Beware of the Patient with Thymectomy: Good's Syndrome in a Patient Presenting with Diarrhea

Good's syndrome is a rare cause of immunodeficiency in adults associated with thymoma. We describe an 80-year-old female with chronic diarrhea, multiple opportunistic infections, and cytopenias. She underwent a thymectomy 5 years ago for a thymoma. Laboratory tests revealed neutropenia, hypogammaglobulinaemia, complete B-cell lymphopenia, and low CD4 T cells with inverted CD4:CD8 ratio, which is consistent with Good's syndrome. We recommend checking immunoglobulin levels in all patients with a history of thymoma. Good's syndrome should be considered as a differential diagnosis if patients present with chronic diarrhea, cytopenias, or recurrent infections. Cytomegalovirus (CMV) infection should be considered in patients with immune deficiency as a cause of chronic diarrhea.