How the Test is Performed

You will be asked to cough before the test begins and then tilt your head back. A sterile cotton-tipped swab is gently passed through the nostril and into the nasopharynx, the part of the pharynx that covers the roof of the mouth. The swab is quickly rotated and then removed.

How to Prepare for the Test

There is no special preparation necessary.

How the Test Will Feel

You may experience slight discomfort and may gag.

Why the Test is Performed

The test identifies viruses and bacteria that cause upper respiratory tract symptoms. Nasopharyngeal cultures are useful in identifying respiratory viruses, and specific bacteria such as:

• Bordetella pertussis
• Neisseria meningitidis
• Staphylococcus aureus

The culture may be used to help determine which antibiotic therapy is appropriate.

Normal Results

The presence of organisms commonly found in the nasopharynx is normal.

What Abnormal Results Mean

The presence of any disease-causing virus, bacteria, or fungus means these organisms may be involved in your infection. Sometimes organisms like Staphylococcus aureus can be present without causing disease, but the test can identify resistant strains of this organism (methicillin-resistant Staphylococcus aureus, or MRSA) and patients can be isolated when necessary.

Risks

There are no risks.

Alternative Names

Culture - nasopharyngeal; Swab for respiratory viruses; Swab for Staph carriage

References

Hewlett EL. Whooping cough and other Bordetella infections. In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia,PA: Saunders Elsevier; 2011:chap 321.

Updated: 4/12/2012

Reviewed by: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and Denis Hadjiliadis, MD, Assistant Professor of Medicine, Division of Pulmonary, Allergy and Critical Care, University of Pennsylvania, Philadelphia, PA. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.