Transient hypogammaglobulinemia of infancy is a temporary decrease in serum IgG and sometimes IgA and other Ig isotypes to levels below age-appropriate normal values.
In transient hypogammaglobulinemia of infancy, IgG levels continue to be low after the physiologic fall in maternal IgG at about age 3 to 6 mo. The condition rarely leads to significant infections and is not thought to be a true immunodeficiency.
Diagnosis is based on low serum Ig levels and tests showing that antibody production in response to vaccine antigens (eg, tetanus, diphtheria) is normal. Thus, this condition can be distinguished from permanent forms of hypogammaglobulinemia, in which specific antibodies to vaccine antigens are not produced.
IV immunoglobulin is unnecessary. This condition may persist for months to a few years but usually resolves.
Last full review/revision September 2008 by Rebecca H. Buckley, MD