Chemical Examination (Pdf).pdf

1. Chemical Examination of
Urine Sample

2. Urine report
 Physical examination.
 Chemical examination.
 Microscopical examination.

3. Urine Report
• .

4. 1. Determination of Protein
2. Determination of Blood
3. Determination of Bile ….
4. Determination of Glucose
5. Determination of Ketone Bodies
Chemical Tests of Abnormal Constituents in Urine:

6. Proteinuria: Presence of abnormal amount of protein in urine
(1) Determination of Protein
more than (150 mg/day).
•Mechanism of Proteinuria:
(A)Glomerular Proteinuria (B) Tubular Proteinuria
• Defect in glomerulus • Defect in tubular reabsorption
(Glomerulus becomes abnormally leaky)
• Defect in filtration process •Defect in reabsorption process
•Large molecular weight protein •Small molecular weight protein
Not filtered , Not reabsorbed Filtered through glomerulus
Ex: Albumin , gamma globulin But, not reabsorbed
Ex: Beta-2-microglobulin
•Cause: •Cause:
Glomerulonephritis Urate nephropathy (DCT)
Fanconi syndrome (PCT)

7. .
Glomerular Proteinuria
Causes:
-Glomerulonephritis:
glomerulus, so the pores are enlarged
inflammation in the
and
become leaky even to large M.wt substances
including proteins.
Tubular Proteinuria
Causes:
-Urate Nephropathy: (DCT)
The deposition of uric acid in the tubules
impedes the process of DCT reabsorption.
- Fanconi Syndrome (PCT)
Caused due to either genetic defect or
exogenous factors like (heavy metal toxicity
and anticonvulsant agents (valproic acid),
which cause inadequate reabsorption of
variable small molecules including small M.wt
proteins

8. Bence-Jones protein:
•Very small Mwt abnormal proteins that may be excreted in Multiple
Myeloma
•It has unusual solubility properties. It precipitate when heated to 40-60C,
BUT becomes soluble again when boiled
❑ It is different in its characters from other usual proteins
✓Bence-johns proteins is coagulated at 40-60◦C , While it
becomes soluble when boiled.
✓Normal proteins: stay coagulated on heating even at the
boiling temperature.

9. (2) Determination of Blood
(A)Haematuria:
Presence of intact RBCs in urine
•Clinical conditions:
Renal Disease:
• Glomerulonephritis
• Urinary Stones
Other Clinical Conditions:
• Bilharziasis ( spin of the
Schistosoma egg )
(B)Haemoglobinuria:
Presence of free Hb in urine
•Clinical conditions:
• Haemolytic Anemia
• Mismatched blood transfusion
• Snake Venom (Phospholipase
A2) which cause lysis of RBCs
cell membrane and Hb release.

10. )3) Determination of Bile Salt
Lipid
Small particles
Easliy digested , absorbed
Emulsification
•Formed in: Liver
• Stored & Concentrated in: Gallbladder
Bile Salts:
• Normally excreted to the intestine,
Normally absent in urine
• Abnormally:
Presence of bile salts in urine
(cholestasis :the flow of bile is
impaired due to bile duct obstruction.
Bile Salts:
• Itching
• Bradycardia
•Steatorrhea
(Presence of abnormal amount
of fats in stool)

11. (4) Determination of Glucose
Glucosuria: Presence of abnormal amount of glucose in urine.
Causes:
• Diabetes mellitus (Hyperglycemia)
Renal threshold: Maximum capacity of kidney for reabsorption
EX: Glucose renal threshold is 180mg/dl
(If: Blood glucose level >180mg/dl, it will appear in urine)

12. (5) Determination of Ketone Bodies
• Ketonuria: Presence of ketone bodies in urine.
• Acetone
• Acetoacetic acid
• β- Hydroxy butyric acid
Causes:
• Uncontrolled Diabetes mellitus
• Starvation
• Prolonged Fasting