RENAL FUNCTION TESTS
• Renal function tests are the group of tests that are performed to assess
the functions of kidney.
• Renal function tests are of three types:
A. Examination of urine alone
B. Examination of blood alone
C. Examination of blood and urine
,A. EXAMINATION OF URINE – URINALYSIS
• Urinalysis is a group of diagnostic tests performed on the sample of
urine to assess the functions of kidney.
• Urinalysis is done by:
i. Physical examination
ii. Microscopic examination
iii. Chemical analysis.
PHYSICAL EXAMINATION
1. Volume
• Increase in urine volume indicates increase in protein catabolism and
renal disorders such as chronic renal failure, diabetes insipidus and
diabetes mellitus (glycosuria).
2. Color
• Normally urine is pale yellow (straw) colored.
• Abnormal coloration of urine is due to several causes such as jaundice,
hematuria, hemoglobinuria, medications and excess urobilinogen.
, 3. Appearance
• Normally urine is clear.
• It becomes turbid in both physiological and pathological conditions.
• Physiological conditions causing turbidity of urine are precipitation
of crystals and presence of mucus.
• Pathological conditions causing turbidity are presence of blood
cells, bacteria or yeast.
4. Specific Gravity
• Measure of relative amount of solids in urine.
• It is low in diabetes insipidus and high in diabetes mellitus, acute
renal failure and excess medications.
5. Osmolarity
• Osmolarity of urine decreases in diabetes insipidus.
6. pH
• Measurement of pH is useful in determining the metabolic or
respiratory acidosis or alkalosis.
• The pH decreases in renal diseases.
• Renal function tests are the group of tests that are performed to assess
the functions of kidney.
• Renal function tests are of three types:
A. Examination of urine alone
B. Examination of blood alone
C. Examination of blood and urine
,A. EXAMINATION OF URINE – URINALYSIS
• Urinalysis is a group of diagnostic tests performed on the sample of
urine to assess the functions of kidney.
• Urinalysis is done by:
i. Physical examination
ii. Microscopic examination
iii. Chemical analysis.
PHYSICAL EXAMINATION
1. Volume
• Increase in urine volume indicates increase in protein catabolism and
renal disorders such as chronic renal failure, diabetes insipidus and
diabetes mellitus (glycosuria).
2. Color
• Normally urine is pale yellow (straw) colored.
• Abnormal coloration of urine is due to several causes such as jaundice,
hematuria, hemoglobinuria, medications and excess urobilinogen.
, 3. Appearance
• Normally urine is clear.
• It becomes turbid in both physiological and pathological conditions.
• Physiological conditions causing turbidity of urine are precipitation
of crystals and presence of mucus.
• Pathological conditions causing turbidity are presence of blood
cells, bacteria or yeast.
4. Specific Gravity
• Measure of relative amount of solids in urine.
• It is low in diabetes insipidus and high in diabetes mellitus, acute
renal failure and excess medications.
5. Osmolarity
• Osmolarity of urine decreases in diabetes insipidus.
6. pH
• Measurement of pH is useful in determining the metabolic or
respiratory acidosis or alkalosis.
• The pH decreases in renal diseases.
