[Analysis of the changes of bacterial spectrum and drug resistance in sputum culture of ICU children in a hospital of pediatric in Jiangsu Province from 2017 to 2022].

<b>Objective:</b> To investigate the changes of the distribution and drug resistance profile of bacteria from ICU children with lower respiratory tract infection (LRTI) in Suzhou City, Jiangsu Province from 2017 to 2022. <b>Methods:</b> From January 2017 to December 2022, a cross-sectional observational study on the bacterial spectrum analysis among intensive care unit (ICU) children with LRTI was conducted in Children's Hospital of Soochow University. The bacteria was cultivated by culture methods from sputum samples, and identified by MALDI-TOF mass spectrometry. Drug sensitivity tests were performed by the VITEK2 Compact fully automated analysis system and the paper slide method. The <i>χ</i>² test or Fisher's exact probability was used to analyze the changes of the distribution of sputum culture-positive bacteria and drug resistance in ICU children. <b>Results:</b> The overall detection rate of sputum culture was 42.06% (1 182/2 810). <i>Staphylococcus aureus</i> (25.63%,303/1 182), <i>Acinetobacter baumannii</i> (13.62%,161/1 182) and <i>Haemaphilus influenzae</i> (13.28%,157/1 182) were the top three. Proportions of <i>Acinetobacter baumannii</i> (17.90% <i>vs.</i> 11.02%,<i>χ</i>²=11.17, <i>P</i>=0.001), especially carbapenem-resistant <i>Acinetobacter baumannii</i> (43.70% <i>vs.</i> 23.50%, <i>χ²</i>=15.21, <i>P</i><0.001) increased significantly from 2020 to 2022. However, the proportions of <i>Haemophilus influenzae</i> (8.50% <i>vs.</i> 16.19%, <i>χ</i>²=14.27, <i>P</i><0.001), <i>Streptococcus pneumoniae</i> (8.50% <i>vs.</i> 15.92%, <i>χ</i>²=13.42, <i>P</i><0.001) and extended-spectrum-lactamase producing <i>Escherichia coli</i> (8.89% <i>vs.</i> 18.00%, <i>χ</i>²=5.45, <i>P</i>=0.025) decreased. Drug resistant results showed that <i>Acinetobacter baumannii</i> was obviously more resistant to imipenem (<i>χ²</i>=4.43, <i>P</i>=0.035) and levofloxacin (<i>χ</i>²=12.53, <i>P</i><0.001), while more sensitive to minocycline (<i>χ</i>²=8.34, <i>P</i>=0.004). Escherichia coli showed a significant increase in resistance to piperacillin tazobactam (<i>χ</i>²=8.29, <i>P</i>=0.008) and cefoperazone sulbactam (<i>χ</i>²=5.07, <i>P</i>=0.024) from 2020 to 2022; Klebsiella pneumoniae consistently maintained a resistance rate of more than 60% to first and second-generation cephalosporins, and remain susceptible to quinolones and carbapenems. Staphylococcus aureus remained highly susceptible to levofloxacin (drug resistance rate: 2.31%,7/303) and sulfamethoxazole/trimethoprim (drug resistance rate: 4.95%,15/303) from 2020 to 2022. <b>Conclusion:</b> Higher detection and resistance rates of <i>Acinetobacter baumannii</i> from sputum culture in ICU children from 2020 to 2022 were explored. Resistance of <i>Escherichia coli</i> to β-lactamase inhibitor combinations was more serious. Regular monitoring the changes of the etiology of respiratory tract infections in ICU Children is particularly important for the prevention and treatment of multidrug-resistant bacterial infections.