OCCULT BLOOD EXAMINATION Tests for occult blood are very important to detect small bleeding that cannot be detected macroscopically or microscopically. There are various types of tests to check for occult blood, namely in this practicum we will use the occult blood test methodCombur test.This method is a modification of the benzidine method. The Combur test stick contains the following substances: 1. 3,3',5,5'-tetramethylbenzidine 52.8 μg 2. 2,5-dimethyl-2,5-dihydroperoxyhexane 297.2 μg Tool : 1. Test tube 2. Pipette 3. Applicator/stirring stick 4.StickCombur test Material : 1. Water/salt solution ±10 ml 2. Feces How to check: 1. Make a stool emulsion with water or a salt solution of approximately ±10 ml in a test tube 2. Insert the tip of the Combur test stick into the solution 3. Read the results compared to the standards provided. Results are read in no more than 10 minutes. Check key: (-) : yellow 1+ : yellow with slight green spots (ca. 5-10 ery/μL) 2+ : yellow with green spots (ca. 25 ery/μL) 3+ : greenish yellow with green spots (ca.50 ery/μL) 4+ : green (ca.250 ery/μL) STUDENT ASSESSMENT CHECKLIST No. VARIABLES 1 Reading requests, labeling (samples and specimens, object glass) 2 Observe the macroscopic specimen and record the results of the observation 3 Clean the object glass, drip the examination solution/media (physiological NaCl, Lugol) onto the object glass 4 Take the specimen with a stick, then mix it into the solution/media on the object glass until it is homogeneous 5 Discard the used stick in a waste container/basket, cover the specimen on top of the object glass with a cover glass/deck glassproperly (so there is no air) 6 Examine the specimen preparation under a microscope with a 10x objective, then 40x 7 Inspection of the stock is carried out from one end to the other in the opposite direction in a zig-zag direction 8 Record the results of the examination (note: show your finger if you find parasites, eggs, larvae, trophozoids, sequential cysts. Verify/check the correctness by the instructor) 0 1 2