Multiple autoimmune syndrome revealed by nephrogenic diabetes insipidus and hypokalaemic paralysis.

A presentation of postpartum polydipsia and polyuria followed by periodic weakness led to the diagnosis of nephrogenic diabetes insipidus and hypokalaemic paralysis, both of which are complications of primary Sjögren's syndrome (pSS). The clinically dominant pSS was taken to coexist with long-latent systemic lupus erythematosus and asymptomatic autoimmune thyroid disease. This case of multiple autoimmune syndrome is a distinctive subgroup of autoimmune disorders that is increasingly recognized. Female hormone levels appeared to play a role in disease pathogenesis in this case. The patient was predicted to have a favourable prognosis due to the absence of major organ involvement. This case revealed an uncommon form of complex polyautoimmune phenomena and should prompt physicians to extend immunological screening, particularly for females with multiple illnesses.