Polyuria

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Polyuria
ADH3.svg

Regulation of urine production by ADH and aldosterone
ICD-10 R35
ICD-9 788.42
MedlinePlus 003146
MeSH D011141

Polyuria is a condition usually defined as excessive or abnormally large production or passage[1] of urine (at least 2.5[2] or 3[3] L over 24 hours in adults). Frequent urination is sometimes included by definition,[4] but is nonetheless usually an accompanying symptom. Increased production and passage of urine may also be termed diuresis.[5][6]

Polyuria often appears in conjunction with polydipsia (increased thirst), though it is possible to have one without the other, and the latter may be a cause or an effect. Psychogenic polydipsia may lead to polyuria.

Polyuria is physiologically normal in some circumstances, such as cold diuresis, altitude diuresis, and after drinking large amounts of fluids.

Causes[edit]

The most common cause of polyuria in both adults and children is uncontrolled diabetes mellitus,[3] causing an osmotic diuresis. In the absence of diabetes mellitus, the most common causes are excessive secretion of aldosterone due to adrenal cortical tumour, primary polydipsia (excessive fluid drinking), central diabetes insipidus and nephrogenic diabetes insipidus.[3]

Polyuria may also be due to various chemical substances (diuretics, caffeine, ethanol). It may also occur after supraventricular tachycardias, during an onset of atrial fibrillation, childbirth, and the removal of an obstruction within the urinary tract. Diuresis is restrained by antidiuretics such as ADH, angiotensin II and aldosterone.

Cold diuresis is the occurrence of increased urine production on exposure to cold, which also partially explains immersion diuresis.

Substances that increase diuresis are called diuretics.

Substances that decrease diuresis allow more vasopressin or antidiuretic hormone (ADH) to be present in the kidney.

High-altitude diuresis occurs at altitudes above 10,000 ft and is a desirable indicator of adaptation to high altitudes. Mountaineers who are adapting well to high altitudes experience this type of diuresis. Persons who produce less urine even in the presence of adequate fluid intake probably are not adapting well to altitude.[7]

List of causes[edit]

Urinary system;

Hormonal;

Circulation;

Neurologic;

Rheumatology;

Other;

References[edit]

  1. ^ thefreedictionary.com > polyuria. Citing:
    • "Excessive passage" - The American Heritage Medical Dictionary Copyright 2007
    • "Excessive production" - Gale Encyclopedia of Medicine. Copyright 2008
    • "the formation and excretion" - Saunders Comprehensive Veterinary Dictionary, 3 ed. 2007
  2. ^ http://www.nlm.nih.gov/medlineplus/ency/article/003146.htm Last Editorial Review: 9/30/2009
  3. ^ a b c merck.com > Polyuria: A Merck Manual of Patient Symptoms podcast. Last full review/revision September 2009 by Seyed-Ali Sadjadi, MD
  4. ^ Acknowledgements patient.co.uk > Polyuria By Dr Colin Tidy. Document ID: 2632. Document Version: 21. Document Reference: bgp113. Last Updated: 6 Jul 2009
  5. ^ MedicineNet.com > Definition of Diuresis Last Editorial Review: 8/20/2002
  6. ^ thefreedictionary.com > diuresis Retrieved on June 13, 2010
  7. ^ Hackett, Peter H. Mountain Sickness, The American Alpine Club, 1980. pp. 54, 62)
  8. ^ eMedicine - Hyperparathyroidism : Article by James LaBagnara