Surveillance Of Drug Resistance And Clinical Characteristics Of Pathogens In Nosocomial Infection In A Hospital(in Guangzhou)

Objective The aim of this study was to analyze the distribution,drug resistance,related clinical characteristics of pathogens in nosocomial infection(NI)in the First Affiliated Hospital of Jinan University from January 1,2016 to July 31,2019.Methods Based on the Diagnostic Standards for Nosocomial Infection(Trial)issued by the Ministry of Health in 2001,289 pathogenic bacteria were included in the study from January 1,2016 to July 31,2019.The distribution,classification and drug resistance of pathogenic bacteria were analyzed.According to the type of pathogens,they were divided into Gram-positive cocci,Gram-negative bacilli and fungus.The clinical data of basic condition,history of underlying diseases,history of invasive operation and related test results were collected in order to compare the clinical characteristics of these three groups.Results The results showed that Gram-negative bacilli accounted for 74.05%of 289 pathogens in NI.Gram-positive cocci accounted for 16.96%and fungus accounted for 8.30%.Among Gram-positive cocci,Multidrug-resistant organisms(MRDOs)accounted for 55.10%and MDROs accounted for 54.21%of Gram-negative bacilli.There was no statistical difference between these two groups(χ~2=0.013,P>0.05).The common pathogens in NI were 95 strains of Acinetobacter baumannii(ABA)(32.87%),40 strains of Klebsiella pneumoniae(KPN)(13.84%),34 strains of Pseudomonas aeruginosa(PAE)(11.76%),18 strains of Escherichia coli(E.coli)(6.23%),11 strains of MRSA(3.81%),10 strains of Candida albicans(3.46%).ABA and PAE tended to increase first and then decrease.The incidence rates of KPN and MRSA gradually increased,and KPN became the first pathogenic bacteria in 2019.E.coli and Candida albicans remained relatively stable.There were differences in the distribution of pathogens in NI in the nearly four years(P<0.05).The main source of specimen was lower respiratory sputum,which accounted for 48.79%,and increased in the first three years.The next were blood and urine,which accounted for 21.45%and 14.19%.The specimen of blood decreased firstly and then increased,while urine showed no significant fluctuation.There were statistically significant differences in the specimen distribution of pathogens in NI over the nearly four years(P<0.05).The departments of ICU,neurosurgery,respiratory internal medicine and hematology were the four severe units that detected pathogens in NI,accounting for 25.53%,22.49%,12.80%,and9.34%,respectively.ICU had detected the most ABA for nearly four consecutive years.KPN was mainly distributed in neonatology,ICU and neurosurgery units.PAE was mainly distributed in the units of neurosurgery and respiratory internal medicine.In drug susceptibility analysis,ABA had the lowest resistance rate to tigecycline and polymyxin,both being only 2.27%.It was highly resistant to aminoglycosides,penicillin/β-lactamase inhibitors,and cephalosporins.The resistance rate of KPN to amikacinis was 28.57%,and to tigecycline 5.00%.The resistance rates to imipenem and meropenem were about 50.00%,52.50%,respectively.PAE had low resistance to aminoglycosides.The resistance rate of PAE to polymyxin was 8.33%,and to first-,second-and third-generation cephalosporins was above 90.00%.The resistance rates of some third-generation cephalosporins(ceftazidime,cefoperazone)and fourth-generation cephalosporins(Cefepime)were between 13.33%and 30.30%.Gram-positive cocci and Gram-negative bacilli were significantly different in the lung(28.89%vs 58.54%,P<0.001)and skin/mucosa(15.56%vs 3.41%,P<0.05).There were significant differences in the composition of the lung(28.89%vs 25.00%,P<0.05)and urine(13.33%vs 62.50%,P<0.001)between the Gram-negative bacilli and the fungus,while the urine between the fungus and Gram-positive cocci were significantly different(P<0.001).There were significant differences in sex,lumbar puncture,tracheotomy,and whether to live in ICU in the three groups of Gram-negative bacilli,Gram-positive cocci,and fungus(P<0.05).Conclusion 1.Gram-negative bacilli were main pathogens in our hospital,mainly including ABA,KPN and PAE.2.Lower respiratory sputum,blood,and urine were the main specimen for pathogens in NI,while ICU,neurosurgery,respiratory internal medicine and hematology units became the main departments for the distribution of pathogens in NI in our hospital.3.According to the serious situation of multidrug resistance,they were in a descending order followed by ABA,KPN and PAE.4.Gram-negative bacilli were more likely to occur in lung infection.Gram-positive cocci were more likely to occur in skin/mucosal infection and fungus was more likely to occur in urinary tract infection.