The epidemiology of herpes zoster in 226 children with acute lymphoblastic leukemia

Area of Science:

• Pediatric Oncology
• Infectious Diseases
• Hematology

Background:

• Herpes zoster (HZ) is uncommon in healthy children but frequently observed with severe courses in pediatric patients undergoing chemotherapy.
• Acute lymphoblastic leukemia (ALL) treatment protocols can increase HZ incidence and morbidity.
• This study investigates HZ-related morbidity in children diagnosed with ALL.

Purpose of the Study:

• To determine the morbidity associated with Herpes zoster (HZ) in children diagnosed with acute lymphoblastic leukemia (ALL).
• To analyze the incidence and characteristics of HZ eruptions during different phases of ALL treatment, including primary chemotherapy, relapse therapy, and bone marrow transplantation (BMT).

Main Methods:

• Retrospective review of medical records for 226 children diagnosed with ALL.
• Identification of 160 seropositive children at diagnosis.
• Registration of HZ eruptions during primary chemotherapy, relapse therapy, and post-BMT, noting treatment with acyclovir (ACV).

Main Results:

• 90 HZ eruptions were recorded in 14 children, including recurrent episodes.
• 47 children (29%) experienced HZ during primary chemotherapy, with higher rates in high-risk protocols.
• HZ incidence was 24% during relapse therapy and 35% following BMT, with complications like cutaneous dissemination (11 cases) and postherpetic neuralgia (5 cases).

Conclusions:

• Nearly one-third of seropositive children with ALL experienced HZ during primary chemotherapy.
• Children on intensive, high-risk protocols faced a higher likelihood of recurrent HZ eruptions.
• While complicated HZ is infrequent, prolonged chemotherapy increases morbidity; post-remission vaccination strategies warrant consideration.