AGAMMAGLOBULINEMIA

n. lack of hemoglobin in the blood (Medical)

X-linked agammaglobulinemia (also called X-linked hypogammaglobulinemia, XLA, Bruton type agammaglobulinemia) is a rare X-linked genetic disorder that affects the body's ability to fight infection (origin of the name: A=no, gammaglobulin=Antibody). XLA patients do not generate mature B cells. B cells are part of the immune system and normally manufacture antibodies (also called immunoglobulins) which defends the body from infections (the humoral response). Patients with untreated XLA are prone to develop serious and even fatal infections. Patients typically present in early childhood with recurrent infections, particularly with extracellular, encapsulated bacteria. XLA is an X-linked disorder, and therefore is almost always limited to males. It occurs in a frequency of about 1 in 100,000 male newborns, and has no ethnic predisposition. XLA is treated by infusion of human antibody. Treatment with pooled gamma globulin cannot restore a functional population of B cells, but it is sufficient to reduce the severity and number of infections due to the passive immunity granted by the exogenous antibodies.
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Agammaglobulinemia /agam·ma·glob·u·lin·emia/ absence of all classes of immunoglobulins in the blood. See also hypogammaglobulinemia. [more]Agammaglobulinemia - Community and Resources

Noun
1. a rare immunological disorder characterized by the virtual absence of gamma globulin in the blood and consequent susceptibility to infection
(hypernym) immunodeficiency

Total (or nearly total) absence of the infection-fighting proteins (immunoglobulins) belonging to the class called gamma globulins. Can be due to certain genetic diseases or to acquired diseases such ad HIV.