Brittle Addison's disease: a new variation on a familiar theme.

Unstable and unpredictable disease control in diabetes or asthma, with frequent hospitalisations, is frequently referred to as 'brittle'. We describe two cases of Addison's disease with recurrent hospitalisations in hypo-adrenal crises. Both patients had significant psychosocial disruption, and failure to take hydrocortisone replacement therapy was admitted in one and biochemically proven in the other. We propose that 'brittle' Addison's disease in these cases was due to poor treatment compliance related to psychosocial factors. These features have particular similarities with the syndrome of brittle diabetes.