week 10!

Subject title: Clinical Chemistry
Name of test: Urine Microalbumin Qualitative Test


Yay! 10 more weeks to go =)


Principle:

• Urine Microalbumin Qualitative Test is a screening test to determine the presence of albumin and creatinine in urine. An albumin-to-creatinine ratio is also determined since the amount of albumin in the urine and the concentration of urine varies throughout the day, hence if we were to take the albumin results, it would not be very accurate. Creatinine on the other hand is excreted out on a consistent basis and its level is relatively stable in the urine. This test can be considered semi-quantitative, however it is not a confirmatory test.
  

• This test involves plastic strips which contain two reagent areas that test for albumin and creatinine. The strips are then read instrumentally using CLINITEK STATUS®

• Normally, albumin is present in urine at concentrations of less than 20mg/L. Measurements of 20-200mg/L indicates microalbuminuria whereas results of >200mg/L indicate clinical albuminuria. It is abnormal to have protein in your urine as the glomerular basement membrane is actually poorly permeable to it. Microalbuminuria can be an indication of glomerular damage.

• Test principle for albumin: It is based on dye binding using a high affinity sulfonephthalein dye. If albumin is present, the colour of the reagent area that test for albumin will change to blue. The colour ranges from pale green to aqua blue.
  

• Test principle for creatinine: It is based on the peroxidase-like activity of a copper creatinine complex that catalyzes the reaction of diisopropyl-benzene dihydroperoxide and 3,3,'5,5'-tetramethylbenzidine. The colour ranges from orange through green to blue.

Materials:

1. Patients' urine


2. CLINITEK® Microalbumin Reagent Strips

Retrieved August 31,2008, from http://diagnostics.siemens.com/webapp/wcs/stores/servlet/ProductDisplay~q_catalogId~e_-111~a_catTree~e_100001,1015867~a_langId~e_-111~a_productId~e_172993~a_storeId~e_10001.htm

3. CLINITEK® STATUS analyser

Retrieved 31 August, 2008, from http://diagnostics.siemens.com/webapp/wcs/stores/servlet/ProductDisplay?productId=172991&storeId=10001&langId=-111&catalogId=-111&catTree=100001,1015867

Method:

1. Check labels on the urine container to ensure the name of the patient tally

2. Key in the patient's lab no in the analyser

3. Dip a reagent strip into the sample making sure both reagent areas are wet

4. Remove the strip and drag the edge of the strip against the rim of the urine container to remove excess urine

5. Place the reagent strip with the reagent areas facing up, onto the analyser test table. Press START and the table will be automatically pulled into the analyser where the strip will be read.

6. Record the results displayed on the analyser

Results:

• The results are determined by the Albumin-to-Creatinine Ratio (A:C) which is calculated automatically by the analyser
• The results are recorded as NEGATIVE when the A:C displayed is <30mg/g>
• The results are recorded as ABNORMAL when the A:C displayed is 30-300mg/g
• The results are recorded as HIGHLY ABNORMAL when the A:C displayed is >300mg/g

Note:

• Both ABNORMAL and HIGHLY ABNORMAL samples will be confirmed with the quantitative test which can be carried out in the machines COBAS or MODULAR P used in our lab
  

Nur Farhana Binte Ramlan
0604834B