Clinical features

The features of Cushing's syndrome are best considered in terms of the physiological effects of glucocortiocoids. Many of the prominent features of severe disease - severe obesity, hypertension, hirsutism and diabetes - are found in non-Cushingoid patients. The most valuable discriminatory features are:

• palpably thin skin with easy bruising and oedema
• proximal myopathy and weakness - difficulty arising from a squatting position may be striking
• growth arrest with obesity in children
• osteoporosis leading to back pain, vertebral collapse, kyphosis, loss of height and rib fractures
• avascular necrosis of the femoral head

Other features:

• weight gain and obesity - distribution is around the trunk and abdomen - buffalo hump - and the face - moon face; supraclavicular fat pads; limbs are relatively thin - "orange on a stick"
• additional skin changes are acne and hirsutism in women, facial plethora and abdominal, breast and thigh striae which are red or purple. Pigmentation suggests elevated ACTH
• hypertension - with associated cardiovascular complications such as ischaemic heart disease
• diabetes - polydyspsia, polyuria; nocturia may occur without elevation in blood glucose
• psychiatric symptoms - depressive psychosis - 20% - to mood lability, insomina and inverted sleep rhythm

Complications associated with elevated cortisol include:

• infection - fungal skin infection and urinary infection
• gonadal dysfunction - impotence in males; oligomenorrhoea in females
• poor wound healing

Weight loss, profound proximal myopathy, pigmentation and hypokalaemic alkalosis suggests ectopic ACTH secretion.