Last reviewed: November 2017
Last updated: May  2017

Summary

Definition

History and exam

Key diagnostic factors

  • presence of risk factors
  • hospital stay
  • older age/nursing home resident
  • CNS manifestations
  • diarrhoea or vomiting
  • impaired thirst
  • weight loss
  • oliguria
  • orthostatic hypotension
  • decreased jugular venous pressure
  • other signs of hypovolaemia
  • polyuria, polydipsia, increased thirst

Risk factors

  • inability to drink water/limited access to water
  • infancy
  • older age
  • renal concentrating defect
  • gastrointestinal disorders
  • insensible water losses
  • diabetes insipidus
  • use of specific drugs
  • large salt intake or administration
  • traumatic brain injury
  • primary hypodipsia

Diagnostic investigations

1st investigations to order

  • serum electrolyte panel with glucose, urea, and creatinine
  • urine osmolality
  • serum osmolality
  • urine electrolytes
  • urine flow rate
  • electrolyte-free water excretion
Full details

Investigations to consider

  • desmopressin challenge test
  • serum arginine vasopressin (AVP) level
  • MRI or CT brain
  • other tests targeted at evaluating the underlying cause
Full details

Treatment algorithm

Contributors

Authors VIEW ALL

Clinical Professor of Medicine

San Francisco General Hospital

University of California San Francisco

San Francisco

CA

Disclosures

RS declares that he has no competing interests.

Professor Emeritus of Medicine

Loyola University Chicago

Maywood

IL

Disclosures

TSI declares that he has no competing interests.

Peer reviewers VIEW ALL

Director

Department of Internal & Emergency Medicine

Hirslanden Klinik Im Park

Zurich

Switzerland

Disclosures

GL is the author of several references cited in this monograph.

Professor of Pediatrics

University of Pittsburgh Medical School

Children's Hospital of Pittsburgh of UPMC

Pittsburgh

PA

Disclosures

MLM is the author of a number of references cited in this monograph.

Associate Director

Nephrology

Washington Hospital Center

Washington

DC

Disclosures

JHV declares that she has no competing interests.

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