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Endocrinology
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Principles of Endocrinology
Overview of the Endocrine System
Hypothalamic-Pituitary Relationships
Hypothalamic Controls
Anterior Pituitary Function
Adrenocorticotropic hormone (ACTH)
Thyroid-stimulating hormone (TSH)
Luteinizing hormone (LH) and follicle-stimulating hormone (FSH)
Growth hormone (GH)
Prolactin
Other hormones
Posterior Pituitary Function
Vasopressin (antidiuretic hormone, ADH)
Oxytocin
Overview of Endocrine Disorders
Endocrine hyperfunction
Endocrine hypofunction
Laboratory Testing for Endocrine Disorders
Blood hormone measurements
Blood hormone estimates
Dynamic tests
Treatment
Aging and Endocrinology
Specific age-related hormone decreases
Specific hormones that remain unchanged during aging
Specific age-related hormone increases
Aging and endocrinology references
Obesity and the Metabolic Syndrome
Obesity
General references
Etiology
Genetic factors
Lifestyle and behavioral factors
Regulatory factors
Eating disorders
Etiology references
Complications
Complications references
Diagnosis
Body composition analysis
Other testing
Diagnosis references
Treatment
Diet
Physical activity
Behavioral interventions
Anti-obesity medications
Surgery
Treatment references
Special Populations
Children
Older adults
Special populations references
Prognosis
Prevention
Key Points
Metabolic and Bariatric Surgery
Reference
Indications
Indications reference
Procedures
Sleeve gastrectomy
Roux-en-Y gastric bypass (RYGB) surgery
Revisional procedures
Biliopancreatic diversion with a duodenal switch (BPD-DS)
Single anastomosis duodeno-ileal bypass with sleeve gastrectomy (SADI-S)
Endoscopic procedures
Adjustable gastric banding
Procedures references
Preoperative Evaluation
Preoperative evaluation reference
Risks
Risks references
Prognosis
Prognosis references
Follow-up
Key Points
Metabolic Syndrome
General reference
Diagnosis
Diagnosis reference
Treatment
Key Points
Adrenal Disorders
Overview of Adrenal Function
Adrenal cortex
Adrenal medulla
Clinical syndromes
Primary Adrenal Insufficiency (Addison Disease)
General reference
Etiology
Etiology reference
Pathophysiology
Mineralocorticoid deficiency
Glucocorticoid deficiency
Symptoms and Signs
Adrenal crisis
Diagnosis
Differential diagnosis
Testing
Provocative testing
Testing for etiology
Diagnosis reference
Treatment
Treatment of adrenal crisis
Treatment of complications
Treatment reference
Key Points
Secondary Adrenal Insufficiency
Symptoms and Signs
Diagnosis
Diagnosis reference
Treatment
Key Points
Adrenal Virilism
Symptoms and Signs
Diagnosis
Treatment
Treatment reference
Key Points
Cushing Syndrome
Etiology
Symptoms and Signs
Diagnosis
Urinary free cortisol measurement
Dexamethasone suppression test
Midnight cortisol measurements
Plasma ACTH measurement
Imaging
Diagnosis references
Treatment
ACTH-secreting pituitary tumors
Glucocorticoid-secreting adrenocortical tumors
Ectopic ACTH-producing tumors
Nelson syndrome
Treatment reference
Key Points
Primary Aldosteronism
General reference
Symptoms and Signs
Diagnosis
Diagnosis reference
Treatment
Treatment reference
Key Points
Secondary Aldosteronism
Symptoms and Signs
Diagnosis
Diagnosis reference
Treatment
Key Points
Pheochromocytoma
General reference
Symptoms and Signs
Symptoms and signs reference
Diagnosis
Blood tests
Urine tests
Other tests
Diagnosis reference
Treatment
Treatment reference
Key Points
Nonfunctional Adrenal Masses
Reference
Symptoms and Signs
Diagnosis
Diagnosis reference
Treatment
Treatment references
Diabetes Mellitus and Hypoglycemia
Overview of Diabetes Mellitus
General references
Types of Diabetes
Type 1 and 2 Diabetes
Other Types and Causes of Diabetes
Diagnosis of Diabetes Mellitus
Diagnosis reference
Complications
Special Populations
Patients with difficulty maintaining goal glucose levels
Children and adolescents
Patients with heart failure
Hospitalized patients
Patients undergoing surgery
Special populations references
Type 2 Diabetes Mellitus
Etiology
Etiology references
Screening and Prevention of Type 2 Diabetes
Screening
Prevention
Screening and prevention references
Symptoms and Signs
Diagnosis
Diagnosis references
Treatment
Diabetes education
Diet
Exercise
Weight loss
Pharmacotherapy
Foot care
Vaccination
Treatment references
Monitoring Type 2 Diabetes Treatment
Monitoring references
Complications
Complications of diabetes in general
Complications specific to type 2 diabetes
Screening for complications in type 2 diabetes
Complications references
Key Points
More Information
Acute Complications of Diabetes Mellitus
Diabetic Ketoacidosis
General references
Pathophysiology
Symptoms and Signs
Diagnosis
Treatment
Prognosis
Key Points
Hyperosmolar Hyperglycemic State (HHS)
General reference
Symptoms and Signs
Diagnosis
Treatment
Key Points
Alcoholic Ketoacidosis
Pathophysiology
Symptoms and Signs
Diagnosis
Treatment
Key Points
Hypoglycemia
Etiology
Well-appearing patients
Ill-appearing patients
Pseudohypoglycemia
Etiology references
Symptoms and Signs
Symptoms and signs references
Diagnosis
Treatment
Treatment in patients taking antihyperglycemic medications
Treatment in patients not taking antihyperglycemic medications
Key Points
Long-Term Complications of Diabetes Mellitus
General reference
Monitoring for Long-Term Complications
Monitoring complications references
Diabetic Retinopathy
Diabetic retinopathy reference
Diabetic Nephropathy
Diabetic nephropathy references
Diabetic Neuropathy
Diabetic foot screening
Diabetic neuropathy reference
Macrovascular Disease
Macrovascular disease references
Heart failure and cardiomyopathy
Heart failure and cardiomyopathy reference
Infection
Infection references
Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD)
MASLD references
Other Complications
Key Points
More Information
Medications for Diabetes Mellitus Treatment
General references
Insulin
Insulin preparations
Insulin regimens for type 1 diabetes
Insulin pumps
Insulin regimens for type 2 diabetes
Complications of insulin treatment
Insulin references
Oral Antihyperglycemic Medications
Sulfonylureas
Short-acting insulin secretagogues
Biguanides
Thiazolidinediones
Alpha-glucosidase inhibitors
Dipeptidyl peptidase-4 inhibitors
Sodium glucose cotransporter 2 inhibitors
Dopamine agonist
Oral antihyperglycemic medications references
Injectable Antihyperglycemic Medications
Glucagon-like peptide-1 (GLP-1) receptor agonists
Dual incretin agonists (glucose-dependent insulinotropic polypeptide [GIP]/ glucagon-like peptide-1 [GLP-1] receptor agonist)
Amylin analog
Injectable antihyperglycemic medications references
Disease-Modifying Medications for Diabetes
Disease-modifying medications references
Adjunctive Medications for Diabetes
Adjunctive medications references
Type 1 Diabetes Mellitus
Etiology
Etiology references
Screening and Prevention of Type 1 Diabetes
Screening
Prevention
Screening and prevention references
Symptoms and Signs
Diagnosis
Diagnosis references
Treatment
Pharmacotherapy
Diabetes education
Diet
Exercise
Foot care
Vaccination
Pancreas and islet cell transplantation
Treatment references
Monitoring Type 1 Diabetes Treatment
Fingerstick glucose monitoring
Continuous glucose monitoring
Hemoglobin A1C
Fructosamine
Urine monitoring
Monitoring references
Complications
Long-term complications
Comorbidities specific to type 1 diabetes
Screening for complications of type 1 diabetes
Complications references
Key Points
More Information
Lipid Disorders
Isolated Elevated High-Density Lipoprotein Cholesterol (HDL-C) Levels
Overview of Lipid Metabolism
Physiology
Exogenous (dietary) lipid metabolism
Endogenous lipid metabolism
References
Dyslipidemia
General references
Classification
Etiology
Primary causes
Secondary causes
Etiology references
Symptoms and Signs
Diagnosis
Lipid profile measurement
Other tests
Secondary causes
Diagnosis references
Screening
Screening in children
Screening in adults
Screening references
Treatment
General principles
Elevated LDL-C treatment
Elevated LDL-C in children
Elevated triglycerides
Low HDL-C
Elevated Lp(a)
Treatment in patients with comorbidities
Monitoring treatment
Treatment references
Key Points
Hypolipidemia
Abetalipoproteinemia (Bassen-Kornzweig syndrome)
Chylomicron retention disease (Anderson disease)
Hypobetalipoproteinemia
Parathyroid Disorders
Overview of Parathyroid Function
Hyperparathyroidism
Etiology
Pathophysiology
Primary hyperparathyroidism
Secondary hyperparathyroidism
Tertiary hyperparathyroidism
Symptoms and Signs
Complications
Diagnosis
Diagnosis reference
Treatment
Medical management
Surgery
Hyperparathyroidism in renal failure
Treatment of severe hyperparathyroidism
Treatment of tertiary hyperparathyroidism
Treatment reference
Key Points
Hypoparathyroidism
Etiology
Postoperative hypoparathyroidism
Idiopathic hypoparathyroidism
Pseudohypoparathyroidism
Symptoms and Signs
Diagnosis
Treatment
Key Points
Parathyroid Tumors
Parathyroid adenoma
Parathyroid cancer
Reference
Key Points
Pituitary Disorders
Introduction to Pituitary Disorders
Pituitary Lesions
Empty sella syndrome
Anterior lobe lesions
Posterior lobe lesions
Reference
Generalized Hypopituitarism
Symptoms and Signs
Diagnosis
Imaging tests
Laboratory testing
Treatment
Treatment reference
Selective Pituitary Hormone Deficiencies
Gigantism and Acromegaly
Symptoms and Signs
Pituitary gigantism
Acromegaly
Diagnosis
Screening for complications
Diagnosis references
Treatment
Surgical therapy
Pharmacotherapy
Radiation therapy
Treatment reference
Prognosis
Key Points
Prolactinoma
Etiology
Symptoms and Signs
Diagnosis
Treatment
Microadenomas
Macroadenomas
Treating pregnant patients
Treatment reference
Key Points
Arginine
Vasopressin
Deficiency (Central Diabetes Insipidus)
Pathophysiology
Etiology
Primary arginine vasopressin deficiency
Secondary arginine vasopressin deficiency
Symptoms and Signs
Diagnosis
Primary polydipsia
Treatment
Hormonal medications
Nonhormonal medications
Key Points
Polyglandular Deficiency Syndromes
Drug-Induced Autoimmunity
References
IPEX Syndrome
General references
Treatment
Treatment references
POEMS Syndrome
Symptoms and Signs
Diagnosis
Treatment
Treatment references
Polyglandular Deficiency Syndromes
Etiology
Pathophysiology
Classification
Type 1 polyglandular deficiency
Type 2 polyglandular deficiency
Type 3 polyglandular deficiency
Classification reference
Symptoms and Signs
Diagnosis
Diagnosis reference
Treatment
Treatment references
Key Points
Thyroid Disorders
Overview of Thyroid Function
Synthesis and Release of Thyroid Hormones
Laboratory Testing of Thyroid Function
Thyroid-stimulating hormone (TSH) measurement
Thyroxine (T4) measurement
Triiodothyronine (T3) measurement
Thyroxine-binding globulin (TBG)
Autoantibodies to thyroid peroxidase
Thyroglobulin
Radioactive Iodine Uptake and Imaging
Screening for Thyroid Disease
Screening for thyroid disease in newborns
Screening for thyroid disease in adults
Screening references
Approach to the Patient With a Thyroid Nodule
General reference
Etiology
Evaluation
History
Physical examination
Laboratory testing
Thyroid imaging
Fine-needle aspiration biopsy
Evaluation references
Treatment
Treatment references
Euthyroid Sick Syndrome
Diagnosis
Treatment
Key Points
Hashimoto Thyroiditis
Symptoms and Signs
Diagnosis
Treatment
Key Points
Hyperthyroidism
General reference
Etiology
Etiology reference
Pathophysiology
Symptoms and Signs
Eye signs
Infiltrative dermopathy
Thyroid storm
Diagnosis
Subclinical hyperthyroidism
Treatment
Radioactive sodium iodine (iodine-131, radioiodine)
Methimazole and propylthiouracil
Beta-blockers
Iodine
Surgery
Treatment of thyroid storm
Treatment of infiltrative dermopathy
Treatment of infiltrative ophthalmopathy
Management of subclinical hyperthyroidism
Treatment references
Key Points
Hypothyroidism
Primary hypothyroidism
Secondary hypothyroidism
Subclinical hypothyroidism
General references
Symptoms and Signs
Myxedema coma
Diagnosis
Screening
Diagnosis references
Treatment
Myxedema coma
Treatment reference
Geriatrics Essentials: Hypothyroidism
Key Points
Silent Lymphocytic Thyroiditis
General reference
Symptoms and Signs
Diagnosis
Treatment
Key Points
Subacute Thyroiditis
Symptoms and Signs
Diagnosis
Treatment
Prognosis
Key Points
Simple Nontoxic Goiter
Symptoms and Signs
Symptoms and signs reference
Diagnosis
Diagnosis reference
Treatment
Key Points
Thyroid Cancers
General references
Papillary Thyroid Carcinoma
Papillary thyroid carcinoma references
Follicular Thyroid Carcinoma
Follicular thyroid carcinoma reference
Oncocytic Thyroid Carcinoma (formerly Hurthle Cell Carcinoma)
Oncotic thyroid carcinoma references
Anaplastic Thyroid Carcinoma
Anaplastic thyroid carcinoma references
Medullary Thyroid Carcinoma
Medullary thyroid carcinoma references
Radiation-Induced Thyroid Cancer
Radiation-induced thyroid cancer references
Male Reproductive Endocrinology and Related Disorders
Anabolic Androgenic Steroids
General references
Pathophysiology
Chronic effects
Pathophysiology references
Symptoms and Signs
Diagnosis
Treatment
Treatment references
Prevention
Male Reproductive Endocrinology
Physiology
Sexual Differentiation, Adrenarche, and Puberty
Effects of Aging
References
Male Hypogonadism
Etiology
Symptoms and Signs
Symptoms and signs reference
Diagnosis
Diagnosis of primary and secondary hypogonadism
Evaluation of secondary hypogonadism
Diagnosis reference
Treatment
Testosterone replacement therapy (TRT)
Treatment of infertility due to hypogonadism
Treatment references
Key Points
Gynecomastia
Pathophysiology
Etiology
Evaluation
History
Physical examination
Red flags
Interpretation of findings
Testing
Treatment
Key Points
