Transient hypogammaglobulinemia of infancy: need to reconsider name and definition.

Twenty-three infants with diminished levels of one or more immunoglobulin isotypes, intact antibody producing capacity, and a generally benign clinical course were initially diagnosed as having transient hypogammaglobulinemia of infancy. Prospective evaluation of these infants, including seven to age 60 months, revealed that acquisition of normal immunoglobulin levels was often delayed beyond infancy. In some cases the diminished immunoglobulin levels were a prodrome of selective lgA deficiency. These children seemed to experience frequent sinopulmonary infections early in life, but fewer with age. None of these children received exogenous gammaglobulin. The designation of transient hypogammaglobulinemia of infancy is a misnomer, and the diagnosis, even if accepted, can be made only in retrospect. The alternative designation hypogammaglobulinemia of early childhood is suggested, to which can be added "with recovery" or "with development of other dysgammaglobulinemia," depending on the eventual phenotype observed.