title: Cytology of middle ear fluid during acute otitis media.
abstract: BACKGROUND
  Limited information is available on the cellular characteristics of the middle ear fluid (MEF) during acute otitis media (AOM).
  
  
  OBJECTIVE
  To determine the white blood cell (WBC) composition of the MEF in AOM before and during antibiotic therapy.
  
  
  METHODS
  Total WBC and differential counts were determined in the MEF of 96 infants and children (ages 2 weeks to 3 years) with AOM who were receiving antibiotics. WBC counts were reported as number of WBC/mg MEF (mean +/- sd).
  
  
  RESULTS
  One hundred forty-five MEF samples were obtained by tympanocentesis at enrollment (Day 1), and 36 samples were collected on Days 4 to 5 after initiation of antibiotic therapy. Sixty-one percent of the patients were <1 year of age, and 38% were receiving antibiotic therapy at enrollment. Twenty-eight MEF samples were paired (same ear, Day 1 and Days 4 to 5). One hundred twelve pathogens were isolated from 95 of 145 (66%) culture-positive samples obtained on Day 1: 67 Haemophilus influenzae, 40 Streptococcus pneumoniae and 5 others. MEF WBC counts were lower on Day 1 in patients who had received previous antibiotic therapy than in those who had not (432.4+/- 412.8 vs. 590.5 +/- 436.8, P = 0.03). WBC counts were higher on Day 1 in culture-positive than in culture-negative samples (603.9 +/- 504.9 vs.421.4 +/- 373.4, P = 0.02). WBC counts were higher on Day 1 in MEF samples positive for S. pneumoniae than in those positive for H. influenzae (799.2 +/- 641.5 vs.506.4 +/- 401.9, P = 0.04). There were no differences in the number of neutrophil WBC present in the samples obtained on Day 1 vs. Days 4 to 5 or between samples positive vs.samples negative for bacterial pathogens.
  
  
  CONCLUSIONS
  WBC counts were higher in the MEF of patients with culture-positive AOM than in those with culture-negative AOM and in those with AOM caused by S. pneumoniae.
authors.affiliation: Pediatric Infectious Disease Unit, Soroka University Medical Center and the Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Arnon
authors.initials: A
authors.lastname: Broides
authors.forename: Eugene
authors.initials: E
authors.lastname: Leibovitz
authors.forename: Ron
authors.initials: R
authors.lastname: Dagan
authors.forename: Joseph
authors.initials: J
authors.lastname: Press
authors.forename: Simon
authors.initials: S
authors.lastname: Raiz
authors.forename: Michael
authors.initials: M
authors.lastname: Kafka
authors.forename: Alberto
authors.initials: A
authors.lastname: Leiberman
authors.forename: Tikva
authors.initials: T
authors.lastname: Yermiahu
mesh_terms: D000208:Acute Disease; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D002675:Child, Preschool; D004432:Ear, Middle / Q000166:cytology; D005260:Female; D006192:Haemophilus Infections / Q000150:complications; D006193:Haemophilus influenzae / Q000302:isolation & purification / Q000472:pathogenicity; D006801:Humans; D007223:Infant; D007962:Leukocytes; D008297:Male; D009504:Neutrophils; D010034:Otitis Media with Effusion / Q000097:blood / Q000188:drug therapy / Q000473:pathology*; D011008:Pneumococcal Infections / Q000150:complications; D013296:Streptococcus pneumoniae / Q000302:isolation & purification / Q000472:pathogenicity
chemical_list: D000900:Anti-Bacterial Agents