Hypokalaemic periodic paralysis in rural northern India--most have secondary causes.

Hypokalaemic periodic paralysis (HPP) is a life-threatening condition. Our aim was to study the clinical profile and laboratory parameters of HPP patients and to develop an algorithm to determine the causes of HPP. 84 patients presented with HPP over a 3 year period. 58 (69.0%) were found to have renal tubular acidosis (RTA). The other causes were idiopathic HPP (8 (9.5%)), acute gastroenteritis (4 (4.8%)), suspected primary hyperaldosteronism and familial HPP (2 each (2.4%)) and suspected Gitelman/Bartter Syndrome and thyrotoxic periodic paralysis (1 each (1.2%)). The number of cases peaks in the hot season. Over a third of the patients (35.7%) had recurrent episodes. 80% had secondary HPP and therefore a biochemical evaluation is mandatory. A simple algorithm was developed. Both health professionals and patients need further education regarding this problem in order to improve diagnosis and treatment and to improve compliance.