Case report and literature review on Good's syndrome, a form of acquired immunodeficiency associated with thymomas.

Thymoma is an uncommon and slow-growing neoplasm that usually presents with mass-associated respiratory symptoms, superior vena cava syndrome or parathymic syndromes. We present a patient with thymoma and hypogammaglobulinemia who had recurrent sinopulmonary infections and diarrhea, recognized to be Good's syndrome. A 75-year old male with thymoma was admitted in our institution due to severe dehydration secondary to a 2-week history of non-bloody watery diarrhea refractory to anti-motility medications. His condition started 3 years ago when he had repeated outpatient visits and hospital admissions either from diarrhea or respiratory tract infections. Workup was essentially unremarkable except for low serum IgM and IgG, lymphocytopenia, and a low absolute CD4 T cell count of 94. A diagnosis of Good's syndrome was made. Patients with Good's syndrome usually have low to absent B cells in the peripheral blood, hypogammaglobulinemia, and cell-mediated immunity defects. Immunologic investigations, T cell subsets, B cell, and quantitative immunoglobulins should be considered a part of diagnostic search in patients with thymoma with recurrent infections or diarrhea. Thymectomy has favorable effects on other parathymic syndromes but is ineffective in improving immunologic deficiencies in this syndrome. Immunoglobulin replacements have been reported to decrease infections, reduce hospitalizations, and decrease antibiotic use in these patients. Clinical outcomes depend on the severity of infections, associated hematologic and autoimmune diseases rather than the thymoma itself.