Urine analysis or urinalysis is a very basic and simple examination, but of great importance in the preliminary diagnosis and detection of many diseases.
Under normal condition, kidneys— which act as a primary excretory organ—dispose unnecessary substances to provide balance and homeostasis in the body. At the same time, the kidneys also filter and reabsorb substances that are still needed by the body.
Determination of decreased or increased amount of substances excreted by the kidneys provides a significant screening test for the detection of many diseases.
Correlation of Hemolytic Disorder with Substances Found in the Urine
Hemolytic diseases occur when there is an increased destruction of red blood cells inside the body. Large amount of free hemoglobin is broken down into protoporphyrin and further converted to bilirubin.
The actions of bacteria in the intestines turn the bilirubin into urobilinogen which circulates back into the liver and passes through the kidneys where 0.2 to 0.9 mg/dl of urobilinogen is normally found in the urine.
If there is an excessive amount of urobilinogen that results from the degradation of hemoglobin, the greater the amount will pass through the kidneys and thus excreted in order to reduce the high amount of substances and to maintain the body's homeostasis.
Screening Test for Hemolytic Disorder Using Urine Reagent Strip
Freshly-voided, midstream-clean-catch urine is necessary for urine analysis using chemical tests to avoid false positive or false negative results.
It is also paramount to process urine as soon as possible after specimen submission to the laboratory.
The reagent urine strip is used in the detection of the upsurge amount of urobilinogen in the urine.
Urine strip is impregnated with chemicals that when come in contact with urobilinogen produces a corresponding chemical reaction that can be measured through instrumentation or by visual comparison of the produced color change with the color chart already prepared by the manufacturer.
Ranges of color can be seen in the color chart matched up with the quantitative measurement. The result is released in mg/dl.
The consequence of hemolytic disorders will result in excessive destruction of red cells and will provide increased production of urobilinogen.
Things to Remember When Undergoing Urine Urobilinogen Test
1. Void a midstream-clean-catch urine in a clean dark specimen container (midstream-clean-catch urine sample is necessary to inhibit contamination with squamous epithelial cells; dark container is a must because bilirubin and urobilinogen are easily degraded when exposed to light).
2. Present the fresh urine sample in the laboratory not longer than 1 hour after collection to hinder bacterial contamination.
3. Wait for the result after one hour after submission or wait for the releasing time according to each laboratory's protocol.
4. Correlate urine urobilinogen with the result of urine bilirubin. Hemolytic diseases will produce negative urine bilirubin, but excessive amounts of urine urobilinogen.
This is because bilirubin that are produced by excessive lysis of red cells will be broken down into urobilinogen that is excreted and occurs in the urine.
5. The result is important as a screening test, but is not used as a confirmatory test. Consult with a physician once there is detected abnormality in the result of the test.
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