Endocrine Abstracts

A 67 yr old lady was admitted with left ventricular failure, angina, and atrial fibrillation. She was hypokalaemic (2.5mmol/l). There was a 3 year history of hypertension and a new diagnosis of diabetes mellitus. There was a recent history of weight gain, muscle weakness, bruising and facial puffiness. On examination she appeared cushingoid. A 24 hour urine for free cortisol was 1438nmol\/24h (normal<350). A basal 0800h serum cortisol was 1061nmol/l. After low dose dexamethasone (0.5mg 6 hourly for 48h), serum cortisol had not suppressed (823nmol/l). A basal ACTH value was 56 ng/l. After high dose dexamethasone (2mg 6 hourly for 48h, there was suppression by 50% of the basal value to 252nmol/l. There was no significant rise in either serum cortisol or ACTH after intravenous CRH.

CT scan of pituitary was normal. CT scan of chest and abdomen recorded no ectopic source of ACTH. The patient then developed pyrexia and a leucocytosis. Blood cultures were negative. An ultrasound of the liver revealed a 6cm mass in the right lobe. Aspiration biopsy revealed purulent material, which on culture was shown to contain coliforms and mixed anaerobes. She was treated with intravenous antibiotics, and was immediately started on a block and replacement regime for her hypercortisolism. Metyrapone was rapidly increased to a dose of 500mg four times daily and dexamethasone 500mcg daily was given to prevent hypoadrenalism. Serum cortisol values fell rapidly to 67nmol/l. The patient made a full recovery and additional investigations and definitive management is being planned.

In previous descriptions of infections in Cushing's Syndrome, hypercortisolism is often extreme and as in our patient, initial signs and symptoms are often masked by hypercortisolism. Mortality is high, and as in the present case a key prognostic feature is the early reduction of cortisol production to near normal.