Paralytic myopathy--a leading clinical presentation for primary aldosteronism in Taiwan

Between 1982 and 1995, 43 cases of primary aldosteronism, 36 cases of adenoma, and 7 cases of hyperplasia were treated in Chang Gung Medical Center. Twenty-one of these (49%) presented with muscular paralysis as an initial symptom (categorized as the paralytic group). Seven patients in the paralytic group (33%) had extralimb muscle involvement. Six of them presented with bulbar palsy and one patient had a peripheral-type facial palsy. The serum potassium levels in the paralytic group were significantly lower than those of the nonparalytic group (1.8 +/- 0.3 vs. 2.3 +/- 0.4 mmol/L, P = 0.0001). There were no significant differences in blood pressure or the serum aldosterone level between the two groups. Provocative factors such as a high carbohydrate diet, vigorous exercise, or seasonal variation did not appear to play a significant role in inducing the symptoms. Paralytic myopathy appears to be more common in Oriental people. The symptom is rarely reported among western populations. Primary aldosteronism should be considered in patients presenting with neuromuscular weakness associated with hypokalemia, regardless of the degree of hypertension.