[Tympanostomy tube otorrhea: microbiological epidemiology, pathogen susceptibility to local antibiotics and bactericidal power of the rifamycin-olfloxacin combination].
OBJECTIVE
We studied the microbiological epidemiology of tympanostomy tube otorrhea, rifamycin and ofloxacin sensitivity of pathogens isolated from these otorrheas, and the bactericidal power of the rifamycine-ofloxacin combination.


METHODS
A prospective study was conducted in 1997 with cultures of otorrhea aspirates, in vitro study of pathogen resistance to rifamycin and ofloxacin, bacteriocidal study of the rifamycin-ofloxacin combination.


RESULTS
One hundred eight aspirates were obtained from 98 children (mean age 5 years). Ten aspirates were sterile, 32 had more than one pathogen. The more frequent pathogens were Pseudomonas aeruginosa (Pa) (n=35), Staphylococcus aureus (Sa) (n=27), Haemophilus influenae (Hi) (n=12) and Streptococcus pneumoniae (Sp) (n=9). All Hi, all Sp, 86.3% of the Sa (MIC(90) 0.25 mg/l) and none of the Pa were rifamycin sensitive. All Hi, 97.7% of the Pa (MIC(90) 0.5 mg/l), 73,1% of the Sa (MIC(90) 0.24 mg/l) and none of the Sp were ofloxacin sensitive. The rifamycin-ofloxacin combination led to a 4 log CFU/ml decrease in 6 hours for Sp, and in 24 hours for Pa, Hi and Sa.


CONCLUSIONS
The rifamycin-ofloxacin combination is bactericidal for bacteria causing tympanostomy tube otorrhea. Otic drops with this combination should be considered as the first line treatment for such otorrhea.
François
M
M
Service ORL du Pr Narcy, hôpital Robert Debré, Faculté Xavier Bichat, 48 bd Sérurier, 75019 Paris, France.
Mariani-Kurkdjian
P
P
Doit
C
C
Benzekri
P
P
Bingen
E
E
Macé
J G
JG
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000890:Anti-Infective Agents / Q000494:pharmacology*; D002675:Child, Preschool; D004359:Drug Therapy, Combination / Q000494:pharmacology*; D005260:Female; D006193:Haemophilus influenzae / Q000187:drug effects; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008876:Middle Ear Ventilation / Q000009:adverse effects*; D015242:Ofloxacin / Q000494:pharmacology*; D010034:Otitis Media with Effusion / Q000382:microbiology*; D011446:Prospective Studies; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D012294:Rifamycins / Q000494:pharmacology*; D013211:Staphylococcus aureus / Q000187:drug effects; D013296:Streptococcus pneumoniae / Q000187:drug effects
D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; D012294:Rifamycins; D015242:Ofloxacin