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Endocrine and Metabolic Disorders
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Endocrine and Metabolic Disorders
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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
Acid-Base Regulation and Disorders
Acid-Base Regulation
Acid-Base Physiology
Acid-Base Balance
Chemical buffering
Pulmonary pH regulation
Renal pH regulation
Acid-Base Disorders
Classification
Symptoms and Signs
Diagnosis
Calculation of the anion gap
Key Points
Metabolic Acidosis
Etiology
High anion gap acidosis
Normal anion gap acidosis
Symptoms and Signs
Diagnosis
Treatment
Key Points
Lactic Acidosis
Type A lactic acidosis
Type B lactic acidosis
D-Lactic acidosis
Symptoms and Signs
Diagnosis
Treatment
Key Points
Metabolic Alkalosis
Etiology
Symptoms and Signs
Diagnosis
Treatment
Key Points
Respiratory Acidosis
Symptoms and Signs
Diagnosis
Treatment
Key Points
Respiratory Alkalosis
Etiology
Pathophysiology
Pseudorespiratory alkalosis
Symptoms and Signs
Diagnosis
Treatment
Key Points
Adrenal Disorders
Overview of Adrenal Function
Adrenal cortex
Adrenal medulla
Clinical syndromes
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
Treatment
Treatment of adrenal crisis
Treatment of complications
Key Points
Secondary Adrenal Insufficiency
Symptoms and Signs
Diagnosis
Treatment
Key Points
Adrenal Virilism
Symptoms and Signs
Diagnosis
Treatment
Key Points
Cushing Syndrome
Etiology
Symptoms and Signs
Diagnosis
Urinary free cortisol measurement
Dexamethasone suppression test
Midnight cortisol measurements
Plasma ACTH measurement
Imaging
Treatment
ACTH-secreting pituitary tumors
Corticosteroid-secreting adrenocortical tumors
Ectopic ACTH-producing tumors
Nelson syndrome
Treatment reference
Key Points
Nonfunctional Adrenal Masses
Reference
Symptoms and Signs
Diagnosis
Treatment
More Information
Pheochromocytoma
General reference
Symptoms and Signs
Symptoms and signs reference
Diagnosis
Blood tests
Urine tests
Other tests
Treatment
Key Points
Primary Aldosteronism
Symptoms and Signs
Diagnosis
Treatment
Treatment references
Key Points
More Information
Secondary Aldosteronism
Symptoms and Signs
Diagnosis
Treatment
Key Points
Amyloidosis
Amyloidosis
Etiology
AL amyloidosis
Hereditary amyloidosis
ATTRwt amyloidosis
AA amyloidosis
Localized amyloidosis
Etiology references
Symptoms and Signs
Diagnosis
Biopsy
Amyloid typing
Organ involvement
Diagnosis references
Treatment
Supportive care
AL amyloidosis
ATTRv (hereditary) amyloidosis
ATTRwt amyloidosis
AA amyloidosis
Treatment references
Prognosis
Prognosis reference
Key Points
Gastrointestinal and Pancreatic Neuroendocrine Tumors (NETs)
Overview of Gastrointestinal and Pancreatic Neuroendocrine Tumors (NETs)
General references
Treatment
Treatment references
Gastrinoma
General reference
Symptoms and Signs
Symptoms and signs reference
Diagnosis
Treatment
Acid suppression
Surgery
Chemotherapy
Treatment references
Prognosis
Prognosis reference
Key Points
Glucagonoma
General reference
Symptoms and Signs
Diagnosis
Treatment
Treatment reference
Insulinoma
General reference
Symptoms and Signs
Diagnosis
Diagnosis reference
Treatment
Treatment reference
Key Points
Vipoma
Symptoms and Signs
Symptoms and signs reference
Diagnosis
Diagnosis reference
Treatment
Treatment reference
Key Points
Gastrointestinal Neuroendocrine Tumors and Carcinoid Syndrome
Etiology
Pathophysiology
Symptoms and Signs
Diagnosis
Tumor localization
Exclusion of other causes of flushing
Treatment
Treatment references
Prognosis
Key Points
Diabetes Mellitus and Disorders of Carbohydrate Metabolism
Diabetes Mellitus (DM)
Complications
Etiology
Type 1 diabetes
Type 2 diabetes
Miscellaneous types of diabetes
Etiology references
Symptoms and Signs
Diagnosis
Monitoring for complications of diabetes
Diagnosis references
Treatment
Overview of pharmacotherapy
Patient education
Diet
Exercise
Weight loss
Foot care
Vaccination
Pancreas transplantation
Treatment references
Monitoring Diabetes Treatment
Fingerstick glucose monitoring
Continuous glucose monitoring
Hemoglobin A1C
Fructosamine
Urine glucose
Monitoring references
Special Populations and Settings
Patients with difficulty maintaining goal glucose levels
Children
Adolescents
Hospitalization
Surgery
Screening
Type 1 diabetes
Type 2 diabetes
Screening reference
Prevention
Type 1 diabetes
Type 2 diabetes
Complications
Prevention references
Key Points
More Information
Complications of Diabetes Mellitus
Diabetic Retinopathy
Diabetic Nephropathy
Diabetic nephropathy references
Diabetic Neuropathy
Macrovascular Disease
Macrovascular disease references
Cardiomyopathy
Infection
Infection references
Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD)
MASLD references
Other Complications
More Information
Medications for Diabetes Mellitus Treatment
Insulin
Insulin preparations
Insulin pumps
Complications of insulin treatment
Insulin regimens for type 1 diabetes
Insulin regimens for type 2 diabetes
Insulin references
Oral Antihyperglycemic Medications
Sulfonylureas
Short-acting insulin secretagogues
Biguanides
Thiazolidinediones
Alpha-glucosidase inhibitors
Dipeptidyl peptidase-4 inhibitors
Sodium-glucose co-transporter 2 inhibitors
Dopamine agonist
Oral antihyperglycemic medications reference
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
Disease-Modifying Medications for Diabetes
Disease-modifying medications references
Adjunctive Medications for Diabetes
Adjunctive medications references
More Information
Diabetic Ketoacidosis (DKA)
Pathophysiology
Symptoms and Signs
Diagnosis
Diagnosis references
Treatment
Volume repletion
Correction of hyperglycemia and acidosis
Hypokalemia prevention
Other measures
Treatment references
Prognosis
Prognosis references
Key Points
Hyperosmolar Hyperglycemic State (HHS)
Symptoms and Signs
Diagnosis
Treatment
Treatment references
Key Points
Alcoholic Ketoacidosis
Pathophysiology
Symptoms and Signs
Diagnosis
Treatment
Key Points
Hypoglycemia
Etiology
Symptoms and Signs
Symptoms and signs references
Diagnosis
Treatment
Treatment in patients taking antihyperglycemic medications
Treatment in patients not taking antihyperglycemic medications
Key Points
Electrolyte Disorders
Hypernatremia
Etiology
Hypovolemic hypernatremia
Euvolemic hypernatremia
Hypervolemic hypernatremia
Hypernatremia in older adults
Symptoms and Signs
Diagnosis
Treatment
Key Points
Hyponatremia
Etiology
Hypovolemic hyponatremia
Euvolemic hyponatremia
Hypervolemic hyponatremia
Syndrome of inappropriate antidiuretic hormone secretion (SIADH)
Hyponatremia in AIDS
Cerebral salt wasting (CSW)
Symptoms and Signs
Diagnosis
Exclusion of translocational hyponatremia and pseudohyponatremia
Identification of the cause
Treatment
Mild to moderate hyponatremia
Severe hyponatremia
Rapid-onset hyponatremia
Hypertonic saline solution
Selective vasopressin receptor antagonists
Chronic hyponatremia
Osmotic demyelination syndrome
Key Points
Overview of Disorders of Potassium Concentration
Potassium shifts
Potassium metabolism
Pseudohypokalemia and pseudohyperkalemia
Hyperkalemia
Etiology
Symptoms and Signs
Diagnosis
ECG
Diagnosis of cause
Treatment
Mild hyperkalemia
Moderate to severe hyperkalemia
Key Points
Hypokalemia
Etiology
Gastrointestinal tract losses
Intracellular shift
Renal potassium losses
Medications
Symptoms and Signs
Diagnosis
ECG
Diagnosis of cause
Treatment
Prevention
Key Points
Overview of Disorders of Calcium Concentration
Regulation of Calcium Metabolism
Parathyroid hormone
Calcitonin
Hypercalcemia
Etiology
Pathophysiology
Primary hyperparathyroidism
Familial hypocalciuric hypercalcemia
Secondary hyperparathyroidism
Tertiary hyperparathyroidism
Cancer
Vitamin D toxicity
Granulomatous disorders
Immobilization
Idiopathic infantile hypercalcemia
Milk-alkali syndrome
Symptoms and Signs
Diagnosis
Initial evaluation
Hyperparathyroidism
Cancer
Familial hypocalciuric hypercalcemia (FHH)
Milk-alkali syndrome
Other causes
Treatment
Mild hypercalcemia
Moderate hypercalcemia
Severe hypercalcemia
Hypercalcemia of malignancy
Hyperparathyroidism
Familial hypocalciuric hypercalcemia
Treatment reference
Key Points
Hypocalcemia
Etiology
Hypoparathyroidism
Pseudohypoparathyroidism
Vitamin D deficiency and dependency
Renal disease
Other causes
Symptoms and Signs
Neurologic manifestations
Other manifestations
Diagnosis
Estimation of ionized calcium concentration
Treatment
Tetany
Transient hypoparathyroidism
Chronic hypocalcemia
Key Points
Overview of Disorders of Magnesium Concentration
Hypermagnesemia
Diagnosis
Treatment
Hypomagnesemia
Etiology
Symptoms and Signs
Diagnosis
Treatment
Key Points
Overview of Disorders of Phosphate Concentration
Hyperphosphatemia
Etiology
Pathophysiology
Symptoms and Signs
Diagnosis
Treatment
Key Points
Hypophosphatemia
Etiology
Symptoms and Signs
Diagnosis
Treatment
Oral treatment
Parenteral treatment
Key Points
Syndrome of Inappropriate ADH Secretion (SIADH)
Pathophysiology
Etiology
Medications and SIADH
Etiology reference
Symptoms and Signs
Diagnosis
Treatment
Key Points
Fluid Metabolism
Water and Sodium Balance
Osmotic forces
Water intake and excretion
Overview of Disorders of Fluid Volume
Renin-angiotensin-aldosterone axis
Other natriuretic factors
Sodium depletion and excess
Volume Depletion
Symptoms and Signs
Diagnosis
Treatment
Treatment references
Volume Overload
Symptoms and Signs
Diagnosis
Treatment
Lipid Disorders
Overview of Lipid Metabolism
Physiology
Exogenous (dietary) lipid metabolism
Endogenous lipid metabolism
Dyslipidemia
Classification
Etiology
Primary causes
Secondary causes
Symptoms and Signs
Diagnosis
Lipid profile measurement
Other tests
Secondary causes
Diagnosis reference
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
Elevated High-Density Lipoprotein Cholesterol (HDL-C) Levels
Hypolipidemia
Abetalipoproteinemia (Bassen-Kornzweig syndrome)
Chylomicron retention disease (Anderson disease)
Hypobetalipoproteinemia
Multiple Endocrine Neoplasia (MEN) Syndromes
Overview of Multiple Endocrine Neoplasias (MEN)
Multiple Endocrine Neoplasia, Type 1 (MEN 1)
General references
Symptoms and Signs
Parathyroid
Pancreas
Pituitary
Other manifestations
Symptoms references
Diagnosis
Genetic screening
Diagnosis references
Treatment
Treatment references
Key Points
Multiple Endocrine Neoplasia, Type 2A (MEN 2A)
Symptoms and Signs
Thyroid
Adrenal
Parathyroid
Other manifestations
Diagnosis
Genetic screening
Diagnosis references
Treatment
Treatment references
Key Points
More Information
Multiple Endocrine Neoplasia, Type 2B (MEN 2B)
Symptoms and Signs
Diagnosis
Treatment
Key Points
Multiple Endocrine Neoplasia, Type 4 (MEN 4)
Symptoms and Signs
Symptoms and signs reference
Diagnosis
Treatment
Key Points
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
Arginine
Vasopressin
Deficiency (Central Diabetes Insipidus)
Pathophysiology
Etiology
Primary argininevasopressin deficiency
Secondary argininevasopressin deficiency
Symptoms and Signs
Diagnosis
Primary polydipsia
Treatment
Hormonal medications
Nonhormonal medications
Key Points
More Information
Prolactinoma
Etiology
Symptoms and Signs
Diagnosis
Treatment
Microadenomas
Macroadenomas
Treating pregnant patients
Treatment reference
Key Points
More Information
Generalized Hypopituitarism
Symptoms and Signs
Diagnosis
Imaging tests
Laboratory testing
Treatment
Gigantism and Acromegaly
Symptoms and Signs
Pituitary gigantism
Acromegaly
Diagnosis
Treatment
Surgical therapy
Medical therapy
Radiation therapy
Key Points
Pituitary Lesions
Empty sella syndrome
Anterior lobe lesions
Posterior lobe lesions
Selective Pituitary Hormone Deficiencies
Polyglandular Deficiency Syndromes
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
Drug-Induced Autoimmunity
References
IPEX Syndrome
General references
Treatment
Treatment references
POEMS Syndrome
Symptoms and Signs
Diagnosis
Treatment
Treatment references
The Porphyrias
Overview of Porphyrias
Etiology
Etiology references
Pathophysiology
Diagnosis
Secondary Porphyrinuria
Secondary porphyrinuria references
Acute Porphyrias
Precipitating Factors
Symptoms and Signs
The acute porphyric attack
Subacute and chronic symptoms
Skin symptoms in variegate porphyria and hereditary coproporphyria
Late complications of acute porphyrias
Symptoms and signs references
Diagnosis
Acute attack
Determination of acute porphyria type
Family studies in acute porphyrias
Diagnosis references
Treatment
Recurrent attacks
Treatment references
Prognosis
Prevention
Recurrent or predictable attacks
Prevention references
Key Points
More Information
Overview of Cutaneous Porphyrias
Porphyria Cutanea Tarda
Pathophysiology
Pseudoporphyria
Pathophysiology references
Symptoms and Signs
Diagnosis
Diagnosis references
Treatment
Treatment references
Prevention
Key Points
More Information
Erythropoietic Protoporphyria and X-linked Protoporphyria
Etiology
Etiology references
Symptoms and Signs
Symptoms and signs reference
Diagnosis
Treatment
Treatment references
Key Points
More Information
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
Screening for Thyroid Dysfunction
Screening references
Radioactive Iodine Uptake and Imaging
Hyperthyroidism
General reference
Etiology
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
Subacute Thyroiditis
Symptoms and Signs
Diagnosis
Treatment
Prognosis
Key Points
Silent Lymphocytic Thyroiditis
Symptoms and Signs
Diagnosis
Treatment
Key Points
Hypothyroidism
Primary hypothyroidism
Secondary hypothyroidism
Subclinical hypothyroidism
General reference
Symptoms and Signs
Myxedema coma
Diagnosis
Screening
Treatment
Myxedema coma
Treatment reference
Geriatrics Essentials: Hypothyroidism
Key Points
Hashimoto Thyroiditis
Symptoms and Signs
Diagnosis
Treatment
Key Points
Euthyroid Sick Syndrome
Diagnosis
Treatment
Key Points
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 reference
Simple Nontoxic Goiter
Symptoms and Signs
Symptoms and signs reference
Diagnosis
Treatment
Key Points
Thyroid Cancers
General references
Papillary Thyroid Carcinoma
Papillary thyroid carcinoma references
Follicular Thyroid Carcinoma
Oncocytic Thyroid Carcinoma (formerly Hurthle Cell Carcinoma)
Oncotic thyroid carcinoma references
Anaplastic Thyroid Carcinoma
Anaplastic thyroid carcinoma references
Medullary Thyroid Carcinoma
Medullary thyroid carcinoma reference
Radiation-Induced Thyroid Cancer
Radiation-induced thyroid cancer reference
