The effect of treatment with moxifloxacin or azithromycin on acute bacterial rhinosinusitis in mice.
OBJECTIVE
Acute bacterial rhinosinusitis, which is a major health problem, is treated with antibiotics. We developed a mouse model of acute bacterial rhinosinusitis to gain a better understanding of the pathophysiology of the disease. Our goal was to investigate the response to acute rhinosinusitis when treated with either a bactericidal or a bacteriostatic antibiotic.


METHODS
C57BL/6 mice were infected intranasally with Streptococcus pneumoniae. One day after inoculation, the mice were treated with either moxifloxacin (bactericidal) or azithromycin (bacteriostatic). Different groups were euthanized during the first five days post-inoculation. Bacterial counts from nasal lavage culture and the cell markers GR1, CD11b, CD3, CD4, and CD8 in sinus tissue were evaluated by flow cytometry.


RESULTS
Azithromycin led to rapid clearance of the bacteria and of the inflammation in contrast to placebo. Surprisingly, moxifloxacin showed a limited effect. Investigations of this limited effect of moxifloxacin suggested a high metabolic clearance, a low concentration at the site of infection, and low persistent post-antibiotic effects of moxifloxacin in mice.


CONCLUSIONS
Our animal model of acute sinusitis has great utility for studying the disease, but the difference between mice and man must always be considered in making extrapolations from animal experiments to the human experience.
Luxameechanporn
Thongchai
T
Section of Otolaryngology-Head and Neck Surgery, University of Chicago, 5841 South Maryland Avenue, MC 1035, Chicago, IL 60637, USA.
Blair
Christopher
C
Kirtsreesakul
Virat
V
Thompson
Kenneth
K
Naclerio
Robert M
RM
D000208:Acute Disease; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001372:Aza Compounds / Q000494:pharmacology*; D017963:Azithromycin / Q000494:pharmacology*; D039481:CD11b Antigen / Q000276:immunology; D015704:CD4 Antigens / Q000276:immunology; D016827:CD8 Antigens / Q000276:immunology; D004195:Disease Models, Animal; D005260:Female; D024841:Fluoroquinolones; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D000077266:Moxifloxacin; D011008:Pneumococcal Infections / Q000188:drug therapy* / Q000276:immunology / Q000382:microbiology; D011804:Quinolines / Q000494:pharmacology*; D012220:Rhinitis / Q000188:drug therapy* / Q000276:immunology / Q000382:microbiology; D012852:Sinusitis / Q000188:drug therapy* / Q000276:immunology / Q000382:microbiology; D013296:Streptococcus pneumoniae / Q000302:isolation & purification*
D000900:Anti-Bacterial Agents; D001372:Aza Compounds; D039481:CD11b Antigen; D015704:CD4 Antigens; D016827:CD8 Antigens; D024841:Fluoroquinolones; D011804:Quinolines; D017963:Azithromycin; D000077266:Moxifloxacin