Normokalemic Thyrotoxic Periodic Paralysis with Preserved Reflexes- A Unique Case Report

Although serum potassium levels are usually subnormal in Thyrotoxic Periodic Paralysis (TPP), but in exceptionally rare circumstances, it may be normal leading to the entity called normokalemic TPP. The diagnosis of normokalemic TPP is more often overlooked and/or delayed due to lack of awareness among the physicians and associated mild symptoms of hyperthyroidism. Here, the author describes the case of a 27-year-old male with newly diagnosed but untreated Grave's disease and TPP who was normokalemic during the acute phase of paralysis. Hypokalemia was documented only after resolution of paralytic attacks during subsequent days of admission. The importance of the case report is to highlight upon the fact that TPP should always be considered in an "previously asymptomatic" young Asian individual with acute paralysis with or without hypokalemia, and thyroid function and serial potassium values should be evaluated for diagnosing the usual hypokalemic type or the more rarer variant normokalemic TPP. This case report also deserves mention as the patient of TPP had a notable feature of having preserved reflexes in the face of hypokalemia.