Anti-fibrillarin Positive Systemic Sclerosis Presenting With Myositis and Perimyocarditis

A 45-year-old man with no significant past medical history presented with six months of progressive proximal muscle weakness, inflammatory arthralgia, and functional decline, on a background of two years of progressive depigmented pruritic skin lesions. Examination demonstrated widespread hypopigmented sclerotic skin changes, sclerodactyly, and digital ulceration. Investigations revealed mildly elevated creatine kinase (CK) and cardiac biomarkers, with cardiac magnetic resonance imaging (MRI) demonstrating perimyocarditis and thigh MRI showing symmetrical muscle oedema consistent with inflammatory myopathy. Skin biopsy demonstrated dermal fibrosis while serology was positive for anti-fibrillarin antibodies. A diagnosis of anti-fibrillarin-positive systemic sclerosis with inflammatory myositis was made. Treatment with low-dose prednisolone and colchicine resulted in clinical improvement, with mycophenolate mofetil (MMF) planned as a steroid-sparing agent. Initiation was delayed following a positive QuantiFERON-TB (QIAGEN GmbH, Hilden, Germany) test requiring management of latent tuberculosis (TB). This case highlights the diagnostic complexity of anti-fibrillarin-positive systemic sclerosis presenting with simultaneous muscular and cardiac involvement and emphasises the importance of early recognition of multisystem disease.