A case of Sjögren's syndrome with renal tubular acidosis complicated with prominant nephrocalcinosis

A 35-year-old woman was admitted, because of xerostomia and a recurrent episode of muscular weakness. Laboratory data showed metabolic acidosis and hypokalemia.Since keratoconjunctivitis and chronic sialoadenitis were also ascertained, a diagnosis of periodic paralysis in Sjögren's syndrome (SjS) secondary to renal tubular acidosis was made. Furthermore, roentgenogram revealed remarkable calcification of bilateral kidneys. Both periodic paralysis and nephrocalcinosis are very rare complications in SjS. However, it might be reasonable to consider that they are the results of the chronic interstitial nephritis as a part of systemic exocrinopathy caused by autoimmune processes in SjS. The metabolic acidosis and hypokalemia gradually improved by the treatment with prednisolone.