Citrate, Timed Urine

Alternate test name

Citric Acid

Lab area

Clinical Biochemistry - General

Method and equipment

Equipment : Roche Cobas Pro c503

Method : The Citric acid is changed in oxalacetate and acetate by CL (citrate lyase). This reaction is helped by a secondary one, who transforms the oxalacetate originated before (and its decarboxilated product, pyruvate) in the presence of LDH (lactate dehydrogenase), MDH (malate dehydrogenase) and NADH.
The intensity of the UV-colour at this wavelength is proportional to the concentration of Citric acid in the tested sample.

Expected turn-around time

8 days

Shipping information

Background and clinical significance

Citric acid is a weak organic acid and in biochemistry its relative salt, citrate, is an important intermediate in the Krebs cycle.

The test in urine is used to diagnose renal tubular acidosis and a tendency to form calcium kidney stones. Chronic kidney failure, diabetes, hypoparathyroidism, excessive muscle activity, ACE inhititors may decrease urine levels. May increase it an high carbohydrate diet, estrogen therapy, increase of vitamin D.