II. Causes

  1. Malignancy (e.g. Bronchogenic Carcinoma)
  2. Lung disease
    1. Pneumonia
    2. Empyema
    3. Legionella pneumonia
  3. Neurologic disorders (Tumors or Meningitis)
  4. Psychiatric illness
  5. Post-operative period
  6. Medications
    1. Chemotherapy
    2. Amiodarone
    3. Carbamazepine (Tegretol)
    4. Chlorpromazine (Thorazine)
    5. Theophylline
    6. Selective Serotonin Reuptake Inhibitors
  7. Multiple Sclerosis
  8. Guillain-Barre Syndrome

III. Differential Diagnosis

  1. SIADH is a diagnosis of exclusion
  2. Isovolemic Hypoosmolar Hyponatremia
  3. Non-osmotic causes for ADH secretion
    1. Hypovolemic Hypoosmolar Hyponatremia
  4. Causes of Decreased urine diluting capacity

IV. Labs

  1. Hyponatremia
    1. See Isovolemic Hypoosmolar Hyponatremia
  2. Urine Osmolality > 100 mOsm/kg water
    1. Dilution not maximized despite serum hypoosmolality
  3. Urine Sodium > 20-30 mEq/L
  4. Serum Osmolality decreased <280 mOsm
  5. Hypouricemia (Serum Uric Acid <4 mg/dl)
  6. Antidiuretic Hormone (ADH) elevated

V. Management

  1. Treating underlying cause is key in SIADH
    1. Example: Treat underlying Bronchogenic Carcinoma
  2. See Isovolemic Hypoosmolar Hyponatremia
    1. Fluid restriction (<1000 ml/day)
    2. Furosemide
    3. Slow Serum Sodium correction
      1. See Hyponatremia Management
  3. SIADH refractory to above measures
    1. Induce Nephrogenic Diabetes Insipidus
    2. Demeclocycline (600-1200 mg/day)
    3. Lithium Carbonate 300 mg PO tid

VI. References

  1. Kone in Tisher (1993) Nephrology, p. 87-100
  2. Levinsky in Wilson (1991) Harrison's IM, p. 281-84
  3. Rose (1989) Acid-Base and Electrolytes, p. 601-38
  4. Goh (2004) Am Fam Physician 69:2387-94

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Ontology: Inappropriate ADH Syndrome (C0021141)

Definition (MSH) A condition of HYPONATREMIA and renal salt loss attributed to overexpansion of BODY FLUIDS resulting from sustained release of ANTIDIURETIC HORMONES which stimulates renal resorption of water. It is characterized by normal KIDNEY function, high urine OSMOLALITY, low serum osmolality, and neurological dysfunction. Etiologies include ADH-producing neoplasms, injuries or diseases involving the HYPOTHALAMUS, the PITUITARY GLAND, and the LUNG. This syndrome can also be drug-induced.
Definition (NCI) A syndrome characterized by abnormal secretion of antidiuretic hormone in conjunction with neoplastic growth occurring anywhere in the body.
Concepts Pathologic Function (T046)
MSH D007177
ICD10 E22.2
SnomedCT 389983008, 55004003
English Inappropriate anti-diuretic hormone syndrome, ADH Syndrome, Inappropriate, Antidiuretic Hormone, Inappropriate Secretion, Inappropriate ADH Syndrome, Schwartz Bartter Syndrome, Schwartz-Bartter Syndrome, SIADH, Syndrome, Inappropriate ADH, Syndrome, Schwartz-Bartter, INAPPROPRIATE SECRETION OF ANTIDIURETIC HORMONE, ADH INAPPROPRIATE, ADH INAPPROPRIATE SECRETION, INAPPROPRIATE ADH, Inappropriate ADH syndrome, SCHWARTZ-BARTTER SYNDROME, SYNDROME INAPPROPRIATE ADH, SYNDROME OF INAPP ADH SECRETION, SYNDROME OF INAPPROPRIATE ANTIDIURETIC HORMONE, Inappropriate ADH, SIAD - Syn inappr antidiuresis, SIADH - Synd inappr secret ADH, SIADH - Syndrome of inappropriate secretion of ADH, Syndrome inappr secretion ADH, Syndrome inapprop antidiuresis, ANTIDIURETIC HORMONE INAPPROPRIATE SECRETION SYNDROME <SIADH>, Syndrome of inappropriate antidiuretic hormone (SIADH), SYNDROME INAPPROPRIATE ADH SIADH SECRET, ANTIDIURETIC HORMONE INAPPROPRIATE SECRET, INAPPROPRIATE VASOPRESSIN SECRET SYNDROME, Syndrome of Inappropriate Antidiuretic Hormone Secretion, Inappropriate Antidiuretic Hormone Secretion Syndrome, inappropriate ADH secretion, Syndrome of inappropriate secretion of antidiuretic hormone (disorder), syndrome of inappropriate secretion of antidiuretic hormone (diagnosis), syndrome of inappropriate secretion of antidiuretic hormone, inappropriate ADH syndrome (SIADH), SIADH (syndrome of inappropriate antidiuretic hormone), Syndrome of inapp ADH secretion, Inapprop. ADH secretion syndrome, ADH inappropriate, ADH inappropriate secretion, Inappropriate ADH secretion, Syndrome inappropriate ADH, Inappropriate vasopressin secretion, SYNDROME INAPPROPRIATE ANTI DIURETIC HORMONE, ANTIDIURETIC HORMONE INAPPROPRIATE SECRETION SYNDROME SIADH, Syndrome of Inappropriate ADH (SIADH) Secretion, Inappropriate Vasopressin Secretion Syndrome, Inappropriate ADH Syndrome [Disease/Finding], adh inappropriate syndrome, adh inappropriate secretion, inappropriate adh, siadhs, siadh, adh inappropriate syndromes, inappropriate adh secretion, Inappropriate antidiuretic hormone secretion, Schwartz-Bartter syndrome, Syndrome of inappropriate ADH production, Syndrome of inappropriate vasopressin secretion, SIAD - Syndrome of inappropriate antidiuresis, SIADH - Syndrome of inappropriate secretion of antidiuretic hormone, Syndrome of inappropriate antidiuresis, Syndrome of inappropriate secretion of antidiuretic hormone, Syndrome of inappropriate vasopressin secretion (disorder), SIADH; (syndrome of inappropriate secretion of antidiuretic hormone), hormone secretion; antidiuretic, inadequate (syndrome), hormone; secretion, antidiuretic, inappropriate (syndrome), inadequate; secretion antidiuretic hormone (syndrome), inappropriate secretion of antidiuretic hormone; syndrome, secretion; hormone, antidiuretic, inappropriate (syndrome), syndrome; inappropriate secretion of antidiuretic hormone, antidiuretic; hormone syndrome (SIADH), antidiuretic; hormone, inappropriate secretion (SIADH), Schwarz-Bartter syndrome, Syndrome of inappropriate secretion of ADH
Italian Secrezione inappropriata di ormone antidiuretico, Ormone antidiuretico inappropriato, Secrezione inappropriata di vasopressina, Inappropriata secrezione di ormone antidiuretico, Sindrome da inappropriata secrezione di ADH, Secrezione inappropriata di ADH, Sindrome da inappropriata secrezione di ormone antidiuretico, Sindome da inappropriata secrezione di vasopressina, Sindrome da insufficiente produzione di ADH (SIADH), Sindrome della secrezione inadeguata dell'ormone antidiuretico, SIADH, Sindrome di Schwartz-Bartter, Sindrome da inappropriata secrezione di ADH (SIADH), Sindrome da insufficiente produzione di ADH
Dutch deficiënte ADH secretie, syndroom van ADH secretiedeficiëntie, deficiënte ADH secretiesyndroom, ADH-deficiëntie, deficiëntie ADH, ADH-secretiedeficiëntie, deficiënte vasopressinesecretie, syndroom van ADH-deficiëntie, SIADH; (syndroom van inadequate secretie van antidiuretisch hormoon), antidiuretisch; hormoon, inadequate secretie (SIADH), antidiuretisch; hormoon-syndroom (SIADH), hormoon; secretie, antidiuretisch, inadequaat (syndroom), hormoonsecretie; antidiuretisch, inadequaat (syndroom), inadequaat; secretie antidiuretisch hormoon (syndroom), inadequate secretie van antidiuretisch hormoon; syndroom, secretie; hormoon, antidiuretisch, inadequaat (syndroom), syndroom; inadequate secretie van antidiuretisch hormoon, Syndroom van inadequate secretie van antidiuretisch hormoon [SIADH], antidiuretisch hormoon-secretiedeficiëntie, ADH-syndroom, inappropriate, Antidiuretisch hormoon, inadequate secretie, Inadequate-vasopressinesecretiesyndroom, Inappropriate ADH-syndroom, SIADH, Schwartz-Bartter-syndroom, Syndroom, inappropriate ADH-
French Taux d'ADH inapproprié, Syndrome d'antidiurèse inappropriée, Syndrome de sécrétion inapprop d'ADH, Sécrétion d'ADH inappropriée, Syndrome d'ADH inappropriée, Syndrome de sécrétion inapp d'ADH, Sécrétion inappropriée d'hormone antidiurétique, Sécrétion inappropriée de vasopressine, SECRETION INAPPROPRIEE D'ADH, TROUBLE DE LA SECRETION D'ADH, Sécrétion d'hormone antidiurétique inappropriée, SIADH, Syndrome de Schwartz-Bartter, Syndrome de sécrétion inappropriée d'ADH (SIADH), Syndrome de sécrétion inappropriée d'ADH, Syndrome de sécrétion inappropriée d'hormone antidiurétique
German unangemessene ADH-Sekretion, unangemessene Vasopressin-Sekretion, ADH unangemessene Sekretion, unangemessenes ADH, Syndrom unangemessene ADH-Sekretion, ADH unangemessen, unangemess. ADH-Sekretion Syndrom, Syndrom unangemess ADH-Sekretion, SYNDROM BARTTER, SYNDROM DER INADAEQUATEN ADH SEKR, Syndrom der inadaequaten Sekretion von Adiuretin, unangemessene antidiuretische Hormonsekretion, SIADH, Schwartz-Bartter-Syndrom, ADH-Sekretionssyndrom, inadäquates, Antidiuretisches Hormon, inadäquate Sekretion, Inadäquate ADH-Sekretion, Syndrom, Inadäquates Vasopressinsekretionssyndrom, Syndrom der inadäquaten ADH-Sekretion
Portuguese Síndrome de hormona antidiurética inapropriada, Síndrome de secreção de HAD inapropriada, Secreção inapropriada de HAD, Síndrome de HAD inapropriada, HAD inapropriada, Síndrome de secreção inapropriada de HAD, Secreção inapropriada de vasopressina, SASHAD, SINDROME DA SECR INAPROPR DE ADH, Secreção inapropiada de hormona antidiurética, SIHAD, Secreção Inadequada de Hormônio Antidiurético, Síndrome da Secreção Inadequada de Vasopressina, Síndrome de Schwartz-Bartter, Síndrome de Secreção Inadequada de HAD
Spanish HAD inapropiada, SIADH, Secreción inadecuada de ADH, Síndrome de secreción inadecuada de ADH, Secreción inapropiada de vasopresina, Syndrome of inappropriate secretion of antidiuretic hormone, ADH, SINDROME SECRECION INADECUAD, SIHAD (trastorno), SIHAD, síndrome de Schwartz - Bartter, síndrome de secreción inadecuada de ADH, síndrome de secreción inadecuada de vasopresina, síndrome de secreción inapropiada de ADH, Secreción inadecuada de hormona antidiurética, SSIDH, Secreción Inadecuada de Hormona Antidiurética, Síndrome de Schwartz-Bartter, Síndrome de Secreción Inadecuada de ADH, Síndrome de Secreción Inapropiada de Vasopresina, Secrecion Inadecuada de Hormona Antidiuretica, Sindrome de Schwartz-Bartter, Sindrome de Secrecion Inadecuada de ADH, Sindrome de Secrecion Inapropiada de Vasopresina
Japanese SIADH, ADH不適合分泌, 抗利尿ホルモン分泌不適合症候群, バソプレシン不適合分泌, 抗利尿ホルモン不適合分泌, コウリニョウホルモンフテキゴウブンピ, バソプレシンフテキゴウブンピツ, ADHフテキゴウブンピ, バソプレシンフテキゴウブンピ, SIADH, コウリニョウホルモンフテキゴウブンピツ, コウリニョウホルモンブンピツフテキゴウショウコウグン, ADHフテキゴウブンピツ, コウリニョウホルモンフテキゴウブンピショウコウグン, コウリニョウホルモンブンピフテキゴウショウコウグン, コウリニョウホルモンフテキゴウブンピツショウコウグン, シュワルツ・バーター症候群, ADH不適合分泌症候群, ADH過剰分泌症候群, ADH分泌異常症候群, Schwartz-Bartter症候群, 不適切ADH症候群, 抗利尿ホルモン分泌異常, 抗利尿ホルモン分泌異常症候群, 抗利尿ホルモン過剰分泌症候群, ADH分泌異常症, Schwarz-Bartter症候群, シュワルツ-バーター症候群, 抗利尿ホルモン不適合分泌症候群
Swedish SIADH
Czech SIADH, syndrom nepřiměřené sekrece ADH, Nevhodná sekrece vasopresinu, Nepřiměřená sekrece ADH, Syndrom nevhodné sekrece ADH, Nevhodná sekrece ADH, Syndrom nevhodné sekrece antidiuretického hormonu, Nepřiměřený ADH, Syndrom nevhodného ADH, Nevhodný ADH
Finnish Antidiureettisen hormonin epäasianmukaisen erityksen oireyhtymä
Russian SHVARTSA-BARTERA SINDROM, ANTIDIURETICHESKII GORMON, POSTOIANNOI SEKRETSII SINDROM, ANTIDIURETICHESKII GORMON, NESOOTVETSTVUIUSHCHAIA SEKRETSIIA, ADG, POSTOIANNOI SEKRETSII SINDROM, АДГ, ПОСТОЯННОЙ СЕКРЕЦИИ СИНДРОМ, АНТИДИУРЕТИЧЕСКИЙ ГОРМОН, НЕСООТВЕТСТВУЮЩАЯ СЕКРЕЦИЯ, АНТИДИУРЕТИЧЕСКИЙ ГОРМОН, ПОСТОЯННОЙ СЕКРЕЦИИ СИНДРОМ, ШВАРЦА-БАРТЕРА СИНДРОМ
Korean 항이뇨 호르몬 분비 이상 증후군
Polish Zespół nieprawidłowego ADH, Wydzielanie hormonu antydiuretycznego nieprawidłowe, Zespół Schwartza-Barttera, SIADH
Hungarian nem megfelelő ADH termelés, Túlzott vasopressin secretio, Túlzott ADH-elválasztásos syndroma, Túlzott antidiuretikus hormon secretio, Inadekvat ADH secretiós syndroma, Inadekvát ADH-secretiós syndroma, SIADH, Inadequat ADH secretiós syndroma, ADH-túltermelés, Túlzott ADH