目的:了解本地区小儿败血症的病原菌种类、不同病原菌在各年龄段的分布情况及主要病原菌药物敏感状况,为指导临床诊断及合理使用抗生素提供依据。方法:对本院儿科近3年经血培养分离出的310株阳性菌株的构成比及对抗生素的药物敏感状况进行回顾性分析。结果:310株检出菌中G+菌201株占64.8%;G杆菌106株占34.2%;前5位病原菌依次为凝固酶阴性葡萄球菌(CNS)、沙门菌、大肠埃希菌、金黄色葡萄球菌(简称金葡菌)、链球菌属,分别占40.97%、21.61%、6.45%、4.51%、4.19%;新生儿败血症病原菌以CNS为主 (101株),其次为大肠埃希菌、肠球菌、克雷伯氏菌;6个月内小婴儿败血症致病菌与新生儿近似;婴幼儿各种细菌败血症均有发生;学龄前及学龄期儿童败血症病原菌依次为沙门菌、链球菌、金葡菌;药敏结果显示,大多数G+菌对青霉素、红霉素、苯唑西林、氨苄西林、头孢唑啉、头孢他啶、复方新诺明、庆大霉素耐药率超过60%;对万古霉素、利福平、阿米卡星、头孢西丁、喹诺酮类敏感。G杆菌中沙门菌对亚胺培南、氨曲南、三代头孢菌素、酶抑制剂复方制剂、喹诺酮类、复方新诺明保持高度敏感;大肠埃希菌多重耐药,对氨苄西林、哌拉西林、复方新诺明耐药率超过80%,对氨曲南、环丙沙星、庆大霉素、妥布霉素、头孢吡肟、头孢噻肟耐药率超过50%;其他G杆菌大多数对亚胺培南、呋南妥因、阿米卡星、奎诺酮类、头孢西丁敏感,酶抑制复合制剂的敏感率明显提高。结论:(1)CNS是新生儿及小婴儿败血症的主要病原菌,低毒力条件致病菌在该阶段小儿中感染率高;沙门菌是本地区近三年学龄期儿童败血症的主要病原菌,其感染呈逐年下降趋势。(2)不同病原菌的药敏状况差异很大,应高度重视感染病例的病原学检查,以利于制定临床抗感染方案,合理使用抗生素。(3)万古霉素、利福平、亚胺培南、氨曲南、第3代头孢菌素、阿米卡星及喹诺酮类目前仍为敏感抗生素。
Objective To investigate the pathogen distribution and drug resistance in ICU patients, provide reference for prevention of severe infection and empirical antibacterial treatment. Methods The patients admitted in ICU between January 2013 and December 2014 were retrospectively analyzed. The pathogenic data were collected including bacterial and fungal culture results, the flora distribution and drug resistance of pathogenic bacteria. Results A total of 2088 non-repeated strains were isolated, including 1403 (67.2%) strains of Gram-positive bacteria, 496 (23.8%) strains of Gram-negative bacteria, and 189 (9.0%) strains of fungus. There were 1324 (63.42%) strains isolated from sputum or other respiratory specimens, 487 (23.33%) strains from blood specimens, 277 (13.27%) strains from other specimens. The bacteria included Acinetobacter baumannii (17.2%), Klebsiella pneumoniae (14.8%), Pseudomonas aeruginosa (9.9%), C. albicans (6.3%), E. coli (5.6%), E. cloacae (5.4%), Epidermis staphylococcus (5.0%) and Staphylococcus aureus (4.7%). There were 15 strains of penicillium carbon resistant enterobacteriaceae bacteria (CRE) accounting for 2.3%, including 5 strains of Pneumonia klebsiella, 4 strains of E. cloacae. In 117 strains of E. coli, drug-resistant strains accounted for 86.4% including 85.5% of multiple drug-resistant strains (MDR) and 0.9% of extremely-drug resistant (XDR) strains. In 359 strains of Acinetobacter baumannii, drug-resistant strains accounted for 75.2% including 72.1% of XDR strains and 3.1% of MDR strains. MDR strains accounted for 10.6% in Pseudomonas aeruginosa. Detection rate of methicillin resistant Staphylococcus aureus (MRSA) and methicillin resistant coagulase-negative Staphylococci (MRCNS) was 49.0% and 95.5%, respectively. There were 4 strains of vancomycin resistant Enterococcus faecalis. There were 131 (69.3%) strains of C. albicans, 23 (12.2%) strains of smooth candida. C. albicans was sensitive to amphotericin and 5-fluorine cytosine, and the resistance rate was less than 1% to other antifungle agents. The resistance rate of smooth ball candida was higher than C. albicans and nearly smooth candida, but still less than 15%. Conclusions The predominant pathogens in ICU was gram-negative bacteria. The top eight pathogenic bacteria were Acinetobacter baumanni, Klebsiella pneumoniae, Pseudomonas aeruginosa, C. albicans, E. coli, E. cloacae, Epidermis staphylococcus and S. aureus. Sputum and blood are common specimens. CRE accounts for 2.3%. Drug-resistant strains are most common in E. coli mainly by MDR, followed by Acinetobacter baumannii mainly by XDR, and least in Pseudomonas aeruginosa. C. albicans is the most common fungus with low drug resitance.
ObjectiveTo detect the in vitro susceptibility of common clinical multidrug-resistant bacteria to tigecycline by disk diffusion (KB), minimum inhibitory concentrations (MIC) test strip (MTS) and Vitek 2 Compact methods, in order to evaluate the accuracy of the three different susceptibility testing methods. MethodsA total of 140 multidrug-resistant isolates (excluding Pseudomonas aeruginosa) were collected retrospectively from West China Hospital between January 2014 and March 2015. The inhibitory zone diameters and MIC of tigecycline were determined by KB, Vitek 2 Compact system and MTS respectively. The results of Vitek 2 Compact system and KB method were compared with that of MTS. ResultsAmong the 140 multidrug-resistant isolates, 119 were Acinetobacter baumannii, and 21 were Enterobacteriaceae. According to the US Food and Drug Administration standards, the sensitivity rates of 119 Acinetobacter baumannii isolates to tigecycline were 88.2%, 85.7%, and 90.8% respectively for KB method, Vitek 2 Compact system and MTS, and those of 21 Enterobacteriaceae were 76.2%, 81.0%, and 81.0%, respectively. ConclusionsTigecycline displays effective in vitro antibacterial activity to clinical common multidrug-resistant bacteria (excluding Pseudomonas aeruginosa), but different susceptibility testing methods have shown different susceptibility rates. For Acinetobacter baumannii, KB method is superior to Vitek 2 Compact system, and for Enterobacteriaceae, Vitek 2 Compact system is superior to KB method.
Objective To probe the distribution and drug resistance of pathogens causing surgical site infection in patients after gynecologic operation, and provide reference for prevention and treatment. Methods Seventy patients with incision infection after gynecologic operation in West China Second University Hospital of Sichuan University from January 2010 to May 2015 were selected. Species of the pathogens from the submitted specimens and the results of the drug susceptibility testing were analyzed. Results Seventy-two strains of pathogens were isolated, including 36 strains (50.0%) of Gram-negative (G–) bacteria and 36 strains (50.0%) of Gram-positive (G+) bacteria. The main G– bacteria were Escherichia coli (36.1%) and Enterobacter cloacae (5.6%); the main G+ bacteria were Staphylococcus aureus (18.1%), Staphylococcus epidermidis (12.5%), and Enterococcus faecalis (8.3%). Escherichia coli showed low sensitivities to ampicillin, ceftriaxone, and gentamicin, with resistance rates of 76.9%, 61.5%, and 61.5%, respectively. Staphylococcus aureus showed low sensitivities to penicillin G, clindamycin, and erythromycin, with resistance rates of 92.3%, 69.2%, and 61.5%, respectively. Staphylococcus epidermidis showed low sensitivities to erythromycin, penicillin G, and ciprofloxacin, with resistance rates of 88.9%, 77.8%, and 77.8%, respectively. No carbapenem-resistant G– bacteria or vancomycin-resistant G+ bacteria were detected. Conclusion Postoperative surgical site infection is the most common nosocomial infection. The main bacteria related to postoperative incision infection in the gynecology department of the hospital are Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis, and Enterococcus faecalis, which become resistant to common antibiotics currently. Therefore more attention should be paid to bacterial isolation and drug susceptibility test results for rational use of antimicrobial drugs and effectiveness of the treatment to nosocomial infection.
ObjectiveTo understand the drug resistance of Mycobacterium tuberculosis complex in West China Hospital, Sichuan University, analyze its drug resistance characteristics, and provide reference for the monitoring of drug-resistant tuberculosis.MethodsFrom January 2016 to March 2018, Mycobacterium tuberculosis drug susceptibility testing kit was used to detect the drug susceptibility of Mycobacterium tuberculosis culture-positive strains in Department of Laboratory Medicine, West China Hospital, Sichuan University. The tested drugs included four of the first-line anti-tuberculosis drugs: rifampicin, isoniazid, ethambutol, and streptomycin, and ten of the second-line anti-tuberculosis drugs: capreomycin, ofloxacin, ethionamide, p-aminosalicylic acid, levofloxacin, moxifloxacin, rifabutin, amikacin, kanamycin, and chlorine phenazine.ResultsA total of 130 patients (130 strains) were enrolled, including 82 newly diagnosed patients (82 strains) and 48 re-treated patients (42 strains). The drug resistance rate of the 130 patients was 37.69%. The drug resistance rate of the newly diagnosed patients (28.05%) was significantly lower than that of the re-treated patients (54.17%), and there was a statistical difference (χ2=8.794, P=0.003). The multi-drug resistance rate of the newly diagnosed patients (6.10%) was significantly lower than that of the re-treated patients (25.00%), and the difference was statistically significant (χ2=9.517, P=0.002). The resistance rate of isoniazid, rifampicin, and streptomycin in newly diagnosed patients (23.17%, 8.54%, and 7.32%, respectively) were significantly lower than those in the re-treated patients (45.83%, 41.67%, and 29.17%, respectively), and the differences were statistically significant (P<0.05). The resistance rate of ofloxacin, moxifloxacin, rifabutin and ethionamide in the newly diagnosed patients (9.76%, 8.54%, 7.31%, and 4.88%, respectively) were significantly lower than those in the re-treated patients (39.58%, 27.08%, 25.00%, and 22.92%, respectively), and the differences were statistically significant (P<0.05).ConclusionIt is necessary to strengthen the standardized treatment of patients with newly diagnosed tuberculosis, increase the treatment and management of re-treated tuberculosis patients, and prevent the generation and spread of drug-resistant patients, especially multidrug-resistant patients.
Inappropriate and irrational prescription of antimicrobial agents has led to increasing bacterial resistance, which has become a major concern around the world. Clinical microbiology service provides a basis and guarantee for the rational application of antimicrobial agents and an important technical support for antimicrobial stewardship, and plays an important role in promoting the rational use of antimicrobial agents. This paper summarizes and evaluates the specific role and technical requirements of clinical microbiology service in the diagnosis of infectious diseases, rational application of antimicrobial agents, hospital infection control and training of medical staff, so as to provide a technical guidance for clinical microbiology service in the antimicrobial stewardship.