Ear swab

Specimen:

Swab of pus or fluid from external meatus, placed in transport medium eg, Stuart’s medium.

Method:

Gram stain of pus.

Culture for bacteria and fungi.

Application:

Only appropriate in chronic, persistent or severe acute otitis externa;

otitis media with ruptured ear drum; or

infection following aural surgery.

Interpretation:

Pseudomonas aeruginosa, Aspergillus spp and Candida albicans may be pathogens in chronic otitis externa.

Streptococcus pneumoniae and Haemophilus influenzae are the most important pathogens in middle ear infection.

Staphylococcus aureus may be part of the normal flora, but is an important cause of infection following aural surgery.

Reference:

Carroll K and Reimer L. Clin Infect Dis 1996: 23; 442-448.