1. Determination of the origin of the contamination of the patient

2. Context The patient victim of the infection was hospitalized following a surgery. During hospitalization he received each day different care and treatment : Liquid perfusion with analgesic Cleaning of the scar Catheter contaminated ? Perfusion liquid contaminated ? Physiological cleaning water contamined ? Compresses contamined ?

3. 1.Detection of bacterial contaminants on compresses

4. Materials avalaible Special agar contact dish Compress bag to test

5. 1.1. Open a bag of compresse. WARNING! The sample is realized in asepsis around the Bunsen burner. 1.2. Apply on the compresse, the “agar contact dish”. Press lightly and maintain contact approximately 10 seconds.

6. 1.3. Use eventually a forceps to peel off the compresse and after close the box 1.4. Write on the bottom of the box “Box 1” and the number of your table. Incubate 24 hours at 37°C

7. 2.Detection of bacterial contaminants in physiological cleaning water

8. Materials avalaible Agar Petri dish Physiological water (PW) to test Sterile pipette Sterile spread rake

9. 2.1. Open the “PW” bottle, and with a sterile pipette, sample 0,5 mL around WARNING! The sample is realized in asepsis around the Bunsen burner. 2.2. Put down 2 or 3 drops on the surface of the agar Petri dish

10. 2.3. With a sterile rack, spread the drops on the surface of the agar 2.4. Close the box. Write on the bottom of the box “Box 2”, and the number of your table. Incubate 24 hours at 37°C Spread rack Agar Spread through the entire surface of the agar. Do not press too hard to avoid damaging the agar

11. 3.Detection of bacterial contaminants in a catheter

12. Materials avalaible Catheter to test Agar Petri dish Swab

13. 3.1. Take the catheter with a forceps, in approximately 1 cm of the extremity WARNING! The sample is realized in asepsis around the Bunsen burner. 3.2. With the swab, rub inside the catheter next to this extremity

14. 3.3. With the swab, realize a spreading on the surface of the agar plate dish. Realize tight streaks. 3.4. Close the box. Write on the bottom of the box “Box 3”, and the number of your table. Incubate 24 hours at 37°C Spread through the entire surface of the agar. Do not press too hard to avoid damaging the agar

15. 4.Detection of bacterial contaminants in perfusion liquid

16. Materials avalaible Perfusion liquid (PL) to test Filtering system under pressio n Small agar Petri dish Bacteria filter (preinstalled on filtering system)

17. Principle of membrane filtration for bacterial detection

18. 4.1. On the pre-installed filtering system, check presence of a bacteria filter 4.2. Pour the content of the perfusion liquid (PL) on the center of the filter. Bacteria filter : view of the upper face WARNING! The sample is realized in asepsis around the Bunsen burner. Not to put drops on the walls of the filtering system

19. 4.3. Run the pression on the filtering system (by opening water tap) to triger vacuum, until filter all the liquid. After filtration, close the water tap to stop vacuum

20. 4.4. Take off the upper part of filtering system (removing before the big black clamp), so as to access to the filter. 4.5. With a forceps, recover the filter and deposit it immediately on a small agar Petri dish

21. After deposit, apply a light pression with the forceps to allow a good adhesion of the filter on the agar 4.6. Close the box. Write on the bottom of the box “Box 4”, and the number of your table. Incubate 24 hours at 37°C

22. 5.Results The second day, after incubation, observe the surface of different agar Petri dish to look for bacterial colonies What is the probable origin of the contamination ?