• Anorexia nervosa (hypogonadotropic hypogonadism)
• Serious illness (hypogonadotropic hypogonadism, functional suppression of TSH & thyroxine)
• Severe malnutrition (hypogonadotropic hypogonadism)
• Hypothyroidism
• Addison’s disease
• High-dose glucocorticoids (secondary adrenal insufficiency for months)
• Cachexia due to other causes (eg, carcinoma, tuberculosis)
• Empty sella syndrome

• Hyperprolactinemia
• Adrenal insufficiency
• Oligomenorrhea & amenorrhea
• Male hypogonadism
• Hypothyroidism

Mass lesions

• Pituitary adenoma (prolactinoma, nonfunctioning, growth hormone-secreting)
• Granuloma
• Brain tumor (eg, craniopharyngioma, meningioma, germinoma, glioma, chondrosarcoma, chordoma of the clivus)
• Rathke’s cleft cyst
• Aneurysm
• Pituitary apoplexy (hemorrhage in pituitary tumor)
• Metastatic carcinoma

Without mass lesion

• Idiopathic
• Trauma
• Cranial irradiation
• Hemochromatosis
• Sarcoidosis
• Surgery
• Encephalitis
• Autoimmune
• Stroke
• Status post-coronary artery bypass graft
• Postpartum pituitary necrosis (Sheehan’s syndrome)
• Langerhans cell histiocytosis
• Eclampsia-preeclampsia
• Sickle cell disease
• African trypanosomiasis