hypogammaglobulinemia

Decreased quantity of the gamma fraction of serum globulin; sometimes used loosely to denote decreased quantity of immunoglobulins in general; associated with increased susceptibility to pyogenic infections. SYN: hypogammaglobinemia.

- acquired h. SYN: common variable immunodeficiency.

- primary h. h. due to a primary immunodeficiency of immunoglobulin-forming cells (B-lymphocytes).

- secondary h. SYN: secondary immunodeficiency.

- transient h. of infancy a type of primary immunodeficiency that occurs in infants of both sexes, usually before the sixth month of life, probably resulting from immaturity of lymphoid tissue. SYN: transient agammaglobulinemia.

- X-linked h., X-linked infantile h. a congenital, primary immunodeficiency characterized by decreased numbers (or absence) of circulating B lymphocytes with corresponding decrease in immunoglobulins of the five classes; associated with marked susceptibility to infection by pyogenic bacteria (notably, pneumococci and Haemophilus influenzae) beginning after loss of maternal antibodies; X-linked recessive inheritance caused by mutation in the Bruton tyrosine kinase gene (BTK) on Xq.

- X-linked h. with growth hormone deficiency h. combined with a reduced number of B cells; characterized by short stature, delayed puberty, and recurrent infections.

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hy·po·gam·ma·glob·u·lin·emia or chiefly Brit hy·po·gam·ma·glob·u·lin·ae·mia -.gam-ə-.gläb-yə-lə-'nē-mē-ə n a deficiency of gamma globulins and esp. antibodies in the blood also a state of immunological deficiency characterized by this

hy·po·gam·ma·glob·u·lin·emic or chiefly Brit hy·po·gam·ma·glob·u·lin·ae·mic -'nē-mik adj

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hy·po·gam·ma·glob·u·lin·emia (hi″po-gam″ə-glob″u-lĭ-neґme-ə) abnormally low levels of all classes of immunoglobulins in the blood; see also agammaglobulinemia, dysglobulinemia, and immunodeficiency.