Clinical and immunophenotypic features of atypical complete DiGeorge syndrome.

[omenn syndrome]

DiGeorge syndrome is a congenital malformation characterized by variable defects of the thymus , heart and parathyroid glands . Athymic patients are classified as exhibiting complete DiGeorge syndrome . Some of these patients may also exhibit oligoclonal T -cell expansion , generalized rash and lymphadenopathy at some point after birth . This rare condition is known as atypical complete DiGeorge syndrome , resembles Omenn syndrome , and has not been fully characterized .The clinical and immunophenotypic features of atypical complete DiGeorge syndrome were assessed in two affected Japanese infants . T -cell receptor (TCR ) Vβ repertoire was analyzed on flow cytometry and complementarity-determining region 3 spectratyping .Both patients had no detectable thymus tissue and profound T -cell lymphopenia soon after birth . Progressive increase of activated T cells , however , as well as eosinophilia , high serum IgE level , generalized rash , and lymphadenopathy were observed during early infancy . A highly restricted TCR Vβ repertoire was demonstrated both in CD 4 (+) and CD 8 (+) T cells .T he Omenn syndrome -like manifestations might be associated with the oligoclonal proliferation of activated T cells . Analysis of the immunophenotype and TCR Vβ repertoire is helpful to establish the early diagnosis of atypical complete DiGeorge syndrome .