Analysis Of Bacterial Culture And Antibiotics Susceptibility Test For Chronic Rhinosinusitis

Objective: To approach the characteristics of aerobes distribution in nasal cavity and antibiotics susceptibility in local patients with chronic rhinosinusitis(CRS)by nasal bacterial culture and antibiotics susceptibility test for these patients,in an attempt to provide evidence for rational clinical selection of antibiotics in the local region.Methods: Between January 1st,2010 and December 31 st,2015,nasal bacterial culture and antibiotics susceptibility test were performed on 181 selected local patients with CRS randomly.Specimens were collected before the use of antibiotics and routine disinfection of nasal vestibule and skin around the nose was conducted.Under the assistant of sterile anterior rhinoscope or nasal endoscope,sterile sampling swabs were placed into the middle nasal meatus and made full contact and wipe with the mucosa and nasal polyp tissue at the swelling site of the middle nasal meatus.The swabs were rotated to retain and collect the sticky purulent secretions,and the specimens were sent to a clinical test center within one hour to conduct isolation and culture of aerobic bacteria and antibiotics sensitivity test.The clinical rational use of antibiotics was guided based on the antibiotics sensitivity reports.Patients were classified into elderly CRS patient group,young and middle-aged CRS patient group and nonage CRS patient group according to age characteristics.Chi-square test was used to compare the positive rate differences of the aerobic bacteriumculture reportsbetween the elderly CRS patient groupand the young and middle-aged CRS patient group.Results: Among the 181 cases of specimens,one case was shown to have no bacterium growth in two days’ culture,while all the other 180 cases(99.4%,180/181)were found to have the growth of Streptococcus viridans,Neisseria,Grampositive bacillus and other normal microbes present in the upper respiratory tract,which is not within the report scope of the clinical test centers.18 strains and 11 species of aerobic bacteria with a positive rate of 9.9%(18/181)were reported by the clinical test center.10 strains(5.5%,10/181)of the aerobic bacteria belonged to Gram positive aerobes,among which Staphylococcus aureus was the most common bacterial strain(3.3%,6/181).The other 8 strains(4.4%,8/181)of the aerobic bacteria belonged to Gram negative aerobes,among which Enterobacter aerogenes was the most common strain(1.7%,3/181),and all the other strains distributed evenly.The elderly CRS patient group had 30 cases of specimens,and the positive rate was reported to be 16.7%(5/30).All the 5 strains of aerobic bacteria belonged to Gram positive aerobes,among which the Staphylococcus aureus had the highest ratio of 60%(3/5),and the others were Streptococcus pneumoniae and group A β-hemolytic streptococci having one strain for each.The young and middle-aged CRS patient group had 139 cases of specimens,and the positive rate was reported to be 9.4%(13/139),among which 5 strains belonged to the Gram positive aerobes,and the remaining 8 strains belonged to the Gram negative aerobes,and the Staphylococcus aureus and the Enterobacter aerogenes were the most common bacterial strains.All the specimens from the nonage CRS patient group were found to have only the normal microbes present in the upper respiratory tract and had no positive reports from the clinical test center.By conducting chi-square tests,the reported positive rate differences between the elderly CRS patient group and the young and middle-aged CRS patient group had no statistical significance(χ2 = 1.387,P = 0.239,P> 0.05).The results of the drug sensitivity test indicated that the young and middle-aged CRS patient group had one strain of Methicillin resistant Staphylococcus epidermidis(MRSE)and one strain of the third-generation cephalosporins resistant Gram negative bacillus.And the young and middle-aged CRS patient group and the elderly CRS patient group each had one strain of the Methicillin resistant Staphylococcus aureus(MRSA).MRSA accounted for 33.3%(2/6)of the total Staphylococcus aureus.The three strains of Methicillin resistant Staphylococcus(MRS)were all sensitive to levofloxacin,dalfopristin,linezolid and vancomycin.As a whole,ampicillin,penicillin and amoxicillin-clavulanic acid all had wide antibiotic resistance,while vancomycin and the fourth-generation cephalosporins were not found to have any antibiotic resistance.Conclusion: The aerobes from nasal cavity of CRS patients were mainly normal flora of the upper respiratory tract,and the bacterial strains were extensive.Staphylococcus aureus and Enterobacter aerogenes to be the most common and the remaining bacterial strains to be homogenously distributed.Antibiotics susceptibility test showed high resistance rates to ampicillin,penicillin and amoxicillin-clavulanate.Levofloxacin was good in activity to aerobes.MRS and the third-generation cephalosporins resistant Gramnegative bacillus are present in the nasal cavity of a small proportion of CRS patients in the local region,therefore,it is necessary to reinforce the monitoring,prevention and control of nosocomial infection.