Paraneoplastic Dermatomyositis Due to Gallbladder Carcinoma

Dermatomyositis is an inflammatory myopathy that can be sporadic or paraneoplastic. A 72-year-old female presented with a subacute progressive illness characterized by symmetrical proximal weakness of upper and lower limbs, dysphagia, and neck flexor weakness. On examination, she had erythematous, scaly lesions over the periorbital areas, face, and interphalangeal and metacarpophalangeal joints (Gottron's papules). Neurological examination revealed bilateral palatal palsy, proximal predominant upper and lower limb and neck flexor weakness, areflexia with preserved knee jerks, waddling gait, and normal sensory modalities. Investigations showed polymorphonuclear leukocytosis and elevated creatine kinase. Electromyogram revealed short-duration, small-amplitude polyphasic potentials with fibrillations and positive sharp waves consistent with inflammatory myopathy. Antinuclear antibodies and myositis antibodies were negative. Contrast-enhanced CT revealed a polypoidal lesion in the gallbladder with liver metastasis. She declined a biopsy and was started on prednisolone with minimal improvement. The patient expired one month later.