Overview of tests done in urinalysis lab

(a) Dipstick – 2 types
1) five-patch test strip to determine quantity of pH, protein, glucose, ketone bodies and blood in urine.
2) 10-patch test strip for glucose, bilirubin, ketone, specific gravity, blood, pH, protein, urobilinogen, nitrite and leukocytes in urine.

The dipstick test is performed routinely. However, it is only done if the sample is that of an outpatient or patient with renal disease. Usually, only the 1st dipstick consisting of 5 tests is used. The 10-patch test stip is used only if the specific tests, such as bilirubin and urobilinogen, are requested.

(b) Microscopic analysis (using KOVA glasstic 10 with grid slide)
This is used to determine or identify cells that may be found in urine samples.9 microlitre of urine is pipetted into a notch on the KOVA glasstic slide chamber. The slide consist of grid lines that is used to count the number of specific cells. Examples of possible cells found in urine includes:
1) White blood cell
2) Red Blood Cell
3) Casts
4) Crystals such as cystine and triple phosphates
5) Microorganism (bacteria, yeast, spermatozoa)

An example of a KOVA slide. (taken from http://www.mlo-online.com/articles/0104/mlo0104prodfocus.htm)

- Internal QA -
1) The tests should be performed within 2 hrs of collection. The chemical composition of urine (e.g: pH,glucose and bilirubin) may change after 2 hrs. Furthermore, any formed elements such as crystals that are actually present in the urine, may begin to deteriorate and become unrecognizable.

2) For routine urinalysis, the preferred type of urine specimen is that of a midstream clean catch. This is so as that type of specimen reflects the urine composition in the bladder and the kidney

3) Dipstick Testing
(a) The dipsticks must be protected from moisture, light, heat and volatile chemicals as they deteriorate easily.
(b) They also deteriorate with time and hence should not be used after the expiration date.
(c) Each dipstick bottle is tested routinely (daily, before dipsticks are used) for results against known commercial controls. Each of the chemical parameters of the dipstick is evaluated and the results recorded (e.g: protein 2+, pH 6.5) By doing this, the technologist performance can be compared on a daily basis and the reactivity of the strips can be checked against known standards.
(d) Only a few strips should be removed at a time and the container should be closed tightly immediately after taking out the strips.
(e) The amount of time required for the colour reaction to develop on the strip varies with each test (e.g: 2 minutes for leucocytes). A timing device (stopwatch) is used and the manufacturer’s timing instructions should be followed strictly. The strip should be held close to the colour chart in adequate lighting when reading the results.