A rare genetic hypoaldosteronism that typically presents in infancy (earl-onset familial hypoaldosternism) as a life-threatening electrolyte imbalance (failure to thrive, recurrent vomiting, and severe dehydration). A history of fever, diarrhoea, lethargy, poor weight gain, poor feeding since birth may also be present. Older subjects (late-onset familial hypoaldosteronism) are less severely affected or asymptomatic.