gammopathy /gamop″əthē/ , an abnormal condition characterized by the presence of markedly increased levels of gamma globulin in the blood. Two different types of hypergammaglobulinemia can be distinguished. Monoclonal gammopathy is commonly associated with an electrophoretic pattern showing one sharp, homogenous electrophoretic band in the gamma globulin region. This reflects the presence of excessive amounts of one type of immunoglobulin secreted by a single clone of B lymphocytes. Polyclonal gammopathy reflects the presence of a diffuse hypergammaglobulinemia in which all immunoglobulin classes are proportionally increased. See also Bence Jones protein, multiple myeloma.
