Article in Japanese

Children with BK virus infection diagnosed by real-time PCR in urine

Sho ISHII¹⁾, Yoshiaki CHO¹⁾, Kahoru FUKUOKA¹⁾, Takayuki YAMANAKA¹⁾, Takemi MURAI¹⁾, Mihoko ISOGAI¹⁾, Yuta AIZAWA¹⁾, Yuho HORIKOSHI¹⁾

The BK virus causes benign diseases from which most humans have asymptomatic or mild infections during childhood, and it becomes latent in urological organs after primary infection. Reactivation in an immunocompromised host can occur in post-hematopoietic stem cell transplant and post-kidney transplant patients. Patients with the BK virus in post-hematopoietic stem cell transplants commonly present with hemorrhagic cystitis or ureteral stenosis. To date, little is known regarding the clinical spectrum of Japanese children with the BK virus. The aim of this study was to describe the clinical characteristics of the BK virus in children with hematuria, and those tested between April 2013 and June 2016 at the Tokyo Metropolitan Children's Medical Center were included in this research. Real time PCR was performed for urinary specimens. Among 17 children (median age 9 years) with hematuria, the BK virus was detected in 7. Four of them had a hematopoietic stem cell transplant and received immunosuppressive therapy. There was no significant difference in characteristics between the BK virus positive and negative group in the hematuria patients, but a tendency of higher age and lower C-reactive protein was observed in the BK virus group (p<0.1). Younger patients were likely to be the BK virus naïve, and the BK virus might trigger less inflammatory response than other causes of hemorrhagic cystitis, which is managed by supportive therapy. Three of the patients in a post- hematopoietic stem cell transplant required platelet transfusion for bleeding control. The BK virus is a differential pathogen especially in immunocompromised children with hematuria.

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1) Department of Infectious Disease Medicine, Tokyo Metropolitan Children's Medical Center

Key words	BK virus, real-time PCR, immunocompromised children, hematopoietic stem cell transplant, hemorrhagic cystitis
Received	February 2, 2017
Accepted	September 4, 2017

29 (4)：316─321,2018