This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
[{'content': 'In which of the following patients, thyrotoxicosis should not be suspected - \nSelect and explain. \nA. Patients with unexplained weight loss, B. Patients with unexplained diarrhoea, C. Patients with distal muscle weakness, D. Patients with paroxysmal atrial tachycardia', 'role': 'user'}, {'content': 'Answer: C \nExplanation: In hyperthyroidism there is proximal muscle weakness.\xa0\n\nThyrotoxicosis (Hyperthyroidism)\n\nMost common\xa0cause of thyrotoxicosis is diffuse hyperplasia of the thyroid, i.e., Graves disease.\xa0\n\nClinical features\n\nHyperthyroidism is a hypermetabolic state.\nThe effects are due to increased level of thyroxin as well as due to overactivity of the sympathetic nervous system.\n\nFeatures are :\n\nMetabolism\xa0→\xa0↑ BMR, Intolerance to heat, weight loss, increased sweating, postprandial hyperglycemia, ↓cholesterol, ↓ phospholipid, ↓ triglyceride, ↑ FFA, Increased appetite.\nCVS\xa0→\xa0↑ Systolic BP, Hyperdynamic precordium, wide pulse pressure, sinus tachycardia, mid-systolic murmur, Means Lerman scratch, atrial fibrillation, Angina & CHF.\nRespiration\xa0→ ↑ Respiratory rate.\nGIT\xa0→ Diarrhoea\nCNS\xa0→ Nervousness, anxiety\nMusculoskeletal system\xa0→\xa0Proximal muscle weakness, fine tremors, osteoporosis.\nOthers\xa0→ Extreme fatiguability but inability to sleep, infertility.\n\n\nIn Graves disease there is exophthalmos, and wide-eyed, Staring gaze.', 'role': 'assistant'}]