An unusual cause of muscle weakness: a diagnostic challenge for clinicians.

The authors describe a 27-year-old male who presented with acute flaccid quadriparesis. The patient denied any history of similar episodes in the past. At presentation, the patient was tachycardiac with normal systolic blood pressure. He had marked flaccid weakness of both upper and lower limbs and furthermore, he was hypotonic and without tendon reflexes. Biochemical analyses revealed severe hypokalaemia (1.9 meq/l). The patient was given potassium supplementation. He showed complete recovery after the medical intervention. Successive investigations documented an undiagnosed case of Graves' disease. Hypokalaemia secondary to thyrotoxicosis was diagnosed as the cause of the paralysis. Thyrotoxic periodic paralysis is a rare neurologic manifestation of thyrotoxicosis. Absence of obvious signs of thyrotoxicosis poses a diagnostic challenge for the clinicians.