Microbiological efficacy of 3-day treatment with azithromycin 1.5% eye-drops for purulent bacterial conjunctivitis.
OBJECTIVE
Antibacterial efficacy of topically applied azithromycin 1.5% was compared with tobramycin 0.3% in a multicenter, randomized, investigator-masked study for the treatment of purulent bacterial conjunctivitis.


METHODS
A total of 1043 adults and children received either azithromycin twice daily for 3 days (n=524) or tobramycin every 2 hours while awake for 2 days, then four times daily for 5 days (n=519). Conjunctival swabbing was taken at days 0, 3, and 9, using alginate swabs resuspended in a dissolution-transport medium, providing rapid and reproducible results. Cagle's criteria were used to define the pathogenicity level for each isolated bacterium.


RESULTS
In the per-protocol set, the rate of bacteriologic resolution was 85.2% for azithromycin versus 83.8% for tobramycin on day 3, and 92.8% for azithromycin versus 94.6% for tobramycin on day 9. Azithromycin was demonstrated to be noninferior to tobramycin according to the 10% noninferiority margin. Although some bacteria were categorized as resistant to tested antibiotics, eradication was observed (for azithromycin: Acinetobacter, Enterobacteriaceae, Pseudomonas), highlighting the specific pharmacokinetics/pharmacodynamics of the ocular route.


CONCLUSIONS
In total, topical therapy with azithromycin 1.5% administered only twice daily for 3 days effectively eradicates most pathogenic bacteria associated with bacterial conjunctivitis. These microbiologic results are in accordance with the observed clinical outcome. This new anti-infective product has the advantage of a short treatment course which could lead to an improvement in patient compliance.
Denis
F
F
Service de Bactériologie-Virologie-Hygiène, CHU de Limoges, Limoges Cedex - France. francois.denis@unilim.fr
Chaumeil
C
C
Goldschmidt
P
P
Delval
L
L
Pouliquen
P
P
Cochereau
I
I
Chainier
D
D
De Barbeyrac
B
B
D000287:Administration, Topical; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000627:therapeutic use; D017963:Azithromycin / Q000008:administration & dosage* / Q000627:therapeutic use; D001419:Bacteria / Q000187:drug effects / Q000302:isolation & purification; D002648:Child; D002675:Child, Preschool; D003228:Conjunctiva / Q000382:microbiology; D003234:Conjunctivitis, Bacterial / Q000188:drug therapy* / Q000382:microbiology; D004311:Double-Blind Method; D024881:Drug Resistance, Bacterial; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D009883:Ophthalmic Solutions / Q000008:administration & dosage / Q000627:therapeutic use; D013997:Time Factors; D014031:Tobramycin / Q000008:administration & dosage* / Q000627:therapeutic use; D055815:Young Adult
D000900:Anti-Bacterial Agents; D009883:Ophthalmic Solutions; D017963:Azithromycin; D014031:Tobramycin