The purpose of this study was to characterize a large group of infants with complete
DiGeorge anomaly and to evaluate the ability of thymus
transplantation to reconstitute immune function in these infants.
DiGeorge anomaly is characterized by varying defects of the heart, thymus, and parathyroid glands. Complete
DiGeorge anomaly refers to the subgroup that is athymic (< 1%). The characteristics of 54 subjects at presentation and results from 44 consecutive thymus
transplantations are reported. Remarkably, only 52% had 22q11 hemizygosity and only 57% had
congenital heart disease requiring surgery. Thirty-one percent developed an atypical phenotype with
rash and
lymphadenopathy. To date, 33 of 44 subjects who received a transplant survive (75%) with post-
transplantation follow-up as long as 13 years. All deaths occurred within 12 months of
transplantation. All 25 subjects who were tested 1 year after
transplantation had developed polyclonal T-cell repertoires and proliferative responses to
mitogens. Adverse events developing after
transplantation included
hypothyroidism in 5 subjects and
enteritis in 1 subject. In summary, diagnosis of complete
DiGeorge anomaly is challenging because of the variability of presentation. Thymus
transplantation was well tolerated and resulted in stable immunoreconstitution in these infants.