Previous studies show that the presence of autoantibodies, particularly SSa, can predict the development of Sjogren’s Syndrome by as many as 18 years. A new study from Harvard University shows that elevated levels of immunoglobulin G (IGg), a condition known as hypergammaglobulinemia, can also be used to predict autoimmune disease development. Autoantibodies are made from immunoglobulins. 

In the 10-year study involving 442 patients with elevated IgG levels, fifty percent of the patients eventually developed an autoimmune or auto inflammatory disease, most frequently systemic lupus erythematosus (SLE) or related connective tissue disorders and inflammatory bowel diseases. Patients who developed autoimmune disorders were also found to initially have had higher IgG levels, lower white blood cell counts, lower hemoglobin levels, and lower C-reactive protein (CRP) test results.  In female patients, a higher IgG level, lower white blood cell count, anemia and a normal CRP were 95 percent predictive of an underlying autoimmune disorder. Girls with hypergammaglobulinemia were three times as likely as boys to develop an autoimmune disease.  In adults, an elevated IgG usually signals autoimmunity, liver disease, cancer or infection. In children, this same pattern for hypergammaglobulinemia may not be true. At this time, researchers conclude that the finding of hypergammaglobulinemia in children in the absence of malignancy or infection is suggestive of an underlying autoimmune disease.

Source: Nancy Walsh, Med Page Today, November 12, 2013. “Hypergammaglobulinemia in the pediatric population as a marker for underlying autoimmune disease: a retrospective cohort study.