This site is intended for healthcare professionals

Sign in
Go to /sign-in page

You can view 5 more pages before signing in

Diagnosis of SIADH

Last reviewed dd mmm yyyy. Last edited dd mmm yyyy

Authoring team

The following criteria should be fulfilled for a diagnosis of SIADH to be made:

  • plasma sodium concentration <135 mmol/l
  • plasma osmolality <280 mOsmol/kg
  • urine osmolality > 100 mOsmol/kg
  • urinary sodium concentration >30mmol/L
  • patient clinically euvolaemic
  • absence of clinical or biochemical features of adrenal and thyroid dysfunction.
  • no diuretic use (recent or past) (1,2)

The following investigations could be carried out in SIADH

  • urea and electrolytes
  • plasma and urine osmolality
  • urinary sodium
  • thyroid function tests
  • a short synacthen test (1)
  • chest and skull radiographs may be useful in excluding other causes of SIADH.

Note:

  • it is important to exclude diuretic use (especially thiazides), hypothyroidism and adrenal insufficiency before the diagnosis of SIADH is made (3)

Reference:

Create an account to add page annotations

Create a free account

Add information to this page that would be handy to have on hand during a consultation, such as a web address or phone number. This information will always be displayed when you visit this page

The content herein is provided for informational purposes and does not replace the need to apply professional clinical judgement when diagnosing or treating any medical condition. A licensed medical practitioner should be consulted for diagnosis and treatment of any and all medical conditions.

Connect

Copyright 2024 Oxbridge Solutions Limited, a subsidiary of OmniaMed Communications Limited. All rights reserved. Any distribution or duplication of the information contained herein is strictly prohibited. Oxbridge Solutions receives funding from advertising but maintains editorial independence.