Factors associated with tuberculin reactivity in two general hospitals in Mexico.

OBJECTIVE: To identify risk factors associated with tuberculin reactivity in healthcare workers (HCWs). DESIGN: Cross-sectional survey of tuberculin reactivity (2 TU of purified protein derivative (PPD) RT23, using the Mantoux two-step test). SETTING: Two general hospitals located in a region with a high prevalence of tuberculosis and high bacille Calmette-Guerin (BCG) coverage. PARTICIPANTS: Volunteer sample of HCWs. RESULTS: 605 HCWs were recruited: 71.2% female; mean age, 36.4 (standard deviation [SD], 8.2) years; 48.9% nurses, 10.4% physicians, 26.8% administrative personnel; mean time of employment, 10.9 (SD, 6.7) years. PPD reactivity (> or =10 mm) was found in 390 (64.5%). Multivariate analysis revealed an association of tuberculin reactivity with occupational exposure in the hospital: participation in autopsies (odds ratio [OR], 9.3; 95% confidence interval [CI95], 2.1-40.5; P=.003.), more than 1 year of employment (OR, 2.4; CI95, 1.1-5.0; P=.02), work in the emergency or radiology departments (OR, 2.0; CI95, 1.03-3.81; P=.04), being physicians or nurses (OR, 1.5; CI95, 1.04-2.11; P=.03), age (OR, 1.04; CI95, 1.02-1.07 per year of age; P<.001), and BCG scar (OR, 2.1; CI95, 1.2-3.4; P=.005). CONCLUSIONS: Although the studied population has a high baseline prevalence of tuberculosis infection and high coverage of BCG vaccination, nosocomial risk factors associated with PPD reactivity were identified as professional risks; strict early preventive measures must be implemented accordingly.     

Parenteral nutrition as a risk factor for central venous catheter-related infection

BACKGROUND: The role of parenteral nutrition (PN) therapy as an independent risk factor for central venous catheter (CVC)-related infection in nonselected adult patients is not well established. The aim of this study was to evaluate PN as a risk factor for central venous catheter-related infection in nonselected adult patients in a general university hospital. METHODS: Patients using central venous catheters, exposed or nonexposed to PN, were prospectively followed for development of central venous catheter-related infection. RESULTS: One hundred fifty-three patients were studied; 28 developed central venous catheter-related infection. Patients with central venous catheter-related infection presented higher frequency of PN use than patients without infection (60.7 vs 34.4%; p = .010). Multivariate Cox analysis showed that PN (relative risk (RR) = 3.30; 95% confidence interval [CI], 1.30-8.34; p = .012) was the only risk factor for central venous catheter-related infection. Malnutrition (RR = 0.45; 95% CI, 0.15-1.34; p = .152), days of hospitalization before central venous catheter insertion (RR = 1.00; 95% CI, 0.98-1.02; p = .801), and sustained hyperglycemia (RR = 0.49; 95% CI, 0.98-1.21; p = .091) were not significant in the model. Multiple logistic regression revealed that mal-nutrition (odds ratio [OR] = 8.05; 95% CI, 1.85-35.03; p = .005), central venous catheter indication for surgical-related pathology (OR = 7.26; 95% CI, 2.51-21.04; p < .001), sustained hyperglycemia (OR = 4.34; 95% CI, 1.79-10.52; p = .001), and days of hospitalization before central venous catheter insertion (OR = 1.04; 95% CI, 1.01-1.07; p = .004) were associated with PN use after adjustment for Assessment Score Intervention System score (OR = 0.33; 95% CI, 0.14-0.80; p = .014). CONCLUSIONS: PN therapy is an independent risk factor for central venous catheter-related infection in nonselected hospitalized adult patients.     

Retrospective analysis of catheter-related infections in a hemodialysis unit.

OBJECTIVE: To compare the incidence rates of catheter-related bloodstream infection associated with different vascular access methods in patients receiving hemodialysis. SETTING: Tertiary care public hospital in Western Australia. DESIGN: Retrospective analysis of surveillance data collected by the hospital's infection control department. METHODS: The number of confirmed bloodstream infections for each type of vascular access was identified for the period from July 2002 through June 2003. The corresponding number of patient-days was determined to calculate the infection incidence rates. The serially correlated data were then analyzed using Poisson generalized estimating equations. RESULTS: A total of 32 confirmed bloodstream infections were identified. Infection rates, in number of infections per 1,000 patient-days, were as follows: 0.4 for native arteriovenous fistulae; 2.86 for synthetic arteriovenous grafts; 4.02 for permanent, tunneled, cuffed central venous catheters; and 20.2 for temporary, nontunneled, noncuffed central venous catheters. Compared with permanent catheters, the monthly infection rate associated with the temporary catheters was significantly higher (incident rate ratio [IRR], 5.025 [95% confidence interval {CI}, 1.532-16.484]; P=.008) and that of arteriovenous fistulae was significantly lower (IRR, 0.099 [95% CI, 0.030-0.324]; P=.001). The monthly infection rate for arteriovenous grafts was not significantly different from that for permanent central venous catheters (IRR, 0.702 [95% CI, 0.246-2.008]; P=.510). CONCLUSIONS: A hierarchy of infection risk associated with vascular access type is evident. Native arteriovenous fistulae should be recommended for all patients receiving chronic hemodialysis, to minimize infection.     

Increased rate of catheter-related bloodstream infection associated with use of a needleless mechanical valve device at a long-term acute care hospital.

OBJECTIVE: To determine whether introduction of a needleless mechanical valve device (NMVD) at a long-term acute care hospital was associated with an increased frequency of catheter-related bloodstream infection (BSI). DESIGN: For patients with a central venous catheter in place, the catheter-related BSI rate during the 24-month period before introduction of the NMVD, a period in which a needleless split-septum device (NSSD) was being used (hereafter, the NSSD period), was compared with the catheter-related BSI rate during the 24-month period after introduction of the NMVD (hereafter, the NMVD period). The microbiological characteristics of catheter-related BSIs during each period were also compared. Comparisons and calculations of relative risks (RRs) with 95% confidence intervals (CIs) were performed using chi (2) analysis. RESULTS: Eighty-six catheter-related BSIs (3.86 infections per 1,000 catheter-days) occurred during the study period. The rate of catheter-related BSI during the NMVD period was significantly higher than that during the NSSD period (5.95 vs 1.79 infections per 1,000 catheter-days; RR, 3.32 [95% CI, 2.88-3.83]; P<.001). A significantly greater percentage of catheter-related BSIs during the NMVD period were caused by gram-negative organisms, compared with the percentage recorded during the NSSD period (39.5% vs 8%; P=.007). Among catheter-related BSIs due to gram-positive organisms, the percentage caused by enterococci was significantly greater during the NMVD period, compared with the NSSD period (54.8% vs 13.6%; P=.004). The catheter-related BSI rate remained high during the NMVD period despite several educational sessions regarding proper use of the NMVD. CONCLUSIONS: An increased catheter-related BSI rate was temporally associated with use of a NMVD at the study hospital, despite several educational sessions regarding proper NMVD use. The current design of the NMVD may be unsafe for use in certain patient populations.     

Risk factors for recovery of imipenem- or ceftazidime-resistant pseudomonas aeruginosa among patients admitted to a teaching hospital in Brazil.

BACKGROUND: The prevalence of resistance to imipenem and ceftazidime among Pseudomonas aeruginosa isolates is increasing worldwide. OBJECTIVE: Risk factors for nosocomial recovery (defined as the finding of culture-positive isolates after hospital admission) of imipenem-resistant P. aeruginosa (IRPA) and ceftazidime-resistant P. aeruginosa (CRPA) were determined. DESIGN: Two separate case-control studies were conducted. Control subjects were matched to case patients (ratio, 2:1) on the basis of admission to the same ward at the same time as the case patient. Variables investigated included demographic characteristics, comorbid conditions, and the classes of antimicrobials used. SETTING: The study was conducted in a 400-bed general teaching hospital in Campinas, Brazil that has 14,500 admissions per year. Case patients and control subjects were selected from persons who were admitted to the hospital during 1992-2002. RESULTS: IRPA and CRPA isolates were obtained from 108 and 55 patients, respectively. Statistically significant risk factors for acquisition of IRPA were previous admission to another hospital (odds ratio [OR], 4.21 [95% confidence interval {CI}, 1.40-12.66]; P=.01), hemodialysis (OR, 7.79 [95% CI, 1.59-38.16]; P=.01), and therapy with imipenem (OR, 18.51 [95% CI, 6.30-54.43]; P<.001), amikacin (OR, 3.22 [95% CI, 1.40-7.41]; P=.005), and/or vancomycin (OR, 2.48 [95% CI, 1.08-5.64]; P=.03). Risk factors for recovery of CRPA were previous admission to another hospital (OR, 18.69 [95% CI, 2.00-174.28]; P=.01) and amikacin use (OR, 3.69 [95% CI, 1.32-10.35]; P=.01). CONCLUSION: Our study suggests a definite role for several classes of antimicrobials as risk factors for recovery of IRPA but not for recovery of CRPA. Limiting the use of only imipenem and ceftazidime may not be a wise strategy to contain the spread of resistant P. aeruginosa strains.     

Central venous catheter-related bacteremia due to gram-negative bacilli: significance of catheter removal in preventing relapse.

OBJECTIVE: To study the characteristics of catheter-related, gram-negative bacteremia (GNB) and the role of central venous catheter (CVC) removal. DESIGN: This retrospective study involved a search of the microbiological department records of CVC and blood cultures and patients' medical records. SETTING: University of Texas M. D. Anderson Cancer Center, a tertiary-care hospital in Houston, Texas. PATIENTS: Patients with cancer who had catheter-related GNB, defined as (1) a positive catheter tip culture with at least 15 colony-forming units semiquantitatively, (2) isolation of the same organism from the tip and peripheral blood cultures, (3) no other source for bacteremia except the CVC, and (4) clinical manifestations of infection (fever or chills). RESULTS: Between January 1990 and December 1996, 72 cases of catheter-related GNB were available for review. Most of the patients (67; 93%) had their CVCs removed in response to the bacteremia. Few patients (5; 7%) retained their CVCs and were treated with appropriate antibiotics. When CVCs were removed, only 1 patient (1%) relapsed with the same organism, whereas all 5 patients with retained CVCs relapsed after having responded (P < .001). The most commonly isolated organisms were Enterobacter, Klebsiella, Stenotrophomonas, Pseudomonas, and Acinetobacter species. Catheter removal within 72 hours of the onset of the catheter-related GNB was the only independent protective factor against relapse of the infection (odds ratio, 0.13; 95% confidence interval, 0.02-0.75; P = .02). CONCLUSION: In patients with documented catheter-related GNB, CVCs should be removed within 48 to 72 hours to prevent relapse.     

NICU早产儿PICC导管相关血流感染高危因素的Meta分析

目的 通过Meta分析客观地确定NICU早产儿PICC导管相关血流感染的主要高危因素,为预防早产儿PICC导管相关血流感染提供一定的循证证据支持。方法 在线检索CNKI、万方、维普、Cochrane Library、PubMed、EMBASE等数据库,检索年限从各数据库建库起始至2019年1月,有关公开发表的早产儿PICC导管相关血流感染高危因素的文献,由两名研究员独立完成文献筛选、质量评价及资料提取,采用RevMan5.3软件进行Meta分析。结果 经筛选共纳入10篇文献（中文1篇,英文9篇）进行Meta分析。胎龄＜32周(OR=0.26, 95%CI:0.10~0.66),出生体重＜750g(OR=0.53, 95%CI:0.41~0.69),股三角部位置管(OR=1.67, 95%CI:1.31~2.11),置管耗时≥60min(OR=0.61, 95%CI:0.38~0.97),留置管时间≥30天(OR=2.41, 95%CI:1.75~3.31),留置CVC导管数量≥2个(OR=0.21, 95%CI:0.17~0.25)是高危因素。结论 胎龄愈小、出生体重越低、经股三角部位置管、置管耗时和导管留置时间越长、留置多个CVC导管是早产儿PICC置管后发生导管相关血流感染的高危因素,医护人员可采取有效预防措施,降低导管相关血流感染的发生率。     

Risk factors for surgical-site infections following cesarean section.

OBJECTIVE: To identify risk factors associated with surgical-site infections (SSIs) following cesarean sections. DESIGN: Prospective cohort study. SETTING: High-risk obstetrics and neonatal tertiary-care center in upstate New York. PATIENTS: Population-based sample of 765 patients who underwent cesarean sections at our facility during 6-month periods each year from 1996 through 1998. METHODS: Prospective surgical-site surveillance was conducted using methodology of the National Nosocomial Infections Surveillance System. Infections were identified during admission, within 30 days following the cesarean section, by readmission to the hospital or by a postdischarge survey. RESULTS: Multiple logistic-regression analysis identified four factors independently associated with an increased risk of SSI following cesarean section: absence of antibiotic prophylaxis (odds ratio [OR], 2.63; 95% confidence interval [CI95], 1.50-4.6; P=.008); surgery time (OR, 1.01; CI95, 1.00-1.02; P=.04); <7 prenatal visits (OR, 3.99; CI95, 1.74-9.15; P=.001); and hours of ruptured membranes (OR, 1.02; CI95, 1.01-1.03; P=.04). Patients given antibiotic prophylaxis had significantly lower infection rates than patients who did not receive antibiotic prophylaxis (P=02), whether or not active labor or ruptured membranes were present. CONCLUSION: Among the variables identified as risk factors for SSI, only two have the possibility to be changed through interventions. Antibiotic prophylaxis would benefit all cesarean patients regardless of active labor or ruptured membranes and would decrease morbidity and length of stay. Women's healthcare professionals also must continue to encourage pregnant women to start prenatal visits early in the pregnancy and to maintain scheduled visits throughout the pregnancy to prevent perinatal complications, including postoperative infection.     

Investigation of an outbreak of gram-negative bacteremia among hematology-oncology outpatients.

OBJECTIVE: To identify risk factors associated with an outbreak of gram-negative bacteremia (GNB). SETTING: A university hospital. PATIENTS: Hematology-oncology outpatients. DESIGN: Retrospective case-control study. RESULTS: Thirty-eight patients developed GNB; 13 patients experienced more than one episode, and eight blood cultures grew more than one gram-negative organism. The most frequently isolated organisms were Stenotrophomonas maltophilia, Klebsiella pneumoniae, Acinetobacter baumannii, and Acinetobacter johnsonii. When the GNB patients (cases) were compared with randomly selected hematology-oncology patients (controls), central venous catheter (CVC) self-care (71% vs 39%; P=.02), and duration of recent hospital stay (median, 15 vs 4 days; P=.01) were identified as risk factors. In a logistic regression model, duration of recent hospital stay was the only risk factor significantly associated with GNB (odds ratio, 1.05; 95% confidence interval, 1.01-1.08; P<.02). CONCLUSIONS: Hematology-oncology patients providing their own CVC care who have recently been hospitalized for more than 2 weeks may be at increased risk of GNB. CVCs should be protected from possible environmental contamination in hematologyoncology patients. Patients providing their own CVC care should undergo continued rigorous education regarding proper CVC care.     

基层医院导尿相关尿路感染的危险因素分析

目的分析基层医院导尿相关尿路感染的相关危险因素。方法218例接受导尿的患者中,并发尿路感染者79例,为试验组;未发生感染者139例,为对照组。记录年龄、性别、住院诊断、尿管留置时间、是否预防性使用抗生素、卧床时间、是否膀胱冲洗等因素。结果Logistic多因素统计分析显示尿管留置时间≥7天(OR值5.59;95%CI 1.94～16.16)、卧床时间≥15天(OR值4.23;95%CI 1.85～9.67)、膀胱冲洗(OR值3.63;95%CI 1.83～7.23)与导尿并发尿路感染明显相关。结论尿管留置时间≥7天、卧床时间≥15天、膀胱冲洗是导尿并发尿路感染的独立危险因素。     

Nosocomial infections in a children's hospital in Argentina: impact of a unique infection control intervention program.

OBJECTIVE: To assess the efficacy of parental education and use of parents as nursing assistants on reducing nosocomial infections. DESIGN: Prospective study. METHODS: Active surveillance for nosocomial infections was performed on two wards. On ward A, parents were educated about infection control practices and assisted nursing staff with routine tasks, so that nursing personnel could focus their efforts on procedures with higher risk of infection. Parental assistance was not sought on ward B, the comparison ward. RESULTS: From October 1990 through September 1991, 1,081 patients were admitted to wards A (470) or B (611). The over-all nosocomial infection rate was 7.1 per 100 admissions; the nosocomial infection rate was significantly higher on ward B than ward A (63/611 vs 14/470; P<.001). Multivariate analysis identified risk factors for nosocomial infection on the two wards as age <2 years (P=.01), malnutrition (P=.005), duration of hospitalization (P<.001), ward B hospitalization (P=.003), and ward cleanliness score (P=.009); the distribution of patients with these factors was similar on the two wards. CONCLUSIONS: Our data suggest that parental infection control education and recruitment to relieve nursing staff of routine low-risk procedures are economical and easily implemented measures to reduce nosocomial infections in hospitals with limited personnel resources in the developing world.     

Risk factors for colonization with vancomycin-resistant enterococci in a Melbourne hospital.

OBJECTIVE: To determine risk factors for colonization with vancomycin-resistant enterococci (VRE) in a hospital outbreak. DESIGN: Outbreak investigation and case-control study. SETTING: A referral teaching hospital in Melbourne, Australia. PARTICIPANTS: Cases were inpatients colonized (with or without clinical disease) with VRE between July 26 and November 28, 1998; controls were hospitalized patients without VRE. METHODS: Five cases of VRE were identified between July 26 and November 8, 1998, by growth of VRE from various sites. Active case finding by cultures of rectal swabs from patients surveyed in wards was commenced on July 26, after the first isolate of VRE. RESULTS: There were 19 cases and 66 controls. All the VRE identified were vanB, and all were Enterococcus faecium. One molecular type predominated (18/19 cases). In a logistic-regression model, being on the same ward as a VRE case was the highest risk factor (odds ratio [OR], 82; 95% confidence interval [CI95], 5.7-1,176; P=.001). Having more than five antibiotics (OR, 11.9; CI95 1.1-129.6; P<.05), use of metronidazole (OR, 10.9; CI95, 1.7-69.8; P=.01), and being a medical patient (OR, 8.1; CI95, 1.4-47.6; P<.05) also were significant. Intensive care unit admission was associated with decreased risk (OR, 0.1; CI95, 0.01-0.8; P<.05). CONCLUSION: Our findings are consistent with an acute hospital outbreak. Monitoring and control of antibiotic use, particularly metronidazole, may reduce VRE in our hospital. Ongoing surveillance and staff education also are necessary.     

A multicenter intervention to prevent catheter-associated bloodstream infections.

BACKGROUND: Education-based interventions can reduce the incidence of catheter-associated bloodstream infection. The generalizability of findings from single-center studies is limited. OBJECTIVE: To assess the effect of a multicenter intervention to prevent catheter-associated bloodstream infections. DESIGN: An observational study with a planned intervention. SETTING: Twelve intensive care units and 1 bone marrow transplantation unit at 6 academic medical centers. PATIENTS: Patients admitted during the study period. INTERVENTION: Updates of written policies, distribution of a 9-page self-study module with accompanying pretest and posttest, didactic lectures, and incorporation into practice of evidence-based guidelines regarding central venous catheter (CVC) insertion and care. MEASUREMENTS: Standard data collection tools and definitions were used to measure the process of care (ie, the proportion of nontunneled catheters inserted into the femoral vein and the condition of the CVC insertion site dressing for both tunneled and nontunneled catheters) and the incidence of catheter-associated bloodstream infection. RESULTS: Between the preintervention period and the postintervention period, the percentage of CVCs inserted into the femoral vein decreased from 12.9% to 9.4% (relative ratio, 0.73; 95% confidence interval [CI], 0.61-0.88); the total proportion of catheter insertion site dressings properly dated increased from 26.6% to 34.4% (relative ratio, 1.29; 95% CI, 1.17-1.42), and the overall rate of catheter-associated bloodstream infections decreased from 11.2 to 8.9 infections per 1,000 catheter-days (relative rate, 0.79; 95% CI, 0.67-0.93). The effect of the intervention varied among individual units. CONCLUSIONS: An education-based intervention that uses evidence-based practices can be successfully implemented in a diverse group of medical and surgical units and reduce catheter-associated bloodstream infection rates.     

Risk factors for surgical site infection complicating laminectomy.

OBJECTIVE: To examine risk factors for surgical site infection (SSI) following spinal surgery and to analyze the associations between a surgeon's years of operating experience and surgical specialty and patients' SSI risk. DESIGN: Case-control study. SETTING: A tertiary care facility and a community hospital in Durham, North Carolina. PATIENTS: Each case patient who developed an SSI complicating laminectomy was matched with 2 noninfected control patients by hospital, year of surgery, and National Nosocomial Infection Surveillance System risk index score. RESULTS: Forty-one case patients with SSI complicating laminectomy and 82 matched control patients were analyzed. Nonwhite race, diabetes and an elevated body mass index (BMI) were more common among case patients than among control patients. Subjects with a BMI greater than 35 were more likely to undergo a prolonged procedure, compared with case patients who had a BMI of 35 or less. The SSI rate for patients operated on by neurosurgeons was 28%, compared with 43% for patients operated on by orthopedic surgeons (odds ratio [OR], 0.5; P=.12). The number of years of operating experience were not associated with SSI risk. Multivariate analysis revealed diabetes (OR, 4.2 [95% confidence interval {CI}, 1.1-16.3]; P=.04), BMI greater than 35 (OR, 7.1 [95% CI, 1.8-28.3]; P=.005), and laminectomy at a level other than cervical (OR, 6.7 [95% CI, 1.4-33.3]; P=.02) as independent risk factors for SSI following laminectomy. CONCLUSION: Diabetes, obesity, and laminectomy at a level other than cervical are independent risk factors for SSI following laminectomy. Preoperative weight loss and tight perioperative control of blood glucose levels may reduce the risk of SSI in laminectomy patients.     

基层医院导尿相关尿路感染的危险因素分析

目的 分析基层医院导尿相关尿路感染的相关危险因素。方法218例接受导尿的患者中,并发尿路感染者79例,为试验组;未发生感染者139例,为对照组。记录年龄、性别、住院诊断、尿管留置时间、是否预防性使用抗生素、卧床时间、是否膀胱冲洗等因素。结果Logistic多因素统计分析显示尿管留置时间≥7天（OR值5．59;95％CI1．94～16．16）、卧床时间≥15天（OR值4．23;95％CI1．85～9．67）、膀胱冲洗（OR值3．63;95％CI1．83～7．23）与导尿并发尿路感染明显相关。结论尿管留置时间≥7天、卧床时间≥15天、膀胱冲洗是导尿并发尿路感染的独立危险因素。     

Injectable progestin contraceptive use and risk of HIV infection in a South African family planning cohort

OBJECTIVE: To investigate whether the incidence of HIV infection is higher among sexually active women using depot medroxyprogesterone acetate (DMPA) or noresthisterone enanthate (NET-EN) injections for contraception than among women using nonhormonal or no contraception. METHODS: Five hundred and fifty-one initially HIV-negative women were followed up for a total of 491 person-years. Participants were interviewed, counselled, examined, tested for HIV and other STIs, and treated, at three monthly intervals for 1 year. RESULTS: There was no significant association between progestin contraceptive use and HIV infection (rate ratio 1.1, 95% CI 0.5 to 2.8; log-rank test, p=.73). In proportional hazards regression, the only significant hazard ratios for HIV acquisition were prevalent Neisseria gonorrhoea (5.2; 95% CI 1.1 to 23.7, p=.035) and Trichomonas vaginalis (4.8; 95% CI 1.0 to 22.8, p=.049); bacterial vaginosis was marginally significant (2.8; 95% CI 1.0 to 8.3, p=.057). The adjusted hazard ratios for NET-EN and DMPA were 1.76 (95% CI 0.64 to 4.84) and 0.46 (95% CI 0.06 to 3.79), respectively, relative to nonuse. Five hundred and twelve of 551 women had one or more confirmed STIs during the study. CONCLUSIONS: There is no evidence of an association between HIV infection and injectable contraceptives. Due to the limited power of this study and because similar studies have not included young women using NET-EN, we recommend that further research be carried out to focus on the use of NET-EN and HIV acquisition in high risk groups.     

Risk factors for and impact of infection or colonization with aztreonam-resistant Pseudomonas aeruginosa.

OBJECTIVE: To identify risk factors for infection or colonization with aztreonam-resistant Pseudomonas aeruginosa and examine the impact of this organism on mortality. DESIGN: A case-control study was performed to identify risk factors for infection or colonization with aztreonam-resistant P. aeruginosa. A cohort study was subsequently performed to examine the impact of aztreonam resistance on outcomes. SETTING: A tertiary referral center in southeastern Pennsylvania.Participants. Inpatients with a clinical culture positive for P. aeruginosa between January 1, 1999, and December 31, 2000. RESULTS: Of 720 P. aeruginosa. isolates, 183 (25.4%) were aztreonam-resistant and 537 (74.6%) were aztreonam susceptible. In a multivariable model, prior fluoroquinolone use (adjusted odds ratio [aOR], 1.81 [95% confidence interval {CI}, 1.17-2.80]), prior use of an antianaerobic agent (aOR, 1.56 [95% CI, 1.06-2.29]), and renal insufficiency (aOR, 1.59 [95% CI, 1.10-2.29]) were associated with infection or colonization with aztreonam-resistant P. aeruginosa, while older age (aOR, 0.98 [95% CI, 0.97-0.99] per year of age) was negatively associated with infection or colonization with this organism. In-hospital mortality was higher among subjects infected or colonized with aztreonam-resistant P. aeruginosa, compared with those who were infected or colonized with aztreonam-susceptible P. aeruginosa (25.7% vs 16.8%; P=.009), but in multivariable analysis, no significant association was found between infection or colonization with aztreonam-resistant P. aeruginosa and mortality. CONCLUSIONS: Curbing the use of fluoroquinolones and antimicrobials with antianaerobic activity may be an effective strategy to limit the emergence of aztreonam-resistant P. aeruginosa.     

Impact of central venous catheter type and methods on catheter-related colonization and bacteraemia

A prospective, randomized, controlled, multi-centre clinical trial was performed to test the effectiveness of an antimicrobial central venous catheter (CVC) made of polyurethane integrated with silver, platinum and carbon black (Vantex). Adults expected to require a CVC for more than 60 h were eligible, and were randomized to receive the test or control catheter. All CVCs were inserted with new venipunctures using full aseptic technique. Following catheter removal, the distal tip and an intracutaneous segment were removed and cultured using semiquantitative and quantitative methods. Peripheral blood samples were obtained and cultured to confirm cases of catheter-related bloodstream infection (CRBSI). Bacterial and fungal organisms were identified by standard microbiological methods. Catheter placement was performed primarily in the intensive care unit (50%) or operating theatre (42%). Complete data could be evaluated for 539 patients (77%). The mean duration of CVC placement was 149.3h (six days). There were no significant differences in colonization or bacteraemia rates between the test and control catheters. The overall colonization rate was not particularly low (24.5%), and yet CVC-related bacteraemia occurred in only 1.4% of patients, and CRBSI occurred in only one patient from the control group (0.2%). Insertion site and dressing change frequency were significantly associated with the colonization rate. Although CVCs with antimicrobial features have been associated with a decrease in catheter-related colonization and bacteraemia, this study demonstrated that infection rates may depend more on non-catheter-related factors, such as adherence to infection control standards, selection of insertion site, duration of CVC placement, and dressing change frequency. As microbial resistance increases, clinicians should make maximal use of these processes to reduce catheter-related infections.     

Risk of tuberculous infection among healthcare workers in a tertiary-care hospital in Ankara, Turkey.

OBJECTIVE: To determine risk factors for tuberculin skin test (TST) positivity among healthcare workers (HCWs). DESIGN: Two-step TST was performed in 2002. SETTING: Tertiary-care hospital in Ankara, Turkey. PARTICIPANTS: A sample of 491 hospital HCWs were included. Information related to demographics, profession, work duration, department, and individual and family history of tuberculosis (TB) was obtained by a structured questionnaire. RESULTS: Four hundred eight (83%) had two-step TST positivity. On multivariate analysis, male physicians (relative risk [RR], 1.5; 95% confidence interval [CI95], 1.23-1.69; P = .001), nurses (RR, 1.5; CI95, 1.29-1.66; P = .005), radiology technicians (RR, 1.7; CI95, 1.35-1.73; P = .002), laboratory technicians (RR, 1.6; CI95, 1.3-1.74; P = .007), and male housekeepers (RR, 1.6; (HCWs). CI95, 1.38-1.7; P < .001) had a higher risk than did female physicians. Among laboratory technicians, radiology technicians had the highest TST positivity (85%). HCWs working for less than 1 year (RR, 0.8; CI95, 0.72-0.98; P = .027) had a lower risk of infection. The HCWs having bacille Calmette-Guerin vaccination (RR, 1.12; CI95, 1.08-1.45) had higher TST positivity. CONCLUSION: Male physicians, nurses, and laboratory technicians had increased risk of Mycobacterium tuberculosis infection in this setting, but community exposure likely accounted for most infections.     

Quinolone use as a risk factor for nosocomial Clostridium difficile-associated diarrhea.

OBJECTIVE: To determine modifiable risk factors for nosocomial Clostridium difficile-associated diarrhea (CDAD). DESIGN: Case-control study. SETTING: 300-bed tertiary-care hospital. PARTICIPANTS: Hospital inpatients present during the 3-month study period. METHODS: Case-patients identified with nosocomial CDAD over the study period were compared to two sets of control patients: inpatients matched by age, gender, and date of admission; and inpatients matched by duration of hospital stay. Variables including demographic data, comorbid illnesses, antibiotic exposure, and use of gastrointestinal medications were assessed for case- and control-patients. Conditional logistic regression was performed to identify risk factors for nosocomial CDAD. RESULTS: 27 case-patients were identified and were compared to the two sets of controls (1:1 match for each comparison set). For the first set of controls, use of ciprofloxacin (odds ratio [OR], 5.5; 95% confidence interval [CI 95], 1.2-24.8; P=.03) was the only variable that remained significant in the multivariable model. For the second set of controls, prior exposure to cephalosporins (OR, 6.7; CI 95, 1.3-33.7; P=.02) and to ciprofloxacin (OR, 9.5; CI 95, 1.01-88.4; P=.05) were kept in the final model. CONCLUSIONS: Along with cephalosporins, prior quinolone use predisposed hospitalized patients to nosocomial CDAD. Quinolones should be used judiciously in acute-care hospitals, particularly in those where CDAD is endemic.