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Updated: Jul 13, 2026

Conjunctival Commensal Isolation and Identification in Mice
Published on: May 1, 2021
Comparison of azithromycin and moxifloxacin against bacterial isolates causing conjunctivitis
Christina Ohnsman1, David Ritterband, Terrence O'Brien
1Wills Eye Institute, Philadelphia, PA, USA. cohnsman@comcast.net
Objective:
To examine in vitro resistance to azithromycin and moxifloxacin in bacterial conjunctivitis isolates.
Methods:
MIC90s (Minimum Inhibitory Concentration) and resistance rates to azithromycin and moxifloxacin were determined based upon microtiter broth dilution and/or antimicrobial gradient test strips in a multicenter phase III study and confirmed externally.
Results:
The most common isolates collected from bacterial conjunctivitis patients in the phase III study were Haemophilus influenzae (40.6%), followed by Staphylococcus epidermidis (19.3%), Propionibacterium acnes (17.3%), Streptococcus pneumoniae (16.8%), and Staphylococcus aureus (0.06%). MIC90s for all of these organisms were well below established resistance breakpoints for moxifloxacin, indicating no bacterial resistance. On the other hand, the MIC90 for H. influenzae was 3-fold higher than the resistance breakpoint for azithromycin, > or = 128-fold higher for S. epidermidis, 16-fold higher for S. pneumoniae and > or = 128-fold higher for S. aureus, indicating moderate to very high bacterial resistance to azithromycin.
Conclusions:
Resistance to azithromycin is more common than resistance to moxifloxacin in clinical isolates causing bacterial conjunctivitis.
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Acute Pharyngitis
Acute pharyngitis is the inflammation of the back of the throat (pharynx), commonly resulting in a sore throat. It is a frequently encountered condition that prompts individuals to seek medical advice.
Classification
Acute pharyngitis can be categorized based on its underlying cause:
Antibiotic Selection

