Syndrome of inappropriate antidiuretic

Syndrome of inappropriate antidiuretic hormone is defined by water retention, dilutional hyponatraemia and decreased volume of highly concentrated urine. There are several causes which can result in SIADH, neoplasms ectopic secreting AVP, ectopic release of AVP by various diseases or drugs, exogenous administration of AVP, desmopressin, lysipressin or large doses of OT (iatrogenic SLADH). 

In addition, several other organs, like the heart, ovaty, amnion, chorion, decidua, testis, epididymis and prostate, have been reported to synthesize OT, suggesting a paracrine role for this hormone in these tissues. Ectopic AVP production by lung cancer cells or other neoplasms has been described in humans, leading to the syndrome of inappropriate antidiuretic hormone secretion. 

SIADH Syndrome of inappropriate antidiuretic hormone TID Three times daily (ter in die)... 

Paraneoplastic syndromes commonly associated with lung cancers include cachexia, hypercalcemia, syndrome of inappropriate antidiuretic hormone secretion, and Cushing s syndrome. 

Causes of nonosmotic release of arginine vasopressin, commonly known as antidiuretic hormone, include hypovolemia decreased effective circulating volume as seen in patients with congestive heart failure nephrosis cirrhosis and syndrome of inappropriate antidiuretic hormone (SIADH) release. 

FIGURE 78-1. Diagnostic algorithm for the evaluation of hyponatremia. (CHF, congestive heart failure EABV, effective arterial blood volume SIADH, syndrome of inappropriate antidiuretic hormone UNa, urine sodium concentration Uosm, urine osmolality.)... 

Because of sensory neuropathy, deep pain is often experienced by patients given vincristine. Through involvement of the glossopharyngeal nerve, throat pain may occur, as may deep pain of almost any other area of the body (31,32). Neuropathic changes are not always peripheral. Hallucinations and overall mental status changes, such as depression and/or psychosis, are also rarely reported (31,32). Another CNS effect is the syndrome of inappropriate antidiuretic hormone secretion, which is a well-characterized side effect of vincristine (31,32). 

SIADH syndrome of inappropriate antidiuretic hormone SL sublingual... 

Nephrogenic diabetes insipidus is due to resistance to action of vasopressin, and therefore DDAVP is not indicated, but some benefit may be gained by using thiazide diuretics or chlorpropamide. The syndrome of inappropriate antidiuretic hormone (SIADH) can be treated by using the antibiotic derivative demeclocycline to induce a state of vasopressin resistance and partial nephrogenic diabetes insipidus. 

Bouman WP Pinner G, lohnson H. Incidence of selective serotonin reuptake inhibitor (SSRI) induced hyponatraemia due to the syndrome of inappropriate antidiuretic hormone (SIADH) secretion in the elderly. Int 1 Geriatr Psychiatry 1998,13 12-15. 

Abbreviations CNS, central nervous system COX, cyclooxygenase Gl, gastrointestinal NSAlDs, nonsteroidal anti-inflammatory drugs SIADH, syndrome of inappropriate antidiuretic hormone secretion. From Pick DM, Cooper IW, Wade WE, et al Updating the Beers criteria for potentially inappropriate medication use in older adults Results of a U.S. consensus panel of experts. Arch Intern Med 2003 163 2716. 

The syndrome of inappropriate antidiuretic hormone secretion, with resultant hyponatremia, may be induced by carbamazepine treatment. Alcoholic patients may be at greater risk for hyponatremia. 

The syndrome of inappropriate antidiuretic hormone (SIADH) secretion is a condition in which secretion of ADH continues despite serum hypo-osmolarity. This results in fluid retention and hyponatremia that can lead to brain oedema, mental confusion and coma. The causes are hypothalamic-pituitary tumours or an ectopic vasopressin-secreting tumour. 

An 87-year-old woman received intra-articular betamethasone (Diprophos) 7 mg on three occasions for painful knee joints over 6 months. Six weeks after the last injection she developed diffuse pain and contractures in the legs, fatigue, nausea, abdominal pain, and weight loss of 6 kg. Both knee joints were tender but there was no effusion. Her serum sodium concentration was 123 mmol/1, serum osmolality 254 mosmol/kg, urine sodium 136 mmol/1, and urinary osmolality 373 mosmol/kg. The syndrome of inappropriate antidiuretic hormone secretion was diagnosed, but despite treatment she remained drowsy and hyponatremic. About a week later, she developed hypotension and symptoms of an acute abdomen. Further investigations showed that her basal cortisol concentration was low (36 nmol/1) but it increased to 481 nmol/1 after a short tetracosactide test, consistent with acute adrenal crisis. She recovered rapidly after treatment with oral hydrocortisone, but still required glucocorticoid substitution several months later. 

In an unusual case reported in detail from Saudi Arabia, a 28-year-old woman receiving gonadotropins developed acute respiratory distress, abdominal pain, and severe hyponatremia associated with the syndrome of inappropriate antidiuretic hormone secretion (SIADH) (19). A multiple pregnancy nevertheless resulted and three fetuses went to term successfully. 

Chan TY. Drug-induced syndrome of inappropriate antidiuretic hormone secretion. Causes, diagnosis and management. Drugs Aging 1997 11(1) 27—44. 

Wilke RA. Posterior pituitary sigma receptors and drug-induced syndrome of inappropriate antidiuretic hormone release. Ann Intern Med 1999 131(10) 799. 

Furosemide rarely causes the syndrome of inappropriate antidiuretic hormone secretion (SIADH) (although it has been found useful in treating some patients with SIADH who cannot tolerate water restriction (428)). In furosemide-induced cases (SEDA-7, 246), serum ADH concentrations were raised, total body sodium was normal, total body potassium greatly reduced, and intracellular water raised at the expense of extracellular fluid volume. However, such cases are rare, and no new cases have been published since this complication was reported in SEDA-7. 

The Division of Drug Experience of the US Department of Health and Welfare issued a note on five cases of the syndrome of inappropriate antidiuretic hormone secretion and drugs to which it has been attributed (1137). All involved drugs with a tricyclic structure one patient was taking imipramine, three carbamazepine, and the others the closely related muscle relaxant cyclobenz-aprine. The dosage of imipramine was 50 mg/day for 3 weeks and the patient was a 72-year-old woman. Other cases have been reported, involving amitriptyline (1137), imipramine, and protriptyline (SEDA-17,17). 

Ikegami H, Shiga T, Tsushima T, Nirei T, Kasanuki H. Syndrome of inappropriate antidiuretic hormone secretion (SIADH) induced by amiodarone a report on two cases. J Cardiovasc Pharmacol Ther 2002 7(l) 25-8. 

Patel GP, Kasiar JB. Syndrome of inappropriate antidiuretic hormone-induced hyponatremia associated with amiodarone. Pharmacotherapy 2002 22(5) 649-51. 

Aslam MK, Gnaim C, Kutnick J, Kowal RC, McGuire DK. Syndrome of inappropriate antidiuretic hormone secretion induced by amiodarone therapy. Pacing Clin Electrophysiol 2004 27(6 Pt l) 831-2. 

Castrillon JL, Mediavilla A, Mendez MA, Cavada E, Carrascosa M, Valle R. Syndrome of inappropriate antidiuretic hormone secretion (SIADH) and enalapril. J Intern Med 1993 233(1) 89-91. 

Shaikh ZH, Taylor HC, Maroo PV, Llerena LA. Syndrome of inappropriate antidiuretic hormone secretion associated with lisinopril. Ann Pharmacother 2000 34(2) 176-9. 

Garrett CA, Simpson TA Jr. Syndrome of inappropriate antidiuretic hormone associated with vinorelbine therapy. Ann Pharmacother 1998 32(12) 1306-9. 

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