Persistence of pathogens despite clinical improvement in antibiotic-treated acute otitis media is associated with clinical and bacteriologic relapse.
BACKGROUND
Pathogen eradication in patients with acute otitis media (AOM) is associated with a reduced risk of clinical failures, but most children in whom middle ear fluid (MEF) culture remains positive show clinical improvement or clinical cure. We investigated the relationship between MEF culture-positivity during treatment in patients with clinical improvement/cure, and the occurrence of subsequent AOM.


METHODS
A total of 673 patients with culture-positive MEF were enrolled in double-tympanocentesis studies and followed for 3 weeks after completion of treatment.


RESULTS
On day 4-6, 189/673 (28%) patients had culture-positive MEFs. Patients with clinical improvement/cure on day 11-14 (end of treatment) despite having culture-positive MEF on day 4-6 more often had recurrent AOM episodes (53/151, 35%) than those with culture-negative MEF (114/476, 24%; P = 0.007). 41/53 (77%) culture-positive patients with clinical improvement/cure on day 11-14 underwent tympanocentesis when AOM recurred and 29/41 (71%) were culture-positive. Pulsed field gel electrophoresis identity between pathogens at recurrence and those persisting on day 4-6 was found in 19/29 (66%) compared with 31/86 (36%) of the evaluable patients with recurrence and culture-negative MEF on day 4-6 (P = 0.005).


CONCLUSIONS
(1) Failure to eradicate MEF pathogens during antibiotic treatment is associated with clinical recurrences, even in patients showing clinical improvement/cure at end of treatment; (2) these recurrences are mostly caused by pathogens initially present in MEF and persisting during treatment.
Asher
Elad
E
Pediatric Infectious Disease Unit, Soroka University Medical Center and the Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
Dagan
Ron
R
Greenberg
David
D
Givon-Lavi
Noga
N
Libson
Shai
S
Porat
Nurith
N
Leiberman
Alberto
A
Leibovitz
Eugene
E
D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D001419:Bacteria / Q000145:classification / Q000302:isolation & purification*; D015373:Bacterial Typing Techniques; D002675:Child, Preschool; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000235:genetics; D004432:Ear, Middle / Q000382:microbiology; D016521:Electrophoresis, Gel, Pulsed-Field; D005260:Female; D005838:Genotype; D006801:Humans; D007223:Infant; D008297:Male; D010033:Otitis Media / Q000188:drug therapy* / Q000382:microbiology* / Q000503:physiopathology; D019152:Paracentesis; D012008:Recurrence
D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial