华西医院重症监护病房连续两年院内感染革兰阴性杆菌的耐药性监测

目的调查分析我院重症监护病房（ICU）医院感染革兰阴性杆菌的菌群分布和耐药现状及耐药变迁，指导临床合理使用抗生素。方法采用E—test药敏试验测定我院重症监护病房连续两年分离的200株院内感染革兰阴性杆菌对12种抗生素的最低抑菌浓度（MIC）。结果ICU病房分离率最高的院内感染革兰阴性杆菌依次为大肠埃希菌（34％），不动杆菌属细菌（18％）,铜绿假单胞菌（15．5％），克雷伯菌属细菌（15．5％），肠杆菌属细菌（13％）；两年中总耐药率最低的是亚胺培南；呼吸道标本中最常见的为不动杆菌属细菌（23％），铜绿假单胞菌（18．7％），克雷伯菌属细菌（18．7％），大肠埃希菌（17％）；尿标本中主要分离菌为大肠埃希菌（81％）；血液标本中主要分离菌为大肠埃希菌（73％）。呼吸道标本中,2004年铜绿假单胞菌的分离率25％明显高于2003年1．4％；大肠埃希菌和肺炎克雷伯菌超广谱β-内酰胺酶（ESBLs）的发生率从2003年的47％和35．7％升高到2004年的50％和53％。结论亚胺培南对大肠埃希菌和肠杆菌属细菌均保持很高的敏感性，铜绿假单胞菌对头孢他啶和阿米卡星的敏感性最高，不动杆菌属细菌对头孢哌酮／舒巴坦、亚胺培南的敏感性最高,但对亚胺培南的耐药率呈上升趋势。因此，进行本医院、本地区的细菌耐药动态监测对指导临床抗感染经验用药是非常必要的。     

Prognostic importance of gram-negative intestinal colonization preceding pancreatic infection in severe acute pancreatitis

Objectives: To establish, firstly, whether gram-negative (re)-colonization of the gut leads to an increased risk of gram-negative pancreatic infections and whether this event is time-related and, secondly, whether the difference in the quantity and quality of micro-organisms colonizing the digestive tract influences morbidity and mortality. Design: Prospective analysis of the results of systematic semi-quantitative cultures of several body areas taken from patients with severe acute pancreatitis, during a controlled multicenter trial of adjuvant selective decontamination. Setting: Surgical intensive care units of 16 hospitals. Patients: A total of 2159 semi-quantitative cultures from the oropharynx, rectum and pancreatic tissues taken from 90 patients were analyzed. Interventions: Surveillance cultures from the oropharynx and rectum were taken on admission and repeated twice weekly and from the (peri)-pancreatic devitalized tissues (i. e. necrosis) at every relaparotomy and from drainage. Measurements and results: All gram-negative pancreatic infections were preceded by intestinal colonization with the same micro-organisms. The risk of developing a pancreatic infection following gram-negative intestinal colonization (15/42 patients) was significantly higher as compared to patients without gram-negative colonization (0/10 patiens) (p < 0.001) or to patients in whom E. coli was the only intestinal micro-organism cultured (0/30 patients) (p < 0.001). The occurrence of intestinal E. coli did not increase the risk of pancreatic infection. Gram-negative colonization of the rectum and oropharynx significantly correlated with the later development of pancreatic infection: relative risks 73.7 (p < 0.001) and 13.6 (p < 0.001), respectively. However, when both areas were evaluated simultaneously, the rectum was more significant (p < 0.001). The severity of intestinal intestinal colonization until the moment of pancreatic infection showed an increase in time in all 15 patients. In 11 of 15 patients (73 %) these infections occurred within 1 week following the first isolation from the digestive tract. Gram-negative intestinal colonization was associated with a 3.7 fold increased mortality risk (p = 0.004). Conclusions: Gram-negative intestinal colonization, E. coli excepted, is an early prognostic parameter in patients in whom pancreatic infection has not yet occurred and represents a significantly increased risk of pancreatic infections and mortality. Received: 17 June 1997 Accepted: 3 March 1998     

2005年武汉同济医院细菌耐药性监测

目的了解2005年华中科技大学同济医学院附属同济医院临床分离常见病原菌对常用抗菌药物耐药情况。方法采用纸片扩散法进行抗菌药物敏感性试验,以WHONET5.3软件分析数据。结果3119株临床分离病原菌中,前6位病原菌依次为大肠埃希菌、铜绿假单胞菌、凝固酶阴性葡萄球菌、克雷伯菌属、不动杆菌属和金葡菌。嗜麦芽窄食单胞菌居第10位。耐甲氧西林金葡菌、耐甲氧西林凝固酶阴性葡萄球菌检出率分别为53.7%、74.8%。未检出糖肽类耐药革兰阳性球菌。肠杆菌科细菌对碳青霉烯类、头孢哌酮-舒巴坦、哌拉西林-三唑巴坦、阿米卡星耐药率<30%;不发酵糖革兰阴性杆菌对碳青霉烯类、头孢哌酮-舒巴坦耐药率亦低于30%。产ESBLs大肠埃希菌和克雷伯菌属检出率分别为58.2%和44.4%。铜绿假单胞菌对头孢他啶、头孢吡肟及环丙沙星耐药率为26.6%～28.6%。嗜麦芽窄食单胞菌对替卡西林-克拉维酸、氟喹诺酮类、米诺环素耐药率较低。结论临床常见病原菌中革兰阴性杆菌约占2/3,碳青霉烯类对其抗菌活性最强。临床细菌对多数常用抗菌药物耐药率呈上升趋势。     

Efficacy of adjunctive nebulized colistin in critically ill patients with nosocomial carbapenem-resistant Gram-negative bacterial pneumonia: a multi-centre observational study

ObjectivesTo investigate the association between adjunctive nebulized colistin and treatment outcomes in critically ill patients with nosocomial carbapenem-resistant Gram-negative bacterial (CR-GNB) pneumonia.MethodsThis retrospective, multi-centre, cohort study included individuals admitted to the intensive care unit with nosocomial pneumonia caused by colistin-susceptible CR-GNB. Enrolled patients were divided into groups with/without nebulized colistin as adjunct to at least one effective intravenous antibiotic. Propensity score matching was performed in the original cohort (model 1) and a time-window bias-adjusted cohort (model 2). The association between adjunctive nebulized colistin and treatment outcomes was analysed.ResultsIn total, 181 and 326 patients treated with and without nebulized colistin, respectively, were enrolled for analysis. The day 14 clinical failure rate and mortality rate were 41.4% (75/181) versus 46% (150/326), and 14.9% (27/181) versus 21.8% (71/326), respectively. In the propensity score-matching analysis, patients with nebulized colistin had lower day 14 clinical failure rates (model 1: 41% (68/166) versus 54.2% (90/166), p 0.016; model 2: 35.3% (41/116) versus 56.9% (66/116), p 0.001). On multivariate analysis, nebulized colistin was an independent factor associated with fewer day 14 clinical failures (model 1: adjusted odds ratio (aOR) 0.59, 95% CI 0.37–0.92; model 2: aOR 0.37, 95% CI 0.21–0.65). Nebulized colistin was not associated independently with a lower 14-day mortality rate in the time-dependent analysis in both models 1 and 2.ConclusionsAdjunctive nebulized colistin was associated with lower day 14 clinical failure rate, but not lower 14-day mortality rate, in critically ill patients with nosocomial pneumonia caused by colistin-susceptible CR-GNB.     

Importance of eosinophilic structures and its correlation with acid fast bacilli in fine needle aspiration smears of tubercular lymphadenitis

BackgroundThe hallmark of tuberculosis in cytological smears is the presence of epithelioid cell granulomas, necrosis and AFB. In cases, where AFB not detected, diagnosis of tuberculosis can be made by ancillary tests like PCR which requires infrastructure besides being expensive. In India, where majority of population is rural-based there is an imminent need of some morphological change in cytological smears which can point towards diagnosis of tuberculosis in absence of AFB. This study was done to assess the importance of eosinophilic structures (ES) and its correlation with presence of AFB.Material & methodsThis was a retrospective study over a period of one year. Lymph node aspirates reported as granulomatous lymphadenitis, tubercular lesion or suppurative lesion were included. All smears for each case, stained with May Grunwald Giemsa (MGG), Hematoxylin and Eosin (H&E) and ZN stain were retrieved and rescreened for the presence of eosinophilic structure, necrosis, granulomas and AFB.ResultsOur study included 256 cases. Most common age group was 21–30 years with female predominance. Cervical lymph nodes were most commonly involved. In relation to ES and AFB four cytological pictures were seen i.e ES + AFB+ (44.54%) ES + AFB- (5.46%) ES- AFB+ (14.45%) ES - AFB- (35.55%). Chi square test showed a high significant statistical association between ES and AFB(p = 0.00001).ConclusionIn developing countries with very high TB prevalence like India, where new diagnostic modalities are unaffordable by rural population, presence of ES should be included as a morphological parameter in routine cytology reporting of tubercular lesions.     

Brain Tumors as Second Malignant Neoplasms in Patients with Osteosarcoma Treated with Adjuvant and Neoadjuvant Chemotherapy: Report of 2 Cases

Abstract

A malignant, primary brain tumor developed as Second Malignant Neoplasm (SMN) in 2/490 long-term-survivor osteosarcoma patients treated at our Institute over a 20-yr period. They developed the brain tumor (one astrocytoma and one glioblastoma) 3 and 5 yr after treatment, (chemotherapy and surgery), for localized osteosarcoma of the extremity.     

Tuberculosis diagnostics in Fiji: how reliable is culture?

Settings: Acid-fast bacilli (AFB) smear microscopy and Mycobacterium tuberculosis culture are the first-line diagnostic tests for tuberculosis (TB). The contamination of TB cultures significantly reduces the reliability of TB diagnosis.Objective: To investigate factors associated with TB culture contamination in Fiji, and the relative diagnostic performance of culture compared to microscopy.Design: All tests performed at the Daulakao Mycobacterium Reference Laboratory (DMRL) in Fiji from 2010 to 2012 were reviewed. Study variables included AFB smear and TB culture results, age and type of specimen, referring TB testing centre and patient age.Results: Of 5708 specimens reviewed, 70% had both AFB smear and culture results recorded; 421 specimens were contaminated; 2.7% of specimens were either degraded or had no result recorded. There was moderate agreement (κ = 0.577) between the two tests. Culture was more likely to be positive at higher AFB smear scores. Culture contamination was associated with distance from the DMRL, sample age and operator-associated factors.Conclusion: Increases in the speed of referral from TB testing centres or the addition of preservatives to sputum specimens may results in less culture contamination. The planned introduction of liquid culture techniques in combination with culture on Ogawa media is likely to increase the sensitivity of TB diagnosis in Fiji.     

Therapeutic potential of the

Innate immune mechanisms respond rapidly to bacterial infection. A key cellular component of the innate immune response is the neutrophil, whose cytoplasmic granules contain a variety of antimicrobial proteins and peptides. Among these is the bactericidal/permeability-increasing protein (BPI), a cationic 55 kDa protein whose selective anti-infective action against Gram-negative bacteria is based on its high (nM) affinity for lipopolysaccharide (LPS, or “endotoxin”). Binding of BPI to Gram-negative bacteria results in growth inhibition, serves as an opsonin that enhances phagocytosis of bacteria and inhibits bacteria-induced inflammatory responses by blocking the interaction of LPS with host pro-inflammatory pathways. Expression of BPI appears to be developmentally regulated as human newborns apparently have lower neutrophil BPI levels than adults. BPI expression has also recently been demonstrated in human epithelial cells where it appears to be inducible by endogenous anti-inflammatory lipids (lipoxins). BPI’s potent anti-endotoxic activity against a broad range of Gram-negative bacterial pathogens is manifest in biological fluids and renders it an attractive template for pharmaceutical development. Indeed, rBPI₂₁, an active recombinant protein derived from human BPI, has proven safe in Phase I human trials, shown promise in Phase II trials and has recently completed a Phase III trial for severe meningococcaemia with apparent benefit. Identification and evaluation of additional disease entities characterised by Gram-negative bacteraemia and/or endotoxaemia as possible targets for BPI therapy continues.     

Antimicrobial Resistance in Gram-Negative Hospital Isolates: Results of the Turkish HITIT-2 Surveillance Study of 2007

Abstract

Resistance rates to amikacin, ciprofloxacin, ceftazidime, cefepime, imipenem, cefoperazone/sulbactam and piperacillin/tazobactam in Escherichia coli (n= 438)Klebsiella pneumoniae (n= 444)Pseudomonas aeruginosa (n= 210) and Acinetobacterbaumanni (n=200) were determined with e-test in a multicenter surveillance study (HITIT-2) in 2007. ESBL production in Escherichia coli and K. pneumoniae was investigated following the CLSI guidelines. Overall 42.0% of E.coli and 41.4% of K. pneumoniae were ESBL producers. In E. coli, resistance to imipenem was not observed, resistance to ciprofloxacin and amikacin was 58.0% and 5.5% respectively. In K. pneumoniae resistance to imipenem, ciprofloxacin and amikacin was 3.1%, 17.8% 12.4% respectively. In P. aeruginosa the lowest rate of resistance was observed with piperacillin/tazobactam (18.1%). A. baumanni isolates were highly resistant to all the antimicrobial agents, the lowest level of resistance was observed against cefoperazone/sulbactam (52.0%) followed by imipenem (55.5%). This study showed that resistance rates to antimicrobials are high in nosocomial isolates and show variations among the centers.