from 5 of 6 HC patients. Presence of BKV or BKV load >10[6] copies alone in urine samples showed some predictive ability for HC, while acute GVHD alone or conditioning regiments did not. However, during the period after SCT to HC onset a combination of BKV load >10[6] copies and acute GVHD, discriminated the best between HC [4/5] and non-HC [2/25] patients [p=0.003]. This study indicates that BKV DNA and particularly >10[6] BKV copies/microl of urine from SCT patients may have some predictive ability for HC. However, the best association to HC was achieved when a viral load of > 10[6] BKV copies/microl of urine was present in combination with acute GVHD