A 12-year-old female suffering from adrenocortical insufficiency showed symptoms similar to a gastro-enteritis, and severe electrolytic and acid/base disturbances which progressed into cerebral oedema and death. Autopsy findings included depletion of the adrenal cortex, with enlargement and eosinophilia of surviving cells. In ante-mortem blood, anti-adrenal auto-antibodies were found and elevated levels of ACTH and cortisol with a low level of aldosterone.