Viral infections in childhood leukemia.

The importance of viral infections in 150 children receiving therapy for leukemia was studied prospectively by application of comprehensive viral diagnostic procedures. One hundred five viral infections were identified, with herpes simplex virus and varicella-zoster virus being the most common agents. The spectrum of viruses associated with serious illness was wider than that in previous studies, and adenoviruses, parainfluenza viruses, rhinoviruses, and enteroviruses were important causes of morbidity. Viral isolation was the most sensitive diagnostic procedure used because complement fixation serology was falsely negative in two-thirds of cases. The occurrence of viral infection may be a previously overlooked important cause of respiratory tract infection and acute pyrexia of unknown origin. Viral infection rates were highest in patients with acute myeloblastic leukemia, in induction and relapse, and in patients treated with newer chemotherapeutic schedules. Thus, viruses are important pathogens in children with leukemia.