Purpose: To evaluate the efficacy of nasopharyngeal cultures in identifying pathogens in middle-ear effusions as an alternative to cultures obtained through tympanocentesis.
Materials and methods: The study population consisted of 203 children with middle-ear effusions at the time of placement of tympanostomy tubes for recurrent otitis media or persistent otitis media with effusion. Isolates from the nasopharynx were compared with those from the middle ear to determine sensitivity, specificity, and predictive values for each of the three main pathogens.
Results: The predominant bacterial isolates from both ear and nasopharynx were Streptococcus pneumoniae, Moraxella catarrhalis, and Haemophilus influenzae. Eighty-one percent (42% highly, 39% relatively) S pneumoniae nasopharyngeal isolates were resistant to penicillin. The negative predictive value of the nasopharyngeal cultures was at least 97% for each of these predominant bacteria.
Conclusion: This study supports the conclusion that tympanocentesis is the most useful means of identifying pathogens in otitis media.