Subacute large bowel obstruction as an unusual presentation of selective IgA deficiency.

Nodular lymphoid hyperplasia (NLH) is a rare, benign condition of lymphoid proliferation within the gastrointestinal tract. NLH is a recognized feature of specific immunodeficiency syndromes, including common variable immunodeficiency and selective IgA deficiency. NLH may develop throughout the gastrointestinal tract; however, it usually develops in the small intestine. We report an extremely unusual case of previously undiagnosed selective IgA deficiency presenting with subacute rectosigmoid obstruction.