Background: Autoimmune neutropenia (AIN) can occur in association with autoimmune hemolytic anemia (AIHA) and/or immune thrombocytopenic purpura (ITP), although these associations have not been studied in detail.
Methods and results: Twenty cases of AIN were found in a group of 55 adults with unexplained neutropenia over a five-year period. Eight subjects with AIN had an associated AIHA and/or ITP (AIN+ITP, n = 2; AIN+AIHA, n = 2; AIN+ITP+AIHA, n = 4). Thorough investigations identified no underlying disease in four patients, and none has appeared during follow-up. Of the other 4, one was found to have been suffering from systemic lupus erythematosus when the combined immunocytopenia was diagnosed, one patient from idiopathic myelofibrosis, one from a combined variable immunodeficiency and the other from disseminated tuberculosis. These last three conditions, while sometimes associated with autoimmune cytopenias, has not been previously reported together with combined immunocytopenias. All patients responded to immunosuppressors, although severe infectious complications occurred in two, leading to death from Pneumocystis carinii pneumonia and to irreversible neurologic damage from Listeria monocytogenes meningitis, respectively.
Conclusions: We conclude that combined autoimmune cytopenias are frequently observed in patients with AIN, and a thorough search for associated conditions can lead to unsuspected diagnoses.