Live vaccine use and safety in DiGeorge syndrome

Live vaccines are generally contraindicated in patients with DiGeorge syndrome (DGS), a congenital disorder characterized by cellular immune deficiency. Vaccine utilization and safety in this population are not well described. This study examined vaccination patterns and adverse events following live immunization (AEFLI) in these individuals.

A multicenter retrospective cohort study was conducted in subjects with DGS confirmed by fluorescence in situ hybridization assay (chromosome 22q11.2 microdeletion). Live vaccine-preventable illnesses, vaccination coverage and timeliness, and AEFLIs in the 56-day window after live vaccination were examined. Bivariate and multivariable analyses assessed the impact of demographics medical history, timing of diagnostic confirmation, and preceding immune function on vaccination patterns and AEFLIs.

Of 194 subjects, 77% and 75% received measles-mumps-rubella (MMR) and varicella vaccines, respectively; 58% completed recommended vaccinations by age 19 to 35 months. Adverse events occurred after 14% and 20% of MMR and varicella vaccine doses, respectively. Most events were minor, few were serious, and no deaths were reported in post-live vaccination windows. Although early diagnostic confirmation negatively affected live vaccination coverage and timeliness (P < .001), baseline CD4% did not differ between subjects who did or did not receive live vaccines by 12 to 18 months. Among varicella vaccine recipients, those with a subsequent adverse event had a lower preceding CD4% (24.8% ± 7.3%) than those without (35.5% ± 11.7%) (P < .05); no CD4% differences were observed with MMR vaccination. Fourteen unvaccinated subjects experienced live vaccine-preventable illnesses.

Live vaccines were frequently given and generally well-tolerated among patients with DGS with mild-to-moderate immunosuppression.