Use of packaged entrees as part of a weight-loss diet in overweight men: an 8-week randomized clinical trial.

AIM: This study assessed the efficacy of a weight-loss diet by using packaged portion-controlled entrees vs. a self-selected diet based on the United States Department of Agriculture Food Guide Pyramid (FGP). METHODS: Sixty healthy overweight men (body mass index (BMI) 26-42 kg/m2; aged 24-60 years) were randomized into two groups for an 8-week intervention. Group E consumed two portion-controlled entrees daily, plus recommended servings from the FGP. Group P consumed a self-selected diet consisting of a recommended number of servings from the FGP. Diets were designed to be isocaloric (1700 kcal) and identical in macronutrient composition (55% carbohydrate, 25% protein and 20% fat). Participants were instructed to make no changes in physical activity levels. Each group was blinded to the protocol of the other group, and received separate diet instructions, but no behavioural or diet counselling. Outcomes included weight, BMI, body composition by dual energy X-ray absorptiometry, waist and hip circumference, blood pressure (BP), fasting blood lipids, glucose, insulin and C-reactive protein. RESULTS: Fifty-one men completed the study. The portion-control group E (n = 25) experienced greater decreases in weight (-7.4 +/- 3.1 vs. -5.1 +/- 4.0 kg), BMI (-2.4 +/- 1.0 vs. -1.6 +/- 1.3 kg/m2), fat mass (-3.6 +/- 1.8 vs. -2.5 +/- 1.8 kg), waist circumference (-6.6 +/- 3.3 vs. -4.3 +/- 2.9 cm) and diastolic BP (-6.0 +/- 7.2 vs. + 0.2 +/- 10.1 mmHg) than group P (n = 26) (p < 0.05). Consumption of a packaged entree diet resulted in greater losses of weight and fat mass, and reduced BP. CONCLUSIONS: Use of packaged entrees as part of a weight-loss diet is an effective means of achieving portion control and enhancing losses of weight and fat mass in overweight men.

Nosocomial outbreak of Microbacterium species bacteremia among cancer patients.

To date, only 6 sporadic Microbacterium species (formerly coryneform Centers for Disease Control and Prevention [CDC] groups A-4 and A-5) infections have been reported. The source, mode of transmission, morbidity, mortality, and potential for nosocomial transmission of Microbacterium species remain unknown. From 26 July through 14 August 1997, 8 episodes of coryneform CDC group A-5 symptomatic bacteremia occurred in 6 patients on the oncology ward at the Maine Medical Center. One patient died. All isolates were identified at CDC as Microbacterium species and had identical DNA banding patterns by pulsed-field gel electrophoresis. To assess risk factors for Microbacterium species infection, a retrospective cohort study was conducted. The presence of a central venous catheter was the strongest risk factor (6/6 vs. 22/48; relative risk, 3.2; P<.0001). This outbreak demonstrates significant Microbacterium species-associated morbidity and mortality in immunocompromised populations and confirms the potential for epidemic nosocomial transmission.

Control of vancomycin-resistant enterococcus in health care facilities in a region.

BACKGROUND: In late 1996, vancomycin-resistant enterococci were first detected in the Siouxland region of Iowa, Nebraska, and South Dakota. A task force was created, and in 1997 the assistance of the Centers for Disease Control and Prevention was sought in assessing the prevalence of vancomycin-resistant enterococci in the region's facilities and implementing recommendations for screening, infection control, and education at all 32 health care facilities in the region. METHODS: The infection-control intervention was evaluated in October 1998 and October 1999. We performed point-prevalence surveys, conducted a case-control study of gastrointestinal colonization with vancomycin-resistant enterococci, and compared infection-control practices and screening policies for vancomycin-resistant enterococci at the acute care and long-term care facilities in the Siouxland region. RESULTS: Perianal-swab samples were obtained from 1954 of 2196 eligible patients (89 percent) in 1998 and 1820 of 2049 eligible patients (89 percent) in 1999. The overall prevalence of vancomycin-resistant enterococci at 30 facilities that participated in all three years of the study decreased from 2.2 percent in 1997 to 1.4 percent in 1998 and to 0.5 percent in 1999 (P<0.001 by chi-square test for trend). The number of facilities that had had at least one patient with vancomycin-resistant enterococci declined from 15 in 1997 to 10 in 1998 to only 5 in 1999. At both acute care and long-term care facilities, the risk factors for colonization with vancomycin-resistant enterococci were prior hospitalization and treatment with antimicrobial agents. Most of the long-term care facilities screened for vancomycin-resistant enterococci (26 of 28 in 1998 [93 percent] and 23 of 25 in 1999 [92 percent]) and had infection-control policies to prevent the transmission of vancomycin-resistant enterococci (22 of 25 [88 percent] in 1999). All four acute care facilities had screening and infection-control policies for vancomycin-resistant enterococci in 1998 and 1999. CONCLUSIONS: An active infection-control intervention, which includes the obtaining of surveillance cultures and the isolation of infected patients, can reduce or eliminate the transmission of vancomycin-resistant enterococci in the health care facilities of a region.

Serratia liquefaciens bloodstream infections from contamination of epoetin alfa at a hemodialysis center.

BACKGROUND: In a one month period, 10 Serratia liquefaciens bloodstream infections and 6 pyrogenic reactions occurred in outpatients at a hemodialysis center. METHODS: We performed a cohort study of all hemodialysis sessions on days that staff members reported S. liquefaciens bloodstream infections or pyrogenic reactions. We reviewed procedures and cultured samples of water, medications, soaps, and hand lotions and swabs from the hands of personnel. RESULTS: We analyzed 208 sessions involving 48 patients. In 12 sessions, patients had S. liquefaciens bloodstream infections, and in 8, patients had pyrogenic reactions without bloodstream infection. Sessions with infections or reactions were associated with higher median doses of epoetin alfa than the 188 other sessions (6500 vs. 4000 U, P=0.03) and were more common during afternoon or evening shifts than morning shifts (P=0.03). Sessions with infections or reactions were associated with doses of epoetin alfa of more than 4000 U (multivariate odds ratio, 4.0; 95 percent confidence interval, 1.3 to 12.3). A review of procedures revealed that preservative-free, single-use vials of epoetin alfa were punctured multiple times, and residual epoetin alfa from multiple vials was pooled and administered to patients. S. liquefaciens was isolated from pooled epoetin alfa, empty vials of epoetin alfa that had been pooled, antibacterial soap, and hand lotion. All the isolates were identical by pulsed-field gel electrophoresis. After the practice of pooling epoetin alfa was discontinued and the contaminated soap and lotion were replaced, no further S. liquefaciens bloodstream infections or pyrogenic reactions occurred at this hemodialysis facility. CONCLUSIONS: Puncturing single-use vials multiple times and pooling preservative-free epoetin alfa caused this outbreak of bloodstream infections in a hemodialysis unit. To prevent similar outbreaks, medical personnel should follow the manufacturer's guidelines for the use of preservative-free medications.

Colonization of skilled-care facility residents with antimicrobial-resistant pathogens.

OBJECTIVES: To determine the frequency of and risk factors for colonization of skilled-care unit residents by several antimicrobial-resistant bacterial species, methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococcus (VRE), or extended-spectrum-beta-lactamase-producing (ESBL-producing) (ceftazidime resistant) Klebsiella pneumoniae or Escherichia coli. DESIGN: Point-prevalence survey and medical record review. SETTING: The skilled-care units in one healthcare facility. PARTICIPANTS: 120 skilled-care unit residents. MEASUREMENTS: Colonization by each of the four antimicrobial-resistant pathogens during a point-prevalence survey, using rectal, nasal, gastrostomy-tube site, wound, and axillary cultures, June 1-3, 1998; 117 (98%) had at least one swab collected and 114 (95%) had a rectal swab collected. Demographic and clinical characteristics were evaluated as risk factors for colonization. All isolates were strain typed by pulsed-field gel electrophoresis of total genomic deoxyribonucleic acid. RESULTS: Of 117 participants, 50 (43%) were culture positive for > or =1 antimicrobial-resistant pathogen: MRSA (24%), ESBL-producing K. pneumoniae (18%) or E. coli (15%), and VRE (3.5%). Of 50 residents culture positive for any of these four antimicrobial-resistant species, 13 (26%) were colonized by more than one resistant species; only three (6%) were on contact-isolation precautions at the time of the prevalence survey. Risk factors for colonization varied by pathogen: total dependence on healthcare workers (HCWs) for activities of daily living (ADLs) and antimicrobial receipt for MRSA, total dependence on HCWs for ADLs for ESBL-producing K. pneumoniae, and antimicrobial receipt for VRE. No significant risk factors were identified for colonization by ESBL-producing E. coli. Among colonized patients, there was a limited number of strain types for MRSA (24 patients, 4 strain types) and ESBL-producing K. pneumoniae (21 patients, 3 strain types), and a high proportion of unique strain types for VRE (4 patients, 4 strain types) and FSBL-producing E. coli (17 patients, 10 strain types). CONCLUSION: A large unrecognized reservoir of skilled-care-unit residents was colonized by antimicrobial-resistant pathogens, and co-colonization by more than one target species was common. To prevent transmission of antimicrobial-resistant pathogens in long-term care facilities in which residents have high rates of colonization, infection-control strategies may need to be modified. Potential modifications include enhanced infection-control strategies, such as universal gloving for all or high-risk residents, or screening of high-risk residents, such as those with total dependence on HCWs for ADLs or recent antimicrobial receipt, and initiation of contact-isolation precautions for colonized residents.

Evaluation of a reporting system for bacterial contamination of blood components in the United States.

BACKGROUND: The transfusion of blood components contaminated with bacteria may have serious clinical consequences, but few data are available on the incidence of these events. A national effort to assess the frequency of blood component bacterial contamination associated with transfusion reaction (the BaCon Study) was initiated to better estimate their occurrence. STUDY DESIGN AND METHODS: Standard reporting criteria, data collection forms, and a standardized reporting protocol were developed in collaboration with the American Red Cross, AABB, and the Department of Defense. Episodes reported to the BaCon Study were compared with those reported to the FDA's national reporting systems to estimate the extent to which all serious reactions associated with bacterial contamination were captured. RESULTS: During the first 2 years, 38 episodes meeting study criteria were reported; 21 were laboratory-confirmed. The estimated proportion of episodes reported to the BaCon Study (i.e., completeness of coverage) was lower than that reported to the FDA during the same period (0.33 vs. 0.68), but the positive predictive value was higher (0.66 vs.0.28). CONCLUSION: Despite the complexity of obtaining reports from a large number of United States hospitals and transfusion centers, the feasibility and usefulness of the BaCon Study were shown. This study was the only national study in the United States to monitor adverse clinical events associated with bacterial contamination of blood components. By building on hospital-based reporting of transfusion-related adverse events, the BaCon Study serves as a model for the study of other complications associated with blood and blood components.

Transfusion-transmitted bacterial infection in the United States, 1998 through 2000.

BACKGROUND: Bacterial contamination of blood components can result in transfusion-transmitted infection, but the risk is not established. STUDY DESIGN AND METHODS: Suspected cases of transfusion-transmitted bacteremia were reported to the CDC by participating blood collection facilities and transfusion services affiliated with the American Red Cross, AABB, or Department of Defense blood programs from 1998 through 2000. A case was defined as any transfusion reaction meeting clinical criteria in which the same organism species was cultured from a blood component and from recipient blood, with the organism pair confirmed as identical by molecular typing. RESULTS: There were 34 cases and 9 deaths. The rate of transfusion-transmitted bacteremia (in events/million units) was 9.98 for single-donor platelets, 10.64 for pooled platelets, and 0.21 for RBC units; for fatal reactions, the rates were 1.94, 2.22, and 0.13, respectively. Patients at greatest risk for death received components containing gram-negative organisms (OR, 7.5; 95% CI, 1.3-64.2; p = 0.009). CONCLUSION: Bacterial contamination of blood is an important cause of transfusion-transmitted infection; infection risk from platelet transfusion is higher compared with that from RBCs, and, overall, the risk of infection from bacterial contamination now may exceed that from viral agents. Recipients of components containing gram-negative organisms are at highest risk for transfusion-related death. The results of this study may help direct efforts to improve transfusion-related patient safety.

Transfusion-related sepsis due to Serratia liquefaciens in the United States.

BACKGROUND: Severe, often fatal, transfusion reactions due to bacterial contamination of blood components continue to occur. Serratia liquefaciens, an unusual human pathogen, is a recently recognized potential cause of transfusion-related sepsis. CASE REPORTS: Five episodes of transfusion-related sepsis and endotoxic shock due to S. liquefaciens were reported to the CDC from July 1992 through January 1999. One episode has been described. The remaining four, all fatal, are described here: three associated with RBC transfusion and one associated with transfusion of platelets. In each instance, the source of contamination could not be found. The implicated units tended to be older (mean RBC age 28 days), and visual discoloration was noted in each RBC unit, although usually in retrospect. CONCLUSION: S. liquefaciens is an increasingly recognized cause of transfusion-related sepsis and is associated with a high mortality rate. S. liquefaciens can contaminate both RBCs and platelets, but the mechanism(s) of contamination remain unknown. Increased attention to pretransfusion visual inspection may avert the transfusion of some S. liquefaciens-contaminated RBC units. However, more sensitive rapid diagnostic tests are needed to further reduce the risk of transfusion-related sepsis and endotoxic shock.

Determining the significance of coagulase-negative staphylococci isolated from blood cultures at a community hospital: a role for species and strain identification.

OBJECTIVES: To determine the degree to which species identification or strain relatedness assessment of successive blood culture isolates of coagulase-negative staphylococci (CNS) may improve the clinical diagnosis of bloodstream infection (BSI). SETTING: 400-bed community hospital. DESIGN: Prospective laboratory survey during which all CNS blood culture isolates obtained between mid-August 1996 and mid-February 1997 (study period) were saved and later identified to the species level; selected isolates were genotyped using pulsed-field gel electrophoresis at the Centers for Disease Control and Prevention (CDC). Retrospective review of medical records of 37 patients with multiple cultures positive for CNS. RESULTS: During the study period, 171 patients had blood cultures positive for CNS; 130 had single positive cultures and 41 had > or =2 positive cultures. Of these 41, 23 (62%) were from patients with signs and symptoms of BSI according to CDC surveillance definitions. Species identification and strain clonality of CNS isolates from patients with > or =2 positives revealed 3 (13%) of the 23 patients did not have a consistent CNS species, and another 3 (13%) did not have a consistent genotype in the > or =2 positive cultures, suggesting that CNS from these patients probably were contaminants. Thus, species identification and strain clonality assessment reduced by 27% the number of patients with BSI diagnosed based on the presence of symptoms and > or =2 positive blood cultures. CONCLUSIONS: Routine species identification and selected strain genotyping of CNS may reduce the misinterpretation of probable contaminants among patients with > or =2 positive blood cultures.

A prolonged outbreak of Pseudomonas aeruginosa in a neonatal intensive care unit: did staff fingernails play a role in disease transmission?

OBJECTIVES: To describe an outbreak of Pseudomonas aeruginosa bloodstream infection (BSI) and endotracheal tube (ETT) colonization in a neonatal intensive care unit (NICU), determine risk factors for infection, and make preventive recommendations. DESIGN: A 15-month cohort study followed by a case-control study with an environmental survey and molecular typing of available isolates using pulsed-field gel electrophoresis. SETTING AND PATIENTS: Neonates in the NICU of a university-affiliated children's hospital. INTERVENTIONS: Improved hand washing and restriction of use of long or artificial fingernails. RESULTS: Of 439 neonates admitted during the study period, 46 (10.5%) acquired P aeruginosa; 16 (35%) of those died. Fifteen (75%) of 20 patients for whom isolates were genotyped had genotype A, and 3 (15%) had genotype B. Of 104 healthcare workers (HCWs) from whom hand cultures were obtained, P aeruginosa was isolated from three nurses. Cultures from nurses A-1 and A-2 grew genotype A, and cultures from nurse B grew genotype B. Nurse A-1 had long natural fingernails, nurse B had long artificial fingernails, and nurse A-2 had short natural fingernails. On multivariate logistic regression analysis, exposure to nurse A-1 and exposure to nurse B were each independently associated with acquiring a BSI or ETT colonization with P aeruginosa, but other variables, including exposure to nurse A-2, were not. CONCLUSION: Epidemiological evidence demonstrated an association between acquiring P aeruginosa and exposure to two nurses. Genetic and environmental evidence supported that association and suggested, but did not prove, a possible role for long or artificial fingernails in the colonization of HCWs' hands with P aeruginosa. Requiring short natural fingernails in NICUs is a reasonable policy that might reduce the incidence of hospital-acquired infections.

Enterobacter cloacae bloodstream infections traced to contaminated human albumin.

In August 1996, a patient in Kansas developed an Enterobacter cloacae bloodstream infection (BSI) shortly after receiving Albuminar, a brand of human albumin. Albuminar contamination was suspected. A case-control study of patients with primary gram-negative bacterial BSIs showed that patients with E. cloacae BSIs were significantly more likely than patients with non-E. cloacae gram-negative BSIs to have received Albuminar within 3 days of developing their BSIs (3 of 5 vs. 0 of 9; OR, undefined; P=.03). The E. cloacae isolate from the Kansas patient was found by pulsed-field gel electrophoresis to be identical to the isolate from the patient's Albuminar vial, to isolates from 2 previously unopened Albuminar vials, and to an isolate from a Wisconsin patient who had received Albuminar. A worldwide recall of approximately 116,000 Albuminar vials took place. This multistate outbreak was detected because of clinical astuteness and prompt reporting. Combined epidemiological and laboratory approaches are valuable when investigating potentially contaminated blood components and plasma derivatives.

An outbreak of gram-negative bacteremia in hemodialysis patients traced to hemodialysis machine waste drain ports.

OBJECTIVE: To investigate an outbreak of gram-negative bacteremias at a hemodialysis center (December 1, 1996-January 31, 1997). DESIGN: Retrospective cohort study. Reviewed infection control practices and maintenance and disinfection procedures for the water system and dialysis machines. Performed cultures of the water and dialysis machines, including the waste-handling option (WHO), a drain port designed to dispose of saline used to flush the dialyzer before patient use. Compared isolates by pulsed-field gel electrophoresis. SETTING: A hemodialysis center in Maryland. RESULTS: 94 patients received dialysis on 27 machines; 10 (11%) of the patients had gram-negative bacteremias. Pathogens causing these infections were Enterobacter cloacae (n = 6), Pseudomonas aeruginosa (n = 4), and Escherichia coli (n = 2); two patients had polymicrobial bacteremia. Factors associated with development of gram-negative bacteremias were receiving dialysis via a central venous catheter (CVC) rather than via an arterio-venous shunt (all 10 infected patients had CVCs compared to 31 of 84 uninfected patients, relative risk [RR] undefined; P<.001) or dialysis on any of three particular dialysis machines (7 of 10 infected patients were exposed to the three machines compared to 20 of 84 uninfected patients, RR = 5.8; P = .005). E cloacae, P aeruginosa, or both organisms were grown from cultures obtained from several dialysis machines. WHO valves, which prevent backflow from the drain to dialysis bloodlines, were faulty in 8 (31%) of 26 machines, including 2 of 3 machines epidemiologically linked to case-patients. Pulsed-field gel electrophoresis patterns of available dialysis machine and patient E cloacae isolates were identical. CONCLUSIONS: Our study suggests that WHO ports with incompetent valves and resultant backflow were a source of cross-contamination of dialysis bloodlines and patients' CVCs. Replacement of faulty WHO valves and enhanced disinfection of dialysis machines terminated the outbreak.

A multistate nosocomial outbreak of Ralstonia pickettii colonization associated with an intrinsically contaminated respiratory care solution.

From 1 February through 30 April 1998, 4 hospitals reported a total of 34 patients colonized with Ralstonia pickettii. All but 1 had been exposed to 0.9% saline solution manufactured by 1 company (Modudose; Kendall, Mainsfield, MA), which was used during endotracheal suctioning. Culture of saline solution from previously unopened vials yielded R. pickettii. All available product and patient isolates were genotypically related by pulsed-field gel electrophoresis (PFGE) analysis. The contaminated saline solution was manufactured at the same plant that had been associated with a similar outbreak in 1983. The 1983 and 1998 R. pickettii isolates were unrelated, as determined by PFGE. In both 1983 and 1998, a 0. 2-microm cartridge filter was used for terminal sterilization. The detection of R. pickettii should alert hospital personnel to the possibility of product contamination. In this outbreak, prompt notification of public health agencies resulted in rapid notification of other health care providers, which likely prevented additional outbreaks.

Regional dissemination of vancomycin-resistant enterococci resulting from interfacility transfer of colonized patients.

During early 1997, the Siouxland District Health Department (SDHD; Sioux City, IA) reported an increased incidence of vancomycin-resistant enterococcal (VRE) isolates at area health care facilities. To determine the prevalence and risk factors for colonization with VRE strains at 32 health care facilities in the SDHD region, a prevalence survey and case-control study were performed. Of 2266 patients and residents, 1934 (85%) participated, and 40 (2.1%) were positive for (gastrointestinal) VRE colonization. The prevalence of VRE isolates was significantly higher in acute care facilities (ACFs) than in long-term care facilities (LTCFs) (10/152 [6.6%] vs. 30/1782 [1.7%]; odds ratio [OR], 4.1; 95% confidence interval [CI], 1.8-9.0). LTCF case patients were significantly more likely than controls to have been inpatients at any ACF (19/30 vs. 12/66; OR, 8.0; 95% CI, 2.7-23.8). Of 40 VRE isolates, 34 (85%) were a related strain. The predominant strain was present in all 12 LTCFs that had at least 1 case patient in each facility. Soon after the introduction of VRE isolates into this region, dissemination to multiple LTCFs resulted from resident transfer from ACFs to LTCFs.

Molecular subtyping of Clostridium perfringens by pulsed-field gel electrophoresis to facilitate food-borne-disease outbreak investigations.

Clostridium perfringens is a common cause of food-borne illness. The illness is characterized by profuse diarrhea and acute abdominal pain. Since the illness is usually self-limiting, many cases are undiagnosed and/or not reported. Investigations are often pursued after an outbreak involving large numbers of people in institutions, at restaurants, or at catered meals. Serotyping has been used in the past to assist epidemiologic investigations of C. perfringens outbreaks. However, serotyping reagents are not widely available, and many isolates are often untypeable with existing reagents. We developed a pulsed-field gel electrophoresis (PFGE) method for molecular subtyping of C. perfringens isolates to aid in epidemiologic investigations of food-borne outbreaks. Six restriction endonucleases (SmaI, ApaI, FspI, MluI, KspI, and XbaI) were evaluated with a select panel of C. perfringens strains. SmaI was chosen for further studies because it produced 11 to 13 well-distributed bands of 40 to approximately 1,100 kb which provided good discrimination between isolates. Seventeen distinct patterns were obtained with 62 isolates from seven outbreak investigations or control strains. In general, multiple isolates from a single individual had indistinguishable PFGE patterns. Epidemiologically unrelated isolates (outbreak or control strains) had unique patterns; isolates from different individuals within an outbreak had similar, if not identical, patterns. PFGE identifies clonal relationships of isolates which will assist epidemiologic investigations of food-borne-disease outbreaks caused by C. perfringens.

Propionibacterium as a cause of postneurosurgical infection in patients with dural allografts: report of three cases.

OBJECTIVE AND IMPORTANCE: Although Propionibacterium acnes is a common inhabitant of human skin, it is an uncommon pathogen in postoperative infections. We report three cases of postoperative wound infection/osteomyelitis caused by P. acnes. CLINICAL PRESENTATION: Three patients underwent craniotomy for a supratentorial meningioma and had a dural allograft at the time of closure. The patients presented several weeks after surgery with clinical evidence of a wound infection. INTERVENTION: All patients were diagnosed with P. acnes infection and treated for this pathogen with appropriate antibiotics. The bone flap was removed in two patients. After antibiotic therapy, all patients demonstrated no further evidence of infection. CONCLUSION: To our knowledge, this is the first published report of P. acnes infection in patients with a dural substitute. The source of infection cannot be confidently ascertained; however, two patients had strains of P. acnes from one brand of graft, which were indistinguishable by pulsed field gel electrophoresis typing.

Burkholderia cepacia respiratory tract acquisition: epidemiology and molecular characterization of a large nosocomial outbreak.

In 1994 we investigated a large outbreak of Burkholderia (formerly Pseudomonas) cepacia respiratory tract acquisition. A case patient was defined as any patient with at least one sputum culture from which B. cepacia was isolated from 1 January to 31 December 1994. Seventy cases were identified. Most (40 [61%]) occurred between 1 February and 31 March 1994; of these, 35 (86%) were mechanically ventilated patients, 30 of whom were in an intensive-care unit (ICU) when B. cepacia was first isolated. Compared with control patients who were mechanically ventilated in an ICU, these 30 case-patients were significantly more likely to have been ventilated for 2 or more days (30/30 v. 15/30; P < 0.001) or to have been intubated more than once (12/30 v. 2/30; OR = 9.3, 95% CI 1.6-68.8; P = 0.002) before the first isolation of B. cepacia. By multivariate analysis, the 35 mechanically ventilated case-patients were significantly more likely to have received a nebulized medication (OR = 11.9, 95% CI = 1.6-553.1; P < 0.001) and a cephalosporin antimicrobial (OR = 11.9, 95% CI = 1.6-553.1) in the 10 days before the first isolation of B. cepacia, compared with B. cepacia-negative control-patients matched by date and duration of most recent mechanical ventilation. Although B. cepacia was not cultured from medications or the hospital environment, all outbreak strains tested had an identical DNA restriction endonuclease digestion pattern by pulsed-field gel electrophoresis. Review of respiratory therapy procedures revealed opportunities for contamination of nebulizer reservoirs. This investigation suggests that careful adherence to standard procedures for administration of nebulized medications is essential to prevent nosocomial respiratory infections.

Ochrobactrum anthropi meningitis in pediatric pericardial allograft transplant recipients.

An epidemiologic investigation was done after 3 patients contracted Ochrobactrum anthropi meningitis at one hospital in October 1994. Neurosurgical patients with pericardial tissue implants were at greater risk of infection than other neurosurgical patients (3/14 vs. 0/566; P<.001). Cultures of implants removed from 2 case-patients, an implant at implantation, a nonimplanted pericardial tissue, and an unwrapped but unopened bottle of Hank's balanced salt solution (HBSS) grew O. anthropi. Patient and tissue isolates had identical genotypes; the isolate from the HBSS bottle had a unique genotype. Culture samples from an unopened HBSS bottle and from pericardial tissue grew Pseudomonas stutzeri of the same genotype; however, no P. stutzeri infections were detected. The investigation documented intrinsic P. stutzeri contamination of HBSS. O. anthropi contamination of tissues occurred during processing, possibly due to extrinsic contamination of HBSS. Active surveillance is needed to detect infection in patients receiving transplanted tissues, and rigorous infection control practice are necessary during tissue harvesting and processing to ensure sterility.

Possible nosocomial transmission of Pseudomonas cepacia in patients with cystic fibrosis.

OBJECTIVE: To determine whether nosocomial transmission of Pseudomonas cepacia occurred at a hospital with endemic P cepacia infection of patients with cystic fibrosis. DESIGN: Two retrospective case-control studies. SETTING: A large pediatric cystic fibrosis center. PARTICIPANTS: To assess risk factors for acquisition of P cepacia, 18 cases, defined as any patient with cystic fibrosis with first documented isolation of P cepacia in 1988 or 1989, were compared with 18 matched P cepacia-negative controls with cystic fibrosis. To assess potential modes of nosocomial P cepacia transmission, 14 cases with a hospitalization(s) between their last P cepacia-negative culture and first P cepacia-positive culture were compared with 14 hospitalized P cepacia-negative controls with cystic fibrosis. METHODS: Handwiping cultures (N = 68) and selective environmental cultures were performed. MAIN RESULTS: Cases tended to be more likely than controls to have been hospitalized at the cystic fibrosis center in the 3 months before their first P cepacia-positive culture (P = .08). In addition, cases tended to be more likely than hospitalized controls with cystic fibrosis to have had a P cepacia-positive roommate (P = .06) before becoming colonized with P cepacia organisms. Pseudomonas cepacia was cultured from the hands of two individuals: a P cepacia-colonized patient who had just undergone chest physiotherapy and consequent coughing and the investigator who shook the P cepacia-positive patient's hand after the patient's procedure. CONCLUSIONS: These results suggest that in this cystic fibrosis center, hospitalization is a risk factor for P cepacia acquisition and that person-to-person transmission of P cepacia may occur in the hospital via hand contact.

Acquisition of Pseudomonas cepacia at summer camps for patients with cystic fibrosis. Summer Camp Study Group.

To assess the risk of acquisition of Pseudomonas cepacia by person-to-person transmission at cystic fibrosis summer camps, we conducted in 1990 a study at three camps attended by patients with cystic fibrosis who had P. cepacia infection and patients without P. cepacia infection but who were considered susceptible to infection. We obtained sputum or throat cultures from campers on their arrival at, weekly during, at the end of, and 14 to 30 days after camp. We compared the incidence of sputum conversion of patients at camp with that of patients outside camp by culturing specimens from noncamper control subjects with cystic fibrosis who were known not to be infected < or = 2 weeks before and 4 to 6 weeks after camp. We also determined the risk factors for P. cepacia acquisition by determining the relative risk of acquisition between campers who were exposed versus campers who were not exposed to campers known to be infected or to potential environmental sources of P. cepacia at camp. The ribotype of P. cepacia isolates from campers with sputum conversion was compared with that of isolates from other campers and from an environmental source. The cumulative incidence of sputum conversion during the study period was 6.1% (11/181) among campers compared with no incidence (0/92) among noncampers (p = 0.02, Fisher Exact Test). The incidence of sputum conversion at camp varied according to the prevalence of campers with known infection (p < 0.001, chi-square test for trend). The rate of sputum conversion was higher in the camp with longer duration (relative risk = 12.0; 95% confidence interval = 2.7 to 53.5). Ribotyping showed that P. cepacia isolates from all 11 campers with sputum conversion were identical or similar (1 to 2 band difference) to isolates of other P. cepacia-infected campers including co-converters. These results suggest that P. cepacia can be acquired by patients with cystic fibrosis who are attending summer camp for such patients, possibly through person-to-person transmission, and that the risk increases with the prevalence of P. cepacia-infected campers and the duration of camp.