Etiological Search and Epidemiological Profile in Patients Presenting with Hypokalemic Paresis: An Observational Study.

INTRODUCTION

Hypokalemia is associated with increased morbidity and at times mortality. "Hypokalemic paralysis", particularly if recurrent, has often been considered synonymous with "hypokalemic periodic paralysis (HPP)"; however, diseases such as Gitelman syndrome (GS), Bartter syndrome (BS), and renal tubular acidosis (RTA) can have identical presentation. We have tried to explore the etiological spectrum along with epidemiological and certain clinical, biochemical, and electrophysiological features in patients with hypokalemic paralysis.

MATERIALS AND

METHODS

In this observational study, 200 appropriate patients with hypokalemic paralysis (serum K+ <3.5 mmol/L) were evaluated for transcellular shift, extra-renal or renal loss of K+ as the underlying etiology of hypokalemia. We took urinary potassium >25 mmol/day as the cutoff for inappropriate renal loss of potassium in presence of hypokalemia. Serum and urinary osmolality along with arterial blood gas analysis were performed in all patients with renal loss of potassium. Serum and urinary sodium, potassium, calcium, magnesium, chloride, and creatinine were measured in normotensive patients with metabolic alkalosis. Hypertensive patients were evaluated with plasma aldosterone and renin activity.

RESULTS

Probable GS topped the list involving 28% individuals of the entire cohort while probable BS, distal RTA, and HPP were diagnosed in 20%, 22%, and 19% cases, respectively. Rural tribal population (61%) and age group of 30-40 years suffered the most (48%) with concentration of cases in hot and humid summer months.

CONCLUSIONS

We suggest that patients with hypokalemic paresis should be evaluated thoroughly to unmask the underlying etiology that may have a different therapeutic and prognostic connotations and not to use the term "periodic" in cases of recurrent hypokalemic paralysis.