Comparison of pathogenic bacteria and drug sensitivity in neonates with pneumonia hospitalized in intensive care unit and common in-patient ward

Abstract

Objective The differences in pathogenic bacteria and their drug sensitivity in neonates with pneumonia were compared between: (1)neonates treated in NICU and stayed in common in-patient ward; (2)neonates treated with ventilator or without ventilator; (3)neonates supported by different mechanical ventilation mode. Methods The data of 222 neonates with pneumonia hospitalized in the Children's Hospital of Chongqing Medical University between Jul.2012 to Jan.2013 were analyzed retrospectively.Patients were divided into NICU group(n=152) and common in-patient ward group(n=70). Meanwhile, in NICU group, the neonates were divided into inspiration support group(n=90) and without inspiration support group(n=62). Moreover, in inspiration support group, the patients were further divided into invasive ventilation group who were treated by mechanical ventilation support(n=74), and noninvasive ventilation group who were only treated by CPAP(n=16). The differences in pathogenic bacteria and their drug sensitivity were compared among different groups. Results 1.The findings of pathogenic bacteria of sputum culture: the pathogens were mainly Gram-negative bacilli both in NICU group and common in-patient ward group, but the ratio of Gram-negative bacilli in NICU group was significantly higher than that of common in-patient ward group[92.6%(150/162 cases) vs 68.7%(44/64 cases), χ2=28.846, P=0.000]; the ratio of multidrug-resistant bacteria in NICU group was significantly higher than that in common in-patient ward group, [18.5%(30/162 cases) vs 0, χ2=13.666, P=0.000]. No difference in the ratio of Gram-negative bacilli was found between inspiration support group and without inspiration support group[91.6%(108/118 cases) vs 95.5%(42/44 cases), χ2=6.805, P=0.224]. There was no significant difference in the ratio of multidrug-resistant bacteria between groups with or without inspiration support[20.4%(24/118 cases) vs 19.0%(8/44 cases), χ2=0.095, P=0.826]. No significant difference in the ratio of Gram-negative bacilli was found between the invasive ventilation group and the noninvasive ventilation group[90.2%(92/102 cases) vs 100.0%(16/16 cases), χ2=3.552, P=0.169]. Escherichia coli, pseudomonas aeruginosa, acinetobacter bauman were the majority of multidrug resistant bacteria(drug-resistant rate was 66.0%-100.0%) in NICU group.2.Drug sensitivity results of sputum culture: the pseudomonas aeruginosa in the invasive ventilation group were resistant to conventional antibiotics, but sensitive to multiple stuck ring(drug-sensitive rate was 100.0%). Klebsiella pneumoniae subspecies, enterobacter cloacae had certain sensibility to imipenem and cilastatin sodium for injection use, merope-nem, amikacin(drug-sensitive rate was 60.0%-100.0%). Because of these Gram-negative bacilli derived from diffe-rent groups, even the same bacillus to the same antibiotics their drug-sensitive rate still had certain differences: the drug-sensitive rate of Gram-negative bacilli in NICU group was generally lower than that of common in-patient ward group; meanwhile, that in the inspiration support group was generally lower than that without inspiration support group; moreover, that in the invasive ventilation group was generally lower than that of noninvasive ventilation group.The major Gram-negative bacilli in the common in-patient ward group had almost resistance to cefazolin sodium and ampicillin mostly(drug-resistant rate were 100.0%), but had sensibility to some extent to piperacillin/tazobactam and ceftazidime(drug-sensitive rate were 50.0%-70.0%); which also had higher sensibility to amikacin, levofloxacin, meropenem, imipenem and cilastatin sodium for injection use(drug-sensitive rate was>70.0%). Conclusions The pathogens were mainly Gram-negative bacilli in neonates treated in NICU with pneumonia.The top five bacilli were klebsiella pneumo-niae subspecies, bauman acinetobacter, pseudomonas, enterobacter and escherichia coli.The neonates with pneumonia who were managed in NICU or treated with ventilator or supported by invasive ventilation might more easily infected by multidrug-resistant bacteria.Carbon penicillins, aminoglycoside antibiotics might be more effective during treating the neonates with pneumonia who are treated in NICU.The antibiotic containing enzyme inhibitor, or carbon penicillins, aminoglycosides and quinolones might be effective during treating the neonate with pneumonia who are managed in common in-patient ward. Key words: Pneumonia; Sputum culture; Pathogenic bacteria; Drug sensitive test; Newborn