Immunoglobulin deficiency, especially deficiency of IgA, has been described in patients with celiac sprue (CS). Our study was performed in an area of high prevalence of CS to determine the prevalence of immunodeficiency states in patients with CS, to examine their clinical characteristics, response to treatment, and HLA phenotypes compared with a group of age- and sex-matched persons with CS but without immunoglobulin deficiency. Fourteen of 604 patients with CS were identified as being selectively deficient in IgA, whereas one had common variable immunodeficiency. At diagnosis, anemia was present in 8 of 14 IgA-deficient patients compared with 10 of 42 controls (p = 0.047), whereas abdominal pain was more common in controls with CS. Autoimmunity and recurrent infection were more prevalent in the IgA-deficient group. Response to gluten-free diet was similar in both groups in terms of histologic structure and recovery of intestinal brush-border enzyme activity. IgA-deficient participants with CS had no increased risk of associated malignancy or lymphoma. HLA phenotypes were similar in both groups. The prevalences of selective IgA deficiency and common variable immunodeficiency in this series of patients with CS are 2.31 in 100 and 0.16 in 100, respectively. Although this group is unique in character, close follow-up coupled with conscientious compliance with a gluten-free diet, remains the mainstay of treatment for these patients.