Comparison of direct-plating and broth-enrichment culture methods for detection of potential bacterial pathogens in respiratory secretions.

Objective: We compared the recovery of potential respiratory bacterial pathogens and normal flora from nasopharyngeal specimens collected from children during health and at the onset of acute otitis media (AOM) by selective direct-plating and overnight broth-enrichment.

Methods: Overall, 3442 nasal wash (NW) samples collected from young children were analysed from a 10-year prospective study. NWs were cultured by (1) direct-plating to TSAII/5 % sheep blood agar and chocolate agar plates and (2) overnight broth-enrichment in BacT/ALERT SA-broth followed by plating.

Nasopharyngeal polymicrobial colonization during health, viral upper respiratory infection and upper respiratory bacterial infection.

Objectives: We sought to understand how polymicrobial colonization varies during health, viral upper respiratory infection (URI) and acute upper respiratory bacterial infection to understand differences in infection-prone vs. non-prone patients.

Methods: Nasopharyngeal (NP) samples were collected from 74 acute otitis media (AOM) infection-prone and 754 non-prone children during 2094 healthy visits, 673 viral URI visits and 631 AOM visits.