Endocrinology, Diabetes, and Metabolism

Overview

Endocrinology is the diagnosis and care of disorders of the endocrine system. The principal

endocrine problems handled by the general internist include goiter, thyroid nodules, thyroid

dysfunction, diabetes mellitus, hyper- and hypocalcemia, adrenal cortex hyper- and

hypofunction, endocrine hypertension, gonadal disorders, hyper- and hyponatremia, certain

manifestations of pituitary tumors, disorders of mineral metabolism, and hyperlipidemias.

Obesity is not strictly an endocrine disorder but is considered part of the spectrum of

endocrinology because it frequently enters into the differential diagnosis of endocrine disease

and is a major element in the management of non–insulin-dependent diabetes. Prevention efforts

focus on complications of hyperlipidemias, obesity, thyroid dysfunction, and diabetes mellitus,

and on endocrinologic side effects of pharmacologic glucocorticoida and other medications.

The general internist must be able to evaluate and manage common endocrine disorders and refer

appropriately. He or she must also be able to evaluate and identify the endocrinologic

implications of abnormal serum electrolytes, hypertension, fatigue, and other nonspecific

presentations. The general internist plays a key role in managing endocrine emergencies,

particularly those encountered in the intensive care unit, including diabetic ketoacidosis and

hyperosmolar nonketotic stupor, severe hyper- and hypocalcemia, and addisonian crisis.

Common Clinical Presentations

h Asthenia

h Blood lipid disorders

h Breast discharge

h Change in menstrual, gonadal/sexual function

h Diarrhea

h Disorders of pigmentation

h Goiter (diffuse, nodular)

h Hirsutism

h Hypertension refractory to primary therapy

h Hypotension

h Incidentally discovered abnormalities in serum electrolytes, calcium, phosphate, or

glucose

h Mental status changes

h Osteopenia

h Polyuria, polydypsis

h Signs and symptoms of osteopenia

h Symptoms of hyper- and hypoglycemia

h Symptoms of hypermetabolism

h Symptoms of hypometabolism

h Urinary tract stone

h Weight gain, obesity

Procedure Skills

h Dexamethasone suppression test (overnight)

h Home blood glucose monitoring

h ACTH stimulation test

Primary Interpretation of Tests

h None specific to the discipline

Ordering and Understanding Tests

h Bone mineral analysis (densitometry)

h Fasting and standardized postprandial serum glucose concentrations

h Glycohemoglobin or serum fructosamine concentration

h Imaging studies of the sella turcica

h Microalbuminuria

h Serum alkaline phosphatase activity (for Paget’s disease of bone)

h Serum and urine ketone concentrations (quantitative or qualitative)

h Serum and urine osmolalities

h Serum gonadotropin concentrations (follicle-stimulating hormone, luteinizing hormone)

h Serum lipid profile

h Serum phosphate concentration

h Serum prolactin concentration

h Serum testosterone concentration

h Serum thyroid function tests

h Thyroid scanning and ultrasound

h Urinary calcium, phosphate, uric acid excretion

h Urinary sodium, potassium excretion

h Urine metanephrine, VMA (vanillylmandelic acid), and total catecholamine levels