HealthFlex
×
  • Home
  • Immunology Book
  • Lab Tests
    • Hematology
    • Fluid analysis
    • CSF
    • Urine Analysis
    • Chemical pathology
    • Blood banking
    • Fungi
    • General pathology
    • Immune system
    • Microbiology
    • Parasitology
    • Pathology
    • Tumor marker
    • Virology
    • Cytology
  • Lectures
    • Bacteriology
    • Liver
    • Lymph node
    • Mycology
    • Virology
  • Blog
    • Economics and technical
    • Fitness health
    • Mental health
    • Nutrition
    • Travel
    • Preventive health
    • Nature and photos
    • General topic
  • Medical Dictionary
  • About Us
  • Contact

Urine 24 hours Urea, Urine Urea Nitrogen/24 Hours

March 22, 2021Lab TestsUrine Analysis

Sample

  1. The test sample is urine.
  2. Collected urine for 24 hours.
  3. The urine sample is stable at 4 to 8 °C for 4 days or preserves with thymol to avoid bacterial action.
    1. Discard the first urine sample and note the time. Add the last sample of urine to the container.
    2. 10 grams of boric acid can be used as preservative/24 hours.

Indications

  1. This test is mainly used to:
    1. Determine protein metabolism.
    2. It determines the amount of protein needed by severely ill patients.
    3. It gives information about kidney function.
    4. It can monitor kidney disease.
    5. Patients with confirmed or suspected protein digestion and absorption problems.
    6. Patients on long-term enteral nutrition or parenteral nutrition.

Pathophysiology

  1. Urea formula =     
  2. Urea is the major excretory product of protein metabolism.
Source of Urea formation

Source of Urea formation

Source of Urea formation

Source of Urea formation

  1. Urea is a low molecular weight substance and is easily excreted by glomeruli and is mostly excreted in the urine.
  2. The kidneys excrete urea, so the excretion of urea can reflect kidney function.
    1. It is synthesized in the liver, carried to the kidney, filtered through the glomeruli, mostly into the urine.
Urea excretion cycle

Urea excretion cycle

  1. 40% is reabsorbed by passive diffusion.
  2. The rate of absorption depends upon:
    1. Urine flow rate.
    2. The degree of hydration.
  3. 10 % of urea is excreted through:
    1. GI tract.
    2. Skin.
  4. Blood urea level depends upon:
    1. Renal function and perfusion.
    2. The protein content of the diet.
    3. Amount of protein catabolism.

Normal

Source 1

Urine urea nitrogen

  • 12 to 20 g/day (428.4 to 714 mmol/day).

Another source

  • 6 to 7 G /24 hours ( 60 to 90 mg/dL )
  • Another reference says:
    • 7 to 20 g /total volume
    • 12 to 24 g /24 hours.
  • This also depends upon the protein intake.

The decreased urine urea level is seen in:

  1. Malnutrition.
  2. Too little amount of protein in the diet.
  3. Kidney dysfunction.
  4. Increased reabsorption.

The increased level is seen in:

  1. Excessive protein intake.
  2. Increased protein catabolism.

    Normal urine picture:

    Physical features Chemical features Microscopic findings
    1. Color = Pale yellow or amber
    2. Appearance = Clear to slightly hazy
    3. pH = 4.5 to 8.0
    4. Specific gravity = 1.015 to 1.025
    1. Blood = Negative
    2. Glucose = Negative
    3. Ketones= Negative
    4. Protein = Negative
    5. Bilirubin = Negative
    6. Urobilinogen = Negative (±)
    7. Leucocyte esterase = Negative
    8. Nitrite for bacteria = Negative
    1. RBCs = Rare or Negative
    2. WBC = Rare or Negative
    3. Epithelial cells = Few
    4. Cast = Negative (Occasional hyaline)
    5. Crystal = Negative (Depends upon the pH of the urine)
    6. Bacteria = Negative

     


Possible References Used
Go Back to Lab Tests

Add Comment Cancel


  • Lab Tests
    • Blood banking
    • Chemical pathology
    • CSF
    • Cytology
    • Fluid analysis
    • Fungi
    • General pathology
    • Hematology
    • Immune system
    • Microbiology
    • Parasitology
    • Pathology
    • Tumor marker
    • Urine Analysis
    • Virology

About Us

Labpedia.net is non-profit health information resource. All informations are useful for doctors, lab technicians, nurses, and paramedical staff. All the tests include details about the sampling, normal values, precautions, pathophysiology, and interpretation.

[email protected]

Quick Links

  • Blog
  • About Us
  • Contact
  • Disclaimer

Our Team

Professor Dr. Riaz Ahmad Bhutta

Dr. Naheed Afroz Syed

Dr. Asad Ahmad, M.D.

Dr. Shehpar Khan, M.D.

Copyright © 2014 - 2023. All Rights Reserved.
Web development by Farhan Ahmad.