Visceral leishmaniasis mimicking inflammatory myositis that led to haemophagocytic lymphohistiocytosis.

Abstract

Idiopathic inflammatory myositis (IIM) is a heterogeneous group of immune-mediated diseases that mainly affect the skeletal muscles and skin. This case report narrates the story of a middle-aged man who presented with fever, weight loss, muscle weakness and skin rash and was treated elsewhere for probable dermatomyositis with steroids, methotrexate and rituximab. He presented to our facility with persistent fever and hyperpigmented skin rash. Detailed re-evaluation ultimately led to the final diagnosis of haemophagocytic lymphohistiocytosis due to visceral leishmaniasis. He was treated with liposomal amphotericin B. The patient responded well to treatment and did not require further immunosuppression during follow-up. This case highlights the importance of carefully recognising atypical findings to differentiate the IIM from its mimics, particularly infections in endemic areas.