Ear drainage culture

Alternative names:

culture of ear drainage

How the test is performed:

A sample of ear drainage is placed on culture media in containers for the purpose of growing microorganisms (bacteria, fungus, or viruses) in the laboratory, which will later be identified under the microscope. The microbiologist inspects the cultures daily for growth. If microorganisms are detected, other tests may be initiated to determine the sensitivity of the organism to medications (sensitivity analysis). Antibiotic therapy can then be determined based on these results.

How to prepare for the test:

There is no preparation.

How the test will feel:

The specimen will be collected from a cotton swab placed gently inside the ear canal. No pain is associated with the test; however, ear pain may be present already if infection is suspected. If a myringotomy (surgical opening of the eardrum) is performed for relief of a painful, bulging tympanic membrane in otitis media, fluid will be collected at this time. Rarely, a needle may be inserted through the tympanic membrane (eardrum) to obtain a sample of the fluid.

Why the test is performed:

The test may be performed for an infection of the outer ear (see otitis externa; acute), as a routine part of myringotomy, otitis media with ruptured eardrum and draining fluid, and otitis media not responding to treatment. Most ear infections are diagnosed by clinical symptoms rather than by obtaining a culture.