Test : Nasopharyngeal culture
Indications : The test is carried out to detect viruses and bacteria that cause upper respiratory tract infections such as
Bordetella pertussis, Neisseria meningitides and Staphylococcus aureus.
The study also helps to assess the type of
antibiotic therapy that is appropriate to counter these microbes.
No preparation is required prior to the test. Talk to the doctor regarding any medication that you may be taking.
For sample collection the patient is asked to cough and then tilt head backward.A sterile, cotton-tipped swab is then gently passed into the nasopharynx, through the nostril, and quickly rotated before being removed.
The sample is then transferred to the laboratory where it is cultured in a petri dish containing appropriate media.
Physiology : The nose and throat areas (nasopharynx) harbor a population of “normal flora” consisting of several species of
streptococcus and other bacteria. Sometimes, infection- causing organisms co-exist along with the normal flora and may even dominate them.
Nasopharyngeal culture is carried out to detect
upper respiratory tract infections. Samples for the culture include secretions from the upper part of the throat or behind the nose.
Normal Range : Normal nasopharyngeal flora
Interpretation : Normal
Only normal flora of the nasopharynx will be present.
Abnormal
The presence of micro organisms such as Staphylococcus aureus, N. meningitidis or other disease- causing
virus, bacteria, or fungus can be detected.
A positive nasopharyngeal culture may reflect infection of
tonsils, oropharynx, nasopharynx, and sinuses.
Sample : Nasopharyngeal swab.
Test Method : Aerobic culture
References :
1. http://www.nlm.nih.gov/medlineplus/ency/article/003747.htm