Diagnostic challenge: Bethlem myopathy mimicking inflammatory myopathy.

We describe a young man with persistent hyperCKemia and MRI findings initially suggestive of inflammatory myopathy, in whom genetic testing confirmed Bethlem myopathy. This case illustrates how collagen VI-related myopathies can mimic idiopathic inflammatory myopathies (IIM), underlining the need for integrated clinical, imaging, biopsy, and genetic data to ensure diagnostic accuracy and avoid unnecessary immunosuppression.