title: Correlation of nasopharyngeal cultures prior to and at onset of acute otitis media with middle ear fluid cultures.
abstract: BACKGROUND
  We sought to determine if nasopharyngeal (NP) cultures taken at times of healthy visits or at onset of acute otitis media (AOM) could predict the otopathogen mix and antibiotic-susceptibility of middle ear isolates as determined by middle ear fluid (MEF) cultures obtained by tympanocentesis.
  
  
  METHODS
  During a 7-year-prospective study of 619 children from Jun 2006-Aug 2013, NP cultures were obtained from 6-30 month olds at healthy visits and NP and MEF (by tympanocentesis) at onset of AOM episodes.
  
  
  RESULTS
  2601 NP and 530 MEF samples were collected. During healthy visits, S. pneumoniae (Spn) was isolated from 656 (31.7%) NP cultures compared to 253 (12.2%) for Nontypeable Haemophilus influenzae (NTHi) and 723 (34.9%) for Moraxella catarrhalis (Mcat). At onset of AOM 256 (48.3%) of 530 NP samples were culture positive for Spn, 223 (42%) for NTHi and 251 (47.4%) for Mcat, alone or in combinations. At 530 AOM visits, Spn was isolated from 152 (28.7%) of MEF compared to 196 (37.0%) for NTHi and 104 (19.6%) for Mcat. NP cultures collected at onset of AOM but not when children were healthy had predictive value for epidemiologic antibiotic susceptibility pattern assessments.
  
  
  CONCLUSIONS
  NP cultures at onset of AOM more closely correlate with otopathogen mix than NP cultures at healthy visits using MEF culture as the gold standard, but the correlation was too low to allow NP cultures to be recommended as a substitute for MEF culture. For epidemiology purposes, antibiotic susceptibility of MEF isolates can be predicted by NP culture results when samples are collected at onset of AOM.
authors.affiliation: Center for Infectious Diseases and Immunology, Rochester General Hospital Research Institute, 1425 Portland Avenue, 14621, Rochester, NY, USA. ravinder.kaur@rochestergeneral.org.
authors.forename: Ravinder
authors.initials: R
authors.lastname: Kaur
authors.affiliation: Center for Infectious Diseases and Immunology, Rochester General Hospital Research Institute, 1425 Portland Avenue, 14621, Rochester, NY, USA. katerina.czup@rochestergeneral.org.
authors.forename: Katerina
authors.initials: K
authors.lastname: Czup
authors.affiliation: Otitis Media Research Center, Legacy Pediatrics, Rochester, NY, USA. jrcasey1@me.com.
authors.forename: Janet R
authors.initials: JR
authors.lastname: Casey
authors.affiliation: Center for Infectious Diseases and Immunology, Rochester General Hospital Research Institute, 1425 Portland Avenue, 14621, Rochester, NY, USA. michael.pichichero@rochestergeneral.org.|Otitis Media Research Center, Legacy Pediatrics, Rochester, NY, USA. michael.pichichero@rochestergeneral.org.
authors.forename: Michael E
authors.initials: ME
authors.lastname: Pichichero
mesh_terms: D000208:Acute Disease; D017677:Age Distribution; D018929:Cell Culture Techniques; D002675:Child, Preschool; D024901:Drug Resistance, Multiple, Bacterial; D005260:Female; D006193:Haemophilus influenzae / Q000187:drug effects / Q000302:isolation & purification*; D006801:Humans; D007223:Infant; D008297:Male; D001936:Moraxella catarrhalis / Q000187:drug effects / Q000302:isolation & purification*; D009305:Nasopharynx / Q000382:microbiology*; D010034:Otitis Media with Effusion / Q000188:drug therapy / Q000382:microbiology*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D013296:Streptococcus pneumoniae / Q000187:drug effects / Q000302:isolation & purification*