Asian Journal of Medical Research and Case Reports

Introduction: Common variable immunodeficiency (CVID) is the most common primary immunodeficiency and is characterised by impaired immunoglobulin production, particularly decreased IgG levels. Although recurrent infections are the main clinical manifestation, autoimmune disorders are also frequently reported and may occasionally be the first indication of the disease. Autoimmune haemolytic anaemia (AIHA) is among the most important autoimmune complications and may sometimes precede the diagnosis of CVID.

Case Report: We report the case of a 42-year-old woman with insulin-treated diabetes mellitus, severe rheumatic mitral regurgitation, atrial fibrillation, and AIHA diagnosed in 2018. The initial episodes were successfully managed with high-dose corticosteroids and azathioprine. Seven years later, she developed severe, poorly tolerated anaemia that became refractory to high-dose corticosteroid therapy. Extensive investigations excluded connective tissue disease, thrombotic microangiopathy, haematological malignancy, haemoglobinopathy, thyroid dysfunction, and several infectious causes. Serum protein electrophoresis demonstrated profound and persistent hypogammaglobulinaemia, associated with marked B-cell lymphopenia and reduced levels of IgG, IgA, and IgM. A history of recurrent severe infections, including recurrent tonsillitis complicated by rheumatic fever, necrotising fasciitis, and herpes zoster, further supported the diagnosis of CVID. Azathioprine was discontinued, corticosteroids were gradually tapered, and antibiotic prophylaxis was initiated. Immunoglobulin replacement therapy was considered.

Discussion: The association between CVID and AIHA highlights the complex interplay between immunodeficiency and autoimmunity. Impaired B-cell tolerance, defective regulatory T-cell function, an imbalance between regulatory and follicular helper T cells, and abnormalities within the splenic microenvironment may contribute to the persistence of autoreactive B cells and pathogenic autoantibody production. Chronic inflammatory pathways may further sustain this immune dysregulation.

Conclusion: AIHA may be an initial or revealing manifestation of CVID. In patients with autoimmune cytopenia, particularly when associated with recurrent severe infections or unexplained hypogammaglobulinaemia, underlying immunodeficiency should be considered. Early recognition of this association is important for appropriate management of both the autoimmune complication and the underlying immune disorder.