Last week (BMJ 2009;338 doi:10.1136/bmj.b6) we presented the case of a 38 year old woman who collapsed from hypotensive shock triggered by the onset of menstruation and which responded to a steroid bolus. She was admitted to the internal medicine department with suspected adrenal insufficiency. At the time of the admission she was stable. She had been well until six months before, when she had presented with a similar but less serious syncopal episode coinciding with abdominal pain and menstruation which resolved with fluid replacement. She reported some episodes of diarrhoea together with short episodes of purple-red discolouration of the neck and face, …