Urinary BK Virus Excretion in Children Newly Diagnosed with Acute Lymphoblastic Leukemia

BACKGROUND Determining the risk factors in developing or increasing the relapses of acute lymphoblastic leukemia (ALL) may help health and preventive systems to launch new programs. Up to 90% of normal population changes to seropositive for BK virus by the age of 10 years. Whether this oncogenic virus is responsible for evolving ALL is unclear. In this study, we evaluated the excretion of urinary BK virus in newly diagnosed children with ALL compared with normal population. METHODS This case-control study was carried out on 62 participants (32 ALL patients and 32 normal subjects), aged 1-18 years, in Saint Al-Zahra and Sayyed-Al-Shohada University Hospitals, Isfahan, Iran. A polymerase chain reaction (PCR) method was used to detect the BK virus in specimens. PCR amplification was performed using specific primers of PEP-1 (5'-AGTCTTTAGGGTCTTCTACC-3') and PEP-2 (5'-GGTGCCAACCTATGGAACAG-3'). RESULTS Thirty-five out of 62 participants (54.8%) were males and the remaining were females. The mean duration of disease was 9.6 ± 9.69 months. Central nervous system (CNS) relapse was seen in 29% of the patients. Positive PCR for urine BK virus was seen in three children with ALL (9.7%). No positive result for urine BKV was achieved in the control group. However, Fisher's exact test did not show any significant difference between the two groups (P > 0.05). In addition, there was no significant correlation between BKV positivity and frequency of relapses. CONCLUSION To demonstrate the role of BK virus in inducing ALL or increasing the number of relapses, prospective studies on larger scale of population and evaluating both serum and urine for BK virus are recommended.