Hyponatremia laboratory findings

Hyponatremia Microchapters
Home
Patient information
Overview
Historical Perspective
Classification
Pathophysiology
Causes
Differentiating Hyponatremia from other Diseases
Epidemiology and Demographics
Risk Factors
Screening
Natural History, Complications and Prognosis
Diagnosis
Diagnostic Study of Choice
History and Symptoms
Physical Examination
Laboratory Findings
Electrocardiogram
X-ray
Echocardiogram or Ultarsound
CT scan
MRI
Other Imaging Findings
Other Diagnostic Studies
Treatment
Medical Therapy
Surgery
Primary Prevention
Secondary Prevention
Cost-Effectiveness of Therapy
Future or Investigational Therapies
Case Studies
Case #1
Hyponatremia laboratory findings On the Web
Most recent articles
Most cited articles
Review articles
CME Programs
Powerpoint slides
Images
American Roentgen Ray Society Images of Hyponatremia laboratory findings All Images X-rays Echo & Ultrasound CT Images MRI
Ongoing Trials at Clinical Trials.gov
US National Guidelines Clearinghouse
NICE Guidance
FDA on Hyponatremia laboratory findings
CDC on Hyponatremia laboratory findings
Hyponatremia laboratory findings in the news
Blogs on Hyponatremia laboratory findings
Directions to Hospitals Treating hyponatremia
Risk calculators and risk factors for Hyponatremia laboratory findings

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Saeedeh Kowsarnia M.D.[2]

Overview

An elevated/reduced concentration of serum/blood/urinary/CSF/other [lab test] is diagnostic of [disease name].

OR

Laboratory findings consistent with the diagnosis of [disease name] include [abnormal test 1], [abnormal test 2], and [abnormal test 3].

OR

[Test] is usually normal among patients with [disease name].

OR

Some patients with [disease name] may have elevated/reduced concentration of [test], which is usually suggestive of [progression/complication].

OR

There are no diagnostic laboratory findings associated with [disease name].

Laboratory Findings

Biochemical evaluation for finding cause of hyponatremia :

• Serum sodium
• Serum osmolality
• Serum potassium
• Serum chloride
• Serum creatinine
• Serum other solutes
• Serum urea
• Blood Glucose
• Total protein and albumin
• Serum lipids
• Total bilirubin and direct bilirubin
• red and white cell blood count
• Serum cortisol
• Adrenocorticotropine hormone
• ADH level
• TSH
• Urine sodium
• Urine chloride
• Urine osmolality
• Fraction excretion of sodium
• Calculate GFR

Characteristics	Hypervolemic Hyponatremia	Euvolemic Hyponatremia	Hypovolemic Hyponatremia
Total body water	↑↑	↑	↔
Serum sodium level	↑	↔	↓↓
Plasma Osmolality, mOsm/kg	< 280	<280	≥ 280
Urine Osmolality, mOsm/L	> 100	> 100	> 500
Urine sodium level, mEq/L	< 20 or >20	> 20	< 10 or > 20
Differentiation of causes	> 20 mEq/L urinary sodium: Acute or chronic renal failure Fluid overload Psychogenic polydipsia < 20 mEq/L urinary sodium: Heart failure Cirrhosis Nephritic syndrome	SIADH/SIAD Adrenal insufficiency Hypothyroidism Drugs	< 10 mEq/L urinary sodium: Diuretics Extrarenal loss such as diarrhea, vomiting Severe hyperglycemia Third spacing of fluids > 20 mEq/L urinary sodium: Adrenal insufficiency Renal bicarbonate loss(renal tubal acidosis, metabolic alkalosis) Renal sodium loss (cerebral salt wasting, salt-wasting nephropathy) Diuretics

• There are no diagnostic laboratory findings associated with [disease name].

OR

• An elevated/reduced concentration of serum/blood/urinary/CSF/other [lab test] is diagnostic of [disease name].
• [Test] is usually normal among patients with [disease name].
• Laboratory findings consistent with the diagnosis of [disease name] include:
  • [Abnormal test 1]
  • [Abnormal test 2]
  • [Abnormal test 3]

• Some patients with [disease name] may have elevated/reduced concentration of [test], which is usually suggestive of [progression/complication].