A 46-year-old woman presents with 3 months of progressive proximal muscle weakness affecting stair climbing and hair combing. Vital signs: BP 128/82, HR 92, RR 16, Temp 37°C, SpO2 98%. Physical examination reveals no skin rash. Serum creatine kinase is markedly elevated at 3,200 U/L. Electromyography shows myopathic pattern. Muscle biopsy is most likely to show which of the following findings?

  1. A)Neurogenic grouped atrophy from denervation
  2. B)Dystrophin deficiency in muscle fibers
  3. C)Amyloid deposition in endoneurial tissue
  4. D)Endomysial inflammation with CD8 positive T cellsGABARITO
  5. E)Perimysial inflammation with perifascicular atrophy

Explicação

Polymyositis is an inflammatory myopathy characterized by proximal muscle weakness, elevated CK, and endomysial inflammation driven largely by CD8 positive cytotoxic T cells. Lack of rash helps distinguish it from dermatomyositis. Ver explicação completa e trilha adaptativa →

Fazer o diagnóstico grátis de USMLE