Bacteriological Study Of Chronic Maxillary Sinusitis And Posterior Ethmoid Sinusitis In Adults

Objective: To provide a theoretical instruction for selecting antibiotics properly and improving its cure rate of chronic sinusitis in adults, the research of its bacteriological character and the susceptibility to antibiotics of bacteria were performed. Meanwhile, the potential role of fungi in the pathogenesis of chronic sinusitis was explode.Methods: The purulent discharges taken from the maxillary sinus and posterior ethmoid sinus of 37 patients during endoscopic sinus surgery were cultured for the growth of aerobes, anaerobes and fungi and then the microorganism isolated were identificated. On the basis of the above, the antimicrobial susceptibility testing of aerobes and anaerobes were respectively determined by disc agar diffusion method and epsilometer test; The β-lactamase-producing bacteria (βLPB) was detected by iodine. Of healthy control group, the discharges taken from 10 adults'nose by swab were also cultured for the growth of aerobes, anaerobes and fungi.Results: Of the testing group, 39 strains, including 30 aerobes, 8 anaerobes and 1 Candida albicans, were cultured from 37 samples of the maxillary sinus; 38 strains, including 27 aerobes, 7 anaerobes and 1 aspergillus, were cultured from 34 samples of the posteroir ethmoid sinus. The strains from testing group presented widely, including 20 species of many genuses of bacteria. Of aerobes, the most frequently isolated bacteria, in descending order, were Staphylococcus epidermidis, Colibacillus, a-Hemolytic streptococcus and Staphylococcus aureus. Of anaerobes,3the most frequently isolated bacteria, in descending order, were Peptostreptococcus and Bacteroides fragilis. Of the control group, 9 strains, including 3 Staphylococcus epidermidis, 2α-Hemolytic streptococcus, 1 Escherichia coli, 1 Pseudomonas aeruginosa, 1 Branhamella catarrhalis and 1 Bacteroides fragilis (anaerobe), were found in 9 samples. For the same bacteria, statisticly, there was no significant difference of distribution between control group and sinusitis group (P>0.05) and the same with all the bacterial distribution between maxillary sinus and posterior ethmoid sinus (P>0.05). The total culture rate of aerobes, anaerobes and fungi from testing group was respectively 76.06%, 25.35% and 2.82%; the bataLPB were found in 41.33 per cent of strains. The antimicrobial susceptibility testing showed that Vancomycin, Imipenem, Cefetaxime and Amoxicillin-clavulanate were effective to gram positive aerobe and that Imipenem, Cefetaxime, Amoxicillin-clavulanate and Azthreonam to gram negative aerobe and thatMetronidazole, Chloramphenical, Imipenem and Cillimycin to anaerobes.Conclusion: Bacteriology of chronic sinusitis in adults involved many mixed aerobic and anaerobic growth and most of bacteria were aerobes. The strains presented widely, but more of them were normal flora and non-pathogenicity bacteria whose resistance to many antibiotics was serious. The bacterial infection played a little role in the pathogenesis of chronic sinusitis, but the role of fungi have to be estimated by further investigations. As for treating, culture of bacteria and antimicrobial susceptibility testing should been performed first, so antibiotics can been properly choosed according to the character of pathomicroorganism and the outcome of test. If impossible for finishing the test, broad-spectrum antibiotics containing p-lactamase inhibitor that were both susceptible to aerobes and to anaerobes were recommended, or two antibiotics, one of which was susceptible to aerobes and the other to anaerobes, can been selected for a united use.