Differential diagnosis of Cushing's syndrome

High serum cortisol may occur in alcoholics beside other clinical manifestations that are found in both conditions.

High serum cortisol is also seen in depressed patients.

Elevated serum ACTH, increased urine free cortisol, and increased serum cortisol levels may be found normally in pregnancy.

High serum cortisol is common in the critically ill patients as well.

Increased urinary free cortisol  is seen in anorexia nervosa, which may be confused with Cushing's syndrome, as in both conditions there is muscle wasting, although fat redistribution is characteristic of Cushing's syndrome.

Some clinical features of Cushing's syndrome can be found in normal people.

Abdominal or back striae can be normal in adolescents.

In HIV infected patients, fat distribution with central obesity and thin limbs, is a side effect of anti-retroviral therapy.

Rarely, typical central obesity, a round or moon facies ,and atrophy of the subcutaneous fat in the extremities, are seen in familial  partial lipodystrophy type I. However, in the latter, there is muscle hypertrophy instead of muscle wasting.