Objectives: The aim of this study was to evaluate the frequency of autoimmunity in primary antibody deficiency (PAD).
Methods: A total of 471 patients with PADs enrolled in this retrospective cohort study. For all patients' demographic information, clinical records and laboratory data were collected to investigate autoimmune complications.
Results: Autoimmune disorders as the first presentation of immunodeficiency were recorded in 11 patients (2.5%). History of autoimmunity was recorded in 125 patients during the course of the disease (26.5%). The frequency of autoimmunity in common variable immune deficiency (32.0%) was higher than other forms of PADs. The most common autoimmune manifestations were reported to be autoimmune gastrointestinal disease and autoimmune cytopenias. Among patients with autoimmunity, 87 patients (69.6%) had a history of one autoimmune disorder, while 38 patients (30.4%) had a history of multiple autoimmunities. The immune thrombocytopenic purpura and autoimmune hemolytic anemia were the most two concomitant autoimmune disorders in 16 (42.1%) of 38 patients with multiple autoimmunities. Comparing the frequency of Tregs in PAD patients with autoimmunity showed that, patients with multiple autoimmunities had lower Tregs than those with single autoimmunity (p = 0.017).
Conclusion: It is important that non-immunologist physicians be alert of the associated autoimmunity with PADs in order to reduce the diagnostic delay and establish timely immunoglobulin replacement therapy in these patients.
Keywords: Primary antibody deficiencies; autoimmune hemolytic anemia; autoimmunity; immune thrombocytopenic purpura.