Archive for the ‘ Prac-Urine ’ Category

Pc- Physical and Chemical Characters of urine

Physical Characters of urine

1.Volume:

-1200 – 1500  ml/day

-physiological increase

  • Excess water intake
  • A high salt diet
  • A high protein diet

-Physiological decrease

  • Excess sweating
  • High temperature
  • Muscular Exercise

-Pathological variations

A.Polyuria:

  • Diabetes mellitus
  • Diabetes insipidus
  • Chronic renal failure
  • Conne’s syndrome (hyperaldosteronism)
  • Cushing syndrome (hypercortisonemia)
  • Thyrotoxicosis

B.Oliguria:

  • Burns, diarrhea, vomiting, and hemorrhage
  • Acute renal failure
  • Acute glomerulonephritis
  • Acute hepatic failure

C.Anuria:

  • Acute renal failure
  • Obstructive lesion e.g calculi
  • Neurological lesions of urinary bladder

2.Color:

-It is amber yellow due to the presence of certain pigments e.g urochrome, urobilin, and uroerythrin

-Variations in the color of urine

  • Pale yellow in case of polyuria (due to dilution of pigments)
  • Deep yellow in the case of oliguria (due to concentration  of pigments)
  • Reddish in case of hematuria
  • Orange brown in case of hemolytic jaundice
  • Greenish brown in case of obstructive, and hepatocellular jaundice
  • Black in case of melanoma ,and alkaptonuria

3.Odor:

-The fresh urine has a characteristic aromatic odor (due to volatile aromatic acids)

-On standing ,it takes the odor of ammonia

-Variations in the odor of urine

  • Offensive odor : in case of pyuria
  • Acetone odor : in case o Ketosis (e.g D.M)
  • Burnt sugar odor : in case of maple syrup urine disease

4.Reaction:

-Fresh urine has a slightly acidic PH (6)

-High protein diet makes the urine more acidic

-Excess citreous fruits, and vegetables make the urine more alkaline

5.Specific gravity:

-It depends on the total amounts of solids , mainly Na Cl, urea ,proteins, and sugar

-It decreases in case of polyuria

-It increases in case of oliguria

6.Aspect:

-Normal fresh urine is clear

-Causes of turbid urine :

  • Pyuria
  • Hematuria
  • Bacteruria
  • Chyluria
  • Crystaluria

Chemical Characters of urine

-Normal urine contains about 50 gm of solids dissolved  in about 1.5 liter of water .

The main organic solid are :

  • NPN .
  • Proteins .enzymes ,hormones , and , vitamins .
  • Sugars .
  • Organic Acids .

1) Non protein nitrogenous substances ( NPN):

  1. Urea
  2. Uric acid
  3. Creatine
  4. Creatinine
  5. Ammonia
  6. Amino acids

1- Urea :

-It is the metabolic end product of   protein metabolism

-Formation : by urea cycle of the liver .

-Excretion in urine :  15 – 35 gm /day .

-Variation

2- uric acid :

-It is the metabolic end product of purine catabolism .

-Excretion in urine : 300 – 700 mg / day .

-Gout .

3.   Creatine :

-It is formed of 3 amino acids .

-It is directly proportional to muscle mass (present as creatine  phosphate )

-Excretion in urine : less than 50 mg / day

4.  creatinine :

-It is formed from creatine phosphate .

-It is a renal function test .

-Excretion in urine : 0.8 – 2.0 gm / day

5. Ammonia :

-It is appears in urine as :

  • NH3 ( from deamination of amino acids ).
  • NH4 ( by action of glutaminase on glutamine received  by the kidneys from  other tissues

-This is significant to maintain acid  base balance in the case of acidosis

6.Amino acids :

-They  appear in urine in 2 forms :

  1. Free  ( 20 % )
  2. Conjugated   ( 80 % ) e.g  .
  • Hippuric acid
  • Phenyl Acetyl Glutamine
  • ß-Mercupturic Acid

-Amino aciduria

2) Sugars :

-Small amount of glucose ( not exceeding 150 mg /day  are excreted daily .

-Small amount of lactose , pentoses . and glucuronic  acid are excreted daily

3) Organic Acid :

  1. Oxalic Acid .
  2. Lactic Acid .
  3. Citric Acid .
  4. Short chain fatty acids .
  5. Hippuric  Acid  .
  6. Aromatic Acid

The main inorganic solids are :

  • Sodium .
  • Potassium .
  • Chloride .
  • Sulfate .

Sodium , potassium, chloride ( mainly from food )

and sulfur ( from sulfur containing amino acids,

and   sulfur   containing   vitamins )   are   mainly

excreted in urine .

N . B :

Abnormal constituents of urine :

1.Glycosuria

2.Proteinuria