Match each patient's clinical presentation with the most likely characteristic finding on muscle biopsy.
- A 65-year-old man with insidious, asymmetric grip weakness, frequent tripping, and mild creatine kinase elevation.Endomysial inflammation with rimmed vacuoles containing amyloid-like material
- A 45-year-old woman with progressive symmetric proximal weakness, a violaceous periorbital rash, and marked creatine kinase elevation.Perifascicular atrophy and perimysial inflammation with CD4+ T cells
- A 50-year-old man with symmetric proximal muscle weakness, interstitial lung disease, and no cutaneous manifestations; anti-Jo-1 antibody is positive.Endomysial inflammation with CD8+ T cells invading non-necrotic muscle fibers
- A 55-year-old woman with severe proximal muscle weakness persisting despite statin cessation; anti-HMG-CoA reductase antibodies are positive.Scattered necrotic and regenerating muscle fibers with minimal to absent inflammatory cell infiltrate
Answer
The correct matches align Inclusion Body Myositis with rimmed vacuoles, Dermatomyositis with perifascicular atrophy, Polymyositis with CD8+ T cell endomysial invasion, and Immune-Mediated Necrotizing Myopathy with necrosis lacking significant inflammation.
Each idiopathic inflammatory myopathy possesses distinct clinical and histopathologic features. Dermatomyositis is characterized by humoral-mediated perivascular inflammation resulting in perifascicular atrophy. Polymyositis involves direct T-cell cytotoxicity against muscle fibers, appearing as endomysial CD8+ cells. Inclusion body myositis uniquely presents in older males with asymmetric distal weakness and shows rimmed vacuoles. Immune-mediated necrotizing myopathy features profound myonecrosis with scant inflammation.
Step-by-Step Solution
Key Concept
Clinicopathologic correlation of idiopathic inflammatory myopathies
Estimated Time:2m 0s