Herpes zoster frequency and severity in immunocompromised pediatric populations: a structured narrative review.

Background: While herpes zoster (HZ) is known to disproportionately affect people with immunocompromising (IC) conditions, reviews of the frequency and severity of HZ in these conditions have so far been limited to adults. Methods: For this narrative review, we conducted a literature search to identify studies describing HZ frequency in pediatric cohorts with IC conditions including hematopoietic cell transplant, cancer, solid organ transplant, human immunodeficiency virus (HIV), or autoimmune disease commonly treated with immunosuppressants. We also extracted information on HZ complications, when available. Results: Forty-one articles published between 1997 and 2024 from 22 countries were identified. Thirty-four reported risk (cumulative incidence) and 21 reported incidence rates of HZ. The frequency of HZ was elevated in all IC conditions studied compared to that in the general pediatric population. Risk of HZ was particularly high among children receiving HCT (median cumulative incidence: 18%; median follow-up: two years) and children with systemic lupus erythematosus (SLE) (median cumulative incidence: 26%; median follow-up: six years). Children with inflammatory bowel disease had HZ incidence rates approximately three times that of controls. Across all IC conditions, postherpetic neuralgia was less common and resolved faster than in immunocompromised adults, but acute complications were no less common. Varicella vaccination was associated with lower HZ risk in all studies that reported on this intervention. Conclusions: Children with IC and autoimmune conditions, particularly HCT and SLE, develop HZ more frequently and are more likely to experience HZ complications than other children. Varicella vaccination appears to reduce these risks.