Primary Sjögren's syndrome presenting as hypokalaemic periodic paralysis and respiratory arrest

We report a case of hypokalaemic, flaccid quadriparesis with sudden respiratory arrest in a 27-year-old Japanese woman in whom the discovery of distal renal tubular acidosis led to the diagnosis of primary Sjögren's syndrome (SS). Hypokalaemic periodic paralysis as the initial manifestation of primary SS is rare, but when it occurs it may precede symptoms of xerostomia and xerophthalmia. The diagnosis of primary SS should be considered in premenopausal women who present with rapidly progressive weakness and hypokalaemia. with or without the sicca complex.