Safety and immunogenicity of measles-mumps-rubella vaccine in children with congenital immunodeficiency (DiGeorge syndrome).

Live attenuated vaccines are usually contraindicated in patients with congenital or acquired immunodeficiency. On the other hand, infections due to wild type virus may be particularly severe in patients with low levels of T cells. The aim of the present study was to evaluate safety and immunogenicity of measles-mumps-rubella (MMR) vaccine in children with congenital T cell defect (DiGeorge anomaly). Fourteen patients were included in the study. No severe adverse reaction was reported. No difference between patients and controls was found in frequency of seroconversion for both measles (92.9% versus 96.3%) and rubella (92.9% versus 100%). No difference in mean titres of anti-measles (1.62+/-0.54 versus 1.89+/-0.49 index) (p=0.13) or anti-rubella (78.1+/-48.0 versus 72.0+/-41.0 UI/ml, p=0.68) antibodies was found between patients and controls. No decrease in CD4 cells was detected after immunization. MMR vaccine is immunogenic and can be safely used in patients with DiGeorge anomaly, so preventing severe complication due to wild virus infection.