A 32‐year‐old West African man with a history of malaria presented to the ER with dizziness, severe fatigue, palpitations, and dyspnea on exertion. On initial assessment, he was found to have sublingual icterus, bounding peripheral pulses, tachycardia, and a loud systolic murmur. Chest x‐ray revealed bilateral hazy lung opacities and laboratory values were notable for hemoglobin (Hgb) 5.5 g/dL, nucleated RBCs 58%, LDH 1084 IU/L, and haptoglobin < 5 mg/dL Blood and urine cultures were negative as were smears for parasites. Direct Coombs' test was positive, and warm IgG autoantibodies were detected. Consequently, the patient was diagnosed with warm autoimmune hemolytic anemia (WAIHA). The patient was initiated on high‐dose prednisone and transfused with 4 units of O‐incompatible pRBCs, which increased Hgb to 9.5 g/dL Subsequent testing revealed HIV‐1 positivity with a CD4 count of 932 cells/μL and a viral load of 145,715 copies/mL. Hepatitis B core antibody and surface antigen were also positive, with a viral load of 667 IU/mL. High‐dose prednisone therapy was supplemented with intravenous immunoglobulins (IVIG) to accelerate long‐term recovery. As an outpatient, the patient was started on emtricitabine‐tenofovir and raltegravir. Two months after diagnosis, he completed steroid treatment with a stable Hgb of 13.8 g/dL and HIV‐1 and HBV viral loads of 29 copies/mL and undetectable, respectively.
HIV usually presents acutely with a mononucleosis‐like retroviral syndrome or with opportunistic infections characteristic of AIDS. In this patient, HIV‐1 infection presented with WAIHA in what would have normally been the clinically latent stage of disease. HIV‐1 infection, known to cause immune deregulation, has been linked to many hypergammaglobulinemia‐associated autoimmune phenomena, the most common being SLE, ITP, and APLS. Clinically overt WAIHA, however, is an exceedingly rare presentation. WAIHA is a rare autoimmune disorder characterized by auto‐antibody‐mediated lysis of RBCs in circulation. Clinical symptoms result from the acute anemia and the compensatory hyperdynamic state. It is most commonly idiopathic, but can be precipitated by autoimmune diseases, lymphoid cancers, certain drugs, alloreactions, and viral infections — as in this case. Short‐term morbidity and mortality usually results from pulmonary edema, myocardial infarction, or fatal arrhythmias. First‐line therapy is high‐dose corticosteroids tapered over weeks to months, but additional salvage therapies include splenectomy and immunomodulatory agents such as azathioprine, rituximab, or IVIG.
Hospitalists should be aware of known risk factors for developing WAIHA for appropriate identification of codiagnoses. Severe cases of WAIHA can be lethal and should be managed aggressively with a blood bank worker as a liaison. HIV‐1‐induced immune deregulation can precipitate a wide variety of autoimmune phenomena.