A 63-year-old man presents with a 3-month history of difficulty rising from a chair and dry mouth. Vital signs: BP 142/88 mmHg, HR 88/min, RR 16/min, temp 37°C, SpO2 98% on room air. Strength improves with repeated muscle activation. Deep tendon reflexes are decreased throughout. Serum creatine kinase is mildly elevated at 450 U/L. Sensory examination is intact. He denies recent medications. Which of the following is the most likely diagnosis?
- A)Multiple sclerosis
- B)Botulism
- C)Lambert-Eaton myasthenic syndromeGABARITO
- D)Polymyositis
- E)Myasthenia gravis
Explicação
Lambert-Eaton syndrome causes proximal weakness, autonomic symptoms such as dry mouth, and depressed reflexes that may improve after exercise. It is due to autoantibodies against presynaptic voltage gated calcium channels, which reduce acetylcholine release. Ver explicação completa e trilha adaptativa →