An outbreak of Serratia marcescens in two neonatal intensive care units

Outbreaks of infection in neonatal intensive care units (NICUs) due to Serratia marcescens are well recognized. In some outbreaks no point source has been found, whereas in others cross-infection has been associated with contaminated ventilator equipment, disinfectants, hands and breast pumps. We report an outbreak due to S. marcescens that involved two geographically distinct NICUs. The outbreak occurred over a six week period; 17 babies were colonized, 12 at Glasgow Royal Maternity Hospital (GRMH) and five at the Queen Mothers Hospital (QMH). At GRMH three babies developed septicaemia, of whom two died. The outbreak isolates were of the same serotype and phage type and were indistinguishable on the basis of restriction fragment length polymorphism analysis. During the outbreak, two babies shown consistently to be negative on screening, were transferred between the two units. In addition, two members of medical staff attended both units. In QMH no means of cross infection was identified. However, in GRMH the outbreak strain of S. marcescens was isolated from a laryngoscope blade and a sample of expressed breast milk.     

Temporal changes in bacterial resistance in German intensive care units, 2001-2003: data from the SARI (surveillance of antimicrobial use and antimicrobial resistance in intensive care units) project

Conservative testing revealed a stable antibiotic resistance situation for Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae and Enterobacter cloacae in 32 German intensive care units (ICUs) actively participating in the SARI (surveillance of antimicrobial use and antimicrobial resistance in ICUs) project over a three-year period (2001--2003). No significant changes were shown for methicillin-resistant S. aureus (MRSA) (P=0.501; the MRSA rate increased in 18 ICUs and decreased in 14 ICUs). The only exception was an increase in ciprofloxacin-resistant E. coli.     

Bronchoscopy in intensive care units

The authors report their 1535 urgent bronchoscopic examinations performed between 1998-2002. The examinations/interventions were requested mostly by surgical and internal medicine intensive care units. The main indications were: postoperative excretion removal, stump control, suspicion of fistula, foreign body, injury of a large bronchus, tracheal stenosis, specimen taking and bronchoscopic local drug treatment. The authors mention the most important contraindications for urgent bronchofiberscopy too: missing written consent of the patient (except the cases of unconsciousness), size discrepancy between the tool and tracheal lumen, and asthmatic attack. The authors also underline the emerging importance of both diagnostic and therapeutic bronchoscopy performed on emergency wards and intensive care units. They conclude: it's necessary for the anesthetists to get a basic level ability to work with bronchofiberscope and for pulmonologist-bronchologists to be experienced to answer the questions of other specialists.     

Evaluation of antibiotic use in intensive care units of a tertiary care hospital in Turkey

The object of this study was to evaluate the appropriateness of antibiotic use in relation to diagnosis and bacteriological findings in the intensive care units (ICUs) of a 1100-bed referral and tertiary care hospital with an antibiotic restriction policy in Turkey. Between June and December 2002, patients who received antibiotics in the medical and surgical ICUs were evaluated prospectively. Two infectious diseases (ID) specialists assessed the antibiotics ordered daily. Of the 368 patients admitted to the ICUs, 223 (60.6%) received 440 antibiotics. The most frequently prescribed antibiotics were first-generation cephalosporins (16.1%), third-generation cephalosporins (15.2%), aminoglycosides (12.1%), carbapenems (10.7%) and ampicillin-sulbactam (8.7%). Antibiotic use was inappropriate in 47.3% of antibiotics. ID specialists recommended the use of 47% of all antibiotics. An antibiotic order without an ID consultation was more likely to be inappropriate [odds ratio (OR)=13.2, P<0.001, confidence intervals (CI)=4.4-39.5]. Antibiotics ordered empirically were found to be less appropriate than those ordered with evidence of culture and susceptibility results (OR=3.8, P=0.038, CI=1.1-13.1). Inappropriate antibiotic use was significantly higher in patients who had surgical interventions (OR=3.6, P=0.025, CI=1.2-10.8). Irrational antibiotic use was high for unrestricted antibiotics. In particular, antibiotic use was inappropriate in surgical ICUs. Additional interventions such as postgraduate training programmes and elaboration of local guidelines could be beneficial.     

Epidemiologic investigation of Burkholderia cepacia acquisition in two pediatric intensive care units.

OBJECTIVES: To investigate and describe an outbreak of Burkholderia cepacia in a neonatal intensive care unit (NICU) and a pediatric intensive care unit (PICU), and to report the interventions leading to the cessation of the outbreak. DESIGN: We conducted an epidemiologic investigation of an outbreak of B. cepacia colonization or infection in two clinical wards during a 35-month period (December 1998 to October 2001). SETTING: A 500-bed, university hospital-affiliated, tertiary-care pediatric institution in Paris, France, with a 22-bed PICU and 31-bed NICU. METHODS: Ribotyping was used to determine the genotypes of B. cepacia isolates. Procedures for the maintenance and disinfection of respiratory therapy devices were reviewed. RESULTS: Thirty-two children were colonized (n = 14) or infected (n = 18) by B. cepacia in 2 wards (28 in the PICU and 4 in the NICU). In the PICU, a single ribotype was found among the isolates obtained from all of the patients except 1, and from the 6 isolates obtained from respiratory therapy devices (ie, heated humidifier water). In the NICU, the isolates obtained from the patients harbored a single ribotype unrelated to that of the epidemic strain isolated in the PICU; no environmental source of infection was found. CONCLUSION: Two different outbreaks appeared to be associated with 2 ribotypes, 1 of which was linked to patient-to-patient transmission via respiratory therapy devices. Complete elimination of the outbreak was achieved only when disposable, sterilizable, or easy-to-disinfect materials were used in the PICU. The source of infection in the NICU was not found.     

Molecular epidemiology of Serratia marcescens outbreaks in two neonatal intensive care units.

OBJECTIVE: Serratia marcescens can cause serious infections in patients in neonatal intensive care units (NICUs), including sepsis, pneumonia, urinary tract infection, and conjunctivitis. We report the utility of genetic fingerprinting to identify, investigate, and control two distinct outbreaks of S. marcescens. DESIGN: An epidemiologic investigation was performed to control two clusters of S. marcescens infections and to determine possible routes of transmission. Molecular typing by pulsed-field gel electrophoresis determined the relatedness of S. marcescens strains recovered from neonates, the environment, and the hands of healthcare workers (HCWs). SETTING: Two geographically distinct level III-IV NICUs (NICU A and NICU B) in two university-affiliated teaching hospitals in New York City. RESULTS: In NICU A, one major clone, "F," was detected among isolates recovered from four neonates and the hands of one HCW. A second predominant clone, "A," was recovered from four sink drains and one rectal surveillance culture from an asymptomatic neonate. In NICU B, four neonates were infected with clone "D," and three sink drains harbored clone "H." The attributable mortality rate from bloodstream infections was 60% (3 of 5 infants). The antimicrobial susceptibilities of clone F strains varied for amikacin, cefepime, and piperacillin/tazobactam. CONCLUSIONS: S. marcescens causes significant morbidity and mortality in preterm neonates. Cross-transmission via transient hand carriage of a HCW appeared to be the probable route of transmission in NICU A. Sinks did not harbor the outbreak strains. Antimicrobial susceptibility patterns did not prove to be an accurate predictor of strain relatedness for S. marcescens.     

ICU与非ICU感染患者病原菌分布及耐药性对比分析

目的分析重症监护室（ICU）与非ICU患者感染病原菌的分布和耐药情况，为临床抗感染治疗提供依据。方法对2006年5月-2007年5月临床各科室送检标本进行细菌分离培养与鉴定，并对ICU与非ICU患者感染病原菌分布及耐药性进行对比分析。结果从ICU患者标本中分离培养出病原菌150株，其中非发酵菌总构成比为40.67％（61/150）；非ICU患者标本分离培养出病原菌495株，非发酵菌总构成比为17.98％（89/495）。ICU患者非发酵菌检出率高于非ICU患者（χ2 ＝33.20，P＜0.01）。ICU患者分离的主要病原菌依次为真菌（21.33％）、铜绿假单胞菌（17.33％）、大肠埃希菌（12.67％）；非ICU患者分离的主要病原菌依次为真菌（20.61％）、大肠埃希菌（17.98％）、金黄色葡萄球菌（10.30％）。ICU患者感染的鲍曼不动杆菌和金黄色葡萄球菌耐药较严重；第三代头孢菌素在治疗革兰阴性杆菌感染时，ICU与非ICU患者耐药差异较大。结论ICU患者非发酵菌检出率高，其感染的病原菌耐药严重，应加强管理与监测。     

Infection control in neonatal intensive care units

Healthcare-associated infection is a major problem in acute hospital settings. Hand decontamination is considered to be the most effective means of preventing healthcare-associated infection, but is poorly performed. Few studies have examined technique, which may be important in neonatal intensive care units (NICUs) where clinical procedures are intricate and could result in contamination of many areas of the hand, resulting in cross-infection. This study examined technique in six NICUs. Eighty-eight nurses were observed. A scoring system was developed so that technique could be quantified and subjected to statistical testing. The mean score was 6.29 out of 11 when hands were washed and 3.87 out of 7 when alcohol hand rub was used, indicating that performance was not optimal. Scores for technique were not significantly different in each NICU. Senior nurses achieved higher scores for handwashing (P<0.01), as did nurses holding positive feelings about the atmosphere in their NICU (P=0.04). Junior nurses scored less well on a knowledge questionnaire than senior nurses (P<0.01). Nurses who had been employed in the neonatal unit for less than one year also scored less well (P<0.01). Differences in technique were noted when comparing the beginning and end of long shifts. These differences were not noted at the beginning and end of standard shifts.     

Stenotrophomonas maltophilia and antibiotic use in German intensive care units: data from Project SARI (Surveillance of Antimicrobial Use and Antimicrobial Resistance in German Intensive Care Units)

Risk factors for the selection of Stenotrophomonas maltophilia were analysed by correlating antimicrobial use and structure parameters (e.g. hospital type) with the incidence density of S. maltophilia and the percentage of S. maltophilia isolated from 39 intensive care units (ICUs). SARI (Surveillance of Antimicrobial Use and Antimicrobial Resistance in German Intensive Care Units) is a prospective unit- and laboratory-based surveillance system that collects data on the 13 most important organisms responsible for nosocomial infections. The percentage of S. maltophilia among these organisms and the number of S. maltophilia per 1000 patient-days were calculated. The data were subsequently correlated with antibiotic use density calculated in defined daily doses (DDDs) per 1000 patient-days and structure parameters. The data covered a total of 28 266 isolates and 431 351 DDDs. The antibiotic use density ranged from 427 to 2218, with the median being 1346. Over the two-year period, the median of S. maltophilia per 1000 patient-days was 1.4 (range 0-7.6). Calculation of antibiotic use and S. maltophilia per 1000 patient-days showed a significant positive correlation with the use of carbapenems, ceftazidime, glycopeptides and fluoroquinolones, as well as with total antibiotic use. In the multiple logistic regression analysis, carbapenem use and >12 ICU beds were independently and positively associated with a high number of S. maltophilia per 1000 patient-days. Benchmarking data provided for incidence densities of S. maltophilia in ICUs revealed the heterogeneous situation of the burden of S. maltophilia in individual ICUs. The multi-centre data showed that carbapenem use and >12 ICU beds were independent risk factors for the isolation of S. maltophilia.