Specimen Cultures

Specimens (a sample for medical testing)

Obtained from a variety of sites, including lesions on the skin or from the eyes, ears, nose, throat, or other body openings.

The medium provides nourishment for the cultured organism and keeps it moist so that it can be examined.

Specimen must not be allowed to be in contact with any other substances or objects once obtained.

Can be obtained & transported in a variety of STERILE collection containers

Sterile: free of microorganisms

Prevents cross-contamination

A culture specimen placed on a slide for microscopic examination.

The swab containing the specimen is applied on the slide . The smear is air dried or heat fixed, or passed through a flame, so the organisms will stick to the slide.

After the direct smear is stained so that organisms are visible, it is examined, and the organism causing the disease is identified.

The specimen can be placed or streaked on an agar plate, aka culture plate or petri dish, or into a culture media tube.

Agar: solid medium that nourishes and moisturizes the organism. Needs incubation for 24–36 hours, and the organism is grown.

Culturing an organism. A small sample (called a colony) is placed on a slide, stained, and then examined for identification.

Exact identification sometimes requires growing a sample of the (the colony) on another special medium, helps to differentiate the microorganisms.

Organism can be isolated at this point

small, sterile disks containing different antibiotics that are placed on plate after the organism added

If grow to edge of a disk, the organism is resistant. The antibiotic would not work against the organism and would not help cure the disease.

If do not grow close to disk, the organisms are sensitive. Antibiotic would work against the organism and aid in the curing of the disease.

Dr's use to treat diseases

Technique of staining organisms to identify specific types of bacteria present.

Used to identify shape & arrangement of microorganisms

Cultures may contain pathogenic organisms or be contaminated with blood and body fluids, standard precautions must be practiced!

Use PPE- gloves, lab coat, eye protection

Wash hands frequently

Dispose of cultures properly