Abstract:

Objective To analyze the epidemiological characteristics of otitis media infection in children in Suzhou, distribution of pathogenic bacteria and change in the drug resistance rate. Methods Children with otitis media from the Department of Otolaryngology, Children's Hospital of Soochow University for 9 consecutive years from January 2012 to December 2020 were collected, the bacterial culture was implemented on the pus secretion from children's middle ear, the distributions of primary pathogenic bacteria in different seasons and age groups, and the characteristics of change in drug resistance rate of such children were dynamically analyzed. Results A total of 970 pathogenic bacteria were isolated from the middle ear pus secretions of 1 312 children with an overall positive rate of 73.9%. Common pathogens were Streptococcus pneumoniae, Staphylococcus aureus and Haemophilus influenzae, the positive rate of which were 31.7%, 23.1% and 4.4%, respectively during the period from 2012 to 2014, the positive rate of such indexes during the period from 2015 to 2017 was 32.7%, 30.4% and 4.5%, respectively, and the positive rate of such indexes during the period from 2018 to 2020 was 28.5%, 24.7% and 5.5%, respectively. The positive rate of Staphylococcus aureus during the period from 2015 to 2017 was higher than that during the period from 2012 to 2014 and such period from 2018 to 2020 (all P<0.05); the difference in the positive rate of Streptococcus pneumoniae and Haemophilus influenzae during the time periods wasn't statistically significant (all P>0.05). The positive rate of methicillin-resistant Staphylococcus aureus (MRSA) in ear pus secretions during the periods from 2012 to 2014, from 2015 to 2017 and from 2018 to 2020 was 30.8%, 27.2% and 46.2%, respectively; the detectable rate of MRSA during the period from 2018 to 2020 was higher than that during the periods from 2015 to 2017 and from 2012 to 2014(all P<0.05). The detectable rate of Streptococcus pneumoniae in subjects from different age groups varied, and the detectable rate of Streptococcus pneumoniae in subjects >5 years old was the minimum (all P<0.05). The detectable rate of Staphylococcus aureus in subjects from different age groups varied, and the detectable rate of Staphylococcus aureus in subjects >5 years old and ≤6 months was higher (all P<0.05); the detectable rate of Haemophilus influenzae in subjects from different age groups varied, and the detectable rate was maximum in the subject from the age group >5 years old (all P<0.05). The detectable rate of Streptococcus pneumoniae varied in different seasons, and the detectable rate in summer was minimum; the detectable rate of Staphylococcus aureus in different seasons varied, and the detectable rate was higher in spring and summer, accounting for 39.6% and 45.5% respectively; the detectable rate of Haemophilus influenzae varied in different seasons, the detectable rate in spring and autumn was the maximum or minimum, respectively. Streptococcus pneumoniae was not found to be resistant to vancomycin and levofloxacin, and it was highly resistant to erythromycin and co-trimoxazole, and the drug resistance rate was greater than 93.5%; the resistance rate of Streptococcus pneumoniae to penicillin varied during the period from 2012 to 2020 was statistically significant (P<0.05), the drug resistance rate during the periods from 2012 to 2014, 2015 to 2017 and 2018 to 2020 were 51.4%, 29.5% and 25.3%, respectively; the resistance rate to quinupristin from 2012 to 2020 showed an upward trend (P<0.05), the drug resistance rate during the periods from 2012 to 2014, from 2015 to 2017 and from 2018 and 2020 was 60.7%, 77.4% and 86.7%, respectively. Staphylococcus aureus was highly sensitive to vancomycin and rifampicin, and no vancomycin-resistant strains were found; the resistance rate to ciprofloxacin, levofloxacin and moxifloxacin during different time periods varied (all P<0.05), all drug resistance rates during the period from 2015 to 2017 was the maximum; while the drug resistance rate for oxacillin and cefoxitin showed an upward trend (all P<0.05). Conclusion Streptococcus pneumoniae, Staphylococcus aureus and Haemophilus influenzae are main pathogens of otitis media in children in Suzhou. The detectable rate of such bacteria shows significant seasonal changes. The detectable rate of MRSA and drug resistance rate of Streptococcus pneumoniae significantly increase. Antibiotics should be used reasonably and standardized in clinical services.

Key words: otitis media, bacteria, child