Culture tests are done to identify the causative microorganisms if there is an infection in our body. There are different kinds of culture tests; nose culture is a laboratory test that is done to identify the causative microorganisms of nose infections.
Purpose of Nose Culture
Nose culture is usually done to determine nasal diphteria, nasal mucosa inflammation and especially to identify the MRSA; means methicillin resistant staphylococcus aureus bacterium. Different types of bacteria can be found in nasal cavity for exp.
Common (adult-children) nose bacteria:
- Staphylococcus aureus
- Methicillin-resistant staphylococcus aureus (MRSA)
- Neisseria meningitis/meningococcus ; cause of meningitis
- Non pathogenic neisseria types
- Moraxella lacunata: May cause opportunistic infections sometimes it spreads to lower respiratory tract and cause pneumonia, chronic bronchitis,sinusitis
- Streptococcus pneumoniae; cause of pneumonia
- Corynebacterium (cornybacterium diphteriae cause of diphteria disease)
- Bordetella pertussis (whooping cough-pertussis disease)
- Klebsiella subsp. (klebsiella ozenae causes an infection in nose that has an bad smelling discharge)
Newborn nasal infections and bacteria
Newborn may have nasal infections that are spreaded from fecal flora like;
Nose Culture Sample Collection
- Sample collection for nose culture must be done by a professional, especially Otorhinolaryngologists ( ear-nose-throat: ENT doctor) does this sample collection for this test.
- A sterile wooden stick with a cotton swab is used to collect nose culture material.
- ENT doctor takes the sterile swab from its sterile tube carefully to avoid contamination and gently passes it through your nostril 2-2,5 cm inside.
- Doctor rotates the swab to collect infected material from your nose, you can help by tilting your head back
- ENT doctor takes the swab back and puts in the sterile tube to prevent contamination during delivery
- After the collection sample must be delivered to the laboratory as soon as possible to protect the microorganisms for nose culture test
- Same as all other culture tests, contamination is very important for nose culture test too, this is the first important step for a correct culture test result.
- Nasal secretions, pus etc. can be collected into a sterile injector or a sterile culture cup during the transportation
How the Nose Culture Test is Done ?
Nose culture samples are inoculated into the culture media for bacterial growth. Technician rubs the cotton swab on the culture media to spread and place the microorganisms all over it.
At the same time special staining process is done for microscopic analysis for bacterial identification.
If the nose culture is done to identify MRSA carriage; nose culture sample should be inoculated into a blood agar media, EMB agar is added to identify the other nasal infections.
Nose culture media is incubated in an oven at 35-37 ° for 24 hours, this means culture media waits in certain temperature for 24 hours for bacterial growth.
Nose culture media is checked after 24 hours for bacterial growth, if MRSA or other bacteria determined; antibiotic sensitivity test is done to find the effective antibiotics for the bacteria.
Sometimes yeasts may reproduce in nose culture; fungal culture should be done for identification.
Nose Culture Test Results
If there is no MRSA or other pathogenic bacterial growth; nose culture test is negative and called normal nose flora growth.
If there are bacteria growth, nose culture test result will be; MRSA growth positive.
How long does Nose Culture test take ?
After the nose culture sample collection negative results will be ready in one day but if there are bacteria growth it will take 2-3 days more for other laboratory tests.