Peripheral eosinophilia in amyopathic dermatomyositis: an atypical presentation with diagnostic and therapeutic implications

Amyopathic dermatomyositis (ADM) is a rare variant of dermatomyositis characterised by the pathognomonic cutaneous features of the disease in the absence of clinically significant muscle weakness for at least 6 months. Peripheral eosinophilia is an uncommon laboratory finding associated with ADM and is more commonly linked to allergic, parasitic or haematological disorders.We present the case of a woman in her 70s with classic cutaneous signs of dermatomyositis associated with pruritus for 3 years, preserved muscle strength and persistent peripheral eosinophilia. Secondary causes of eosinophilia were excluded, and a diagnosis of ADM was made based on clinical features and antibody positivity. The patient showed an adequate response to systemic corticosteroids, with resolution of skin lesions and normalisation of eosinophil counts.This case highlights the importance of considering ADM in patients presenting with unexplained eosinophilia and characteristic cutaneous manifestations and adds to the limited literature describing eosinophilic manifestations in inflammatory myopathies.