Other Urine Chemistry Tests
Urinalysis and Body
Fluids Review 496
TEST DETECTS METHOD(S) SOURCES OF ERROR COMMENTS
Microalbumin
Sulfosalicylic
acid (SSA)
Clinitest
Not detected by most urine dip-
sticks. 50-200 mg/24 hr or ACR
≥2.8 for males,≥2.0 for females
predictive of diabetic nephropathy.
Strict control of glucose & blood
pressure can prevent progression
to end-stage renal disease.
Centrifuge & test supernatant.
No longer used to confirm pos
protein by dipstick.
Watch rxn to avoid missing pass
through. Not as sensitive or spe-
cific for glucose as reagent strip.
Reacts with other reducing sug-
ars. Used to detect galactosemia
in children <2 yr.
Immunoassay on 24-hr
urine or albumin-to-
creatinine ratio (ACR)
on random sample.
Dipsticks available
for ACR.
Acid precipitation
Copper reduction
Albumin in low
concentration
All proteins, in-
cluding Bence
Jones proteins
Reducing
substances
False pos: radiographic dyes,
tolbutamide, some antibiotics,
turbid urine
False neg: highly buffered
alkaline urine
False pos: ↑ascorbic acid
False neg: “pass through”
(Due to ↑concentration. Goes
through orange, returns to
green. Repeat using 2-drop
method)
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