Systemic BK Virus Infection in a Pediatric Patient With Severe Combined Immunodeficiency.

Human BK virus (BKV) infection is known to occur mostly during childhood with the establishment of latent infection with no tissue damage or clinical manifestations. However, conditions causing immunosuppression can lead to increased virus replication and tissue damage. Although the tissues most commonly involved are the kidneys, bladder, ureters and, to some extent, brain tissue, there are some reports that suggest that BKV may cause multisystemic infections. In this case, a 12-month-old child was seen to suffer from multiple gastrointestinal infections. This prompted a search for immunodeficiencies, which revealed the presence of severe combined immunodeficiency. The child was eventually hospitalized and continued showing recurrent bouts of gastroenteritis as well as lower respiratory infection. After multiple antibiotic courses, he developed acute kidney injury, a hemophagocytic syndrome, and eventually respiratory failure, which led to his death a year later. Autopsy findings revealed the presence of a disseminated BKV infection involving the kidneys, ureters, leptomeninges, and pancreas. Analysis of the literature failed to show any previous case of BKV pancreatitis. The present case suggests that BKV can damage more tissues than previously reported and may be responsible for systemic infections in immunosuppressed patients.