Specimen collection

1. Open infection and ulcerated septic foci: swab the surface exudate with sterilized saline before specimen collection, use aspiration or swab deep into the wound as far as possible and take samples close to the wound front, and take samples from the bottom of the abscess or abscess wall for more effect. For chronic infection with severe contamination, it is difficult to isolate the causative organism, and the tissue under the infected site can be taken and ground into a tissue homogenate to be inoculated in a suitable culture medium.

2. Closed abscess: After local disinfection, aspirate the abscess wall with a needle and syringe, place all the material in a sterile test tube and send it for examination, and if anaerobic infection is suspected, immediately make bedside inoculation or place it in an anaerobic transfer device for examination (the laboratory department has not carried out routine anaerobic bacteria culture yet.) However, when taking samples, it may bring in colonized bacteria unrelated to the infection process.

3. Large trauma infection: take infected tissue block or inner dressing stained with pus to send for examination.

Precautions

When bacteria are sensitive to dryness or only a small amount of specimens can be collected, put the specimens into liquid medium immediately after collection with cotton swabs, or dip the cotton swabs into a small amount of sterile saline before collecting the specimens to maintain humidity.

For specimens that cannot be sent immediately for examination, they should be stored at 4°C, with the exception of caustic specimens such as Neisseria gonorrhoeae and Neisseria meningitidis.

Whenever possible, specimens should be collected before medication is administered.