Immunoglobulins G, A, and M in Systemic Lupus Erythematosus

Seventeen whites, eight Negroes and one American Indian with systemic lupus erythematosus were examined immunologically and clinically. These patients exhibited a mean elevation of gamma G globulins that was disproportionately high when compared with their gamma A and gamma M levels. The elevations of the gamma G globulins correlated with the degree of anemia and, in the white patients, with the quantity of protein precipitating as euglobulin. Also, in this group proteinuria correlated with degree of elevation of gamma G and euglobulins. When antibodies to gamma G globulins (latex test) were found, it was generally (seven of eight cases) in those with elevated gamma G levels. Those patients with the lowest complement titers generally had more acute disease. The possible significance of the disproportionate elevation of the gamma G globulins as a reflection of a fundamental abnormality in lupus is discussed.