Recurrent infection-induced autoimmune haemolytic anaemia complicated by pulmonary embolism: a case report and literature review

A 73-year-old woman presented with progressive dyspnoea up to type 1 respiratory failure. Laboratory values showed leucocytosis, reduced haemoglobin to 71 g/L, elevated indirect serum bilirubin and lactic dehydrogenase. Computed tomography pulmonary angiography (CTPA) revealed peripheral pulmonary embolism (PE). Echocardiography showed enlarged right ventricle, elevated estimated pulmonary arterial systolic pressure (57.2 mmHg) and normal left ventricular ejection fraction. The patient was diagnosed with autoimmune haemolytic anaemia (AIHA), which was induced by recurrent infections without standard treatment in the past year. AIHA is the cause of PE due to the absence of common predisposing factors and other thrombophilia. The patient became better after administration of glucocorticoids, intravenous immunoglobulin and rivaroxaban.