RESUMO
The majority of paediatric Clostridioides difficile infections (CDI) are community-associated (CA), but few data exist regarding associated risk factors. We conducted a case-control study to evaluate CA-CDI risk factors in young children. Participants were enrolled from eight US sites during October 2014-February 2016. Case-patients were defined as children aged 1-5 years with a positive C. difficile specimen collected as an outpatient or ⩽3 days of hospital admission, who had no healthcare facility admission in the prior 12 weeks and no history of CDI. Each case-patient was matched to one control. Caregivers were interviewed regarding relevant exposures. Multivariable conditional logistic regression was performed. Of 68 pairs, 44.1% were female. More case-patients than controls had a comorbidity (33.3% vs. 12.1%; P = 0.01); recent higher-risk outpatient exposures (34.9% vs. 17.7%; P = 0.03); recent antibiotic use (54.4% vs. 19.4%; P < 0.0001); or recent exposure to a household member with diarrhoea (41.3% vs. 21.5%; P = 0.04). In multivariable analysis, antibiotic exposure in the preceding 12 weeks was significantly associated with CA-CDI (adjusted matched odds ratio, 6.25; 95% CI 2.18-17.96). Improved antibiotic prescribing might reduce CA-CDI in this population. Further evaluation of the potential role of outpatient healthcare and household exposures in C. difficile transmission is needed.
Assuntos
Creches/estatística & dados numéricos , Clostridioides difficile/fisiologia , Infecções por Clostridium/epidemiologia , Microbiologia de Alimentos/estatística & dados numéricos , Pacientes Ambulatoriais/estatística & dados numéricos , Estudos de Casos e Controles , Pré-Escolar , Infecções por Clostridium/microbiologia , Infecções Comunitárias Adquiridas/epidemiologia , Infecções Comunitárias Adquiridas/microbiologia , Feminino , Humanos , Incidência , Lactente , Masculino , Fatores de Risco , Estados Unidos/epidemiologiaRESUMO
The present study was carried out to determine how active surveillance for methicillin-resistant Staphylococcus aureus (MRSA) could be improved by the use of enrichment broth and the inclusion of extra-nasal sites with nares cultures. Molecular typing was also performed to identify colonization by single or multiple strains. Surveillance cultures for MRSA were obtained from 650 patients on admission to a medical and surgical intensive care unit (ICU) in Taiwan. MRSA was detected on directly plated vs. broth-enrichment cultures in any site at 10.0% vs. 24.2%, nares 8.2% vs. 17.5%, throat 4.8% vs. 13.4%, axilla 1.2% vs. 9.1%, and perineum 1.8% vs. 9.5%, respectively. Nares cultures alone detected only 81.5% and 72.5% of all colonized patients by direct and broth-enriched cultures, respectively. The molecular typing of 68 isolates from 17 patients revealed that multisite isolates were largely indistinguishable within each patient, but four patients had multiple subtypes and another three patients had different clonotypes. The detection of MRSA carriers was considerably enhanced by broth-enrichment cultures at multiple anatomic sites and simultaneous colonization by multiple strains at different sites can occur. Epidemiological studies are needed to determine the likelihood of subsequent nosocomial infection among colonized patients detected via direct nasal versus broth-enriched cultures from multiple sites.
Assuntos
Portador Sadio/epidemiologia , Portador Sadio/microbiologia , Meios de Cultura , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Cavidade Nasal/microbiologia , Axila/microbiologia , Técnicas Bacteriológicas , Hospitais Urbanos , Humanos , Unidades de Terapia Intensiva , Staphylococcus aureus Resistente à Meticilina/classificação , Períneo/microbiologia , Faringe/microbiologia , Vigilância da População/métodos , Escarro/microbiologia , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Taiwan/epidemiologiaRESUMO
BACKGROUND: Severe acute respiratory syndrome (SARS) was introduced to Toronto on 23 February, 2003. The outbreak was believed to be over in early May after two incubation periods had passed with no newly identified cases. However, on 20 May, 2003 a cluster of respiratory illnesses occurred in a rehabilitation facility in Toronto. These cases were later identified as SARS but not until a community hospital in which one of these cases was previously hospitalized (Hospital X) had already experienced nosocomial transmission. This report describes the outbreak investigation of nosocomial transmission of SARS at Hospital X. METHODS: An investigation of 90 probable and suspect cases of SARS associated with a hospital outbreak was performed. The investigation included death record reviews, chart reviews, case finding and contact tracing. Nursing cohorts who worked on the specific ward in which nosocomial transmission occurred had work-shift and patient-assignment records reviewed to determine source of infection. RESULTS: The greatest number of cases occurred within hospital employees (42.5%) with an average age of 51 years and 69% being female. The mean incubation period for one time exposure patients was 6.3 days (range 4 to 10 days). Twelve (13.8%) of the cases died. Five of seven nurses who cared for a specific SARS patient during this period acquired SARS. Twelve of 17 (70.6%) nursing staff who developed SARS worked with another nursing staff who was symptomatic for SARS. Staff members who worked the evening shift or the morning shift and therefore likely attended a nursing appreciation breakfast were five times more likely to acquire SARS than those who did not attend. INTERPRETATION: What was believed to be the end of the Toronto SARS outbreak led the Provincial Operations Centre (POC) to issue a directive allowing a more relaxed use of infection-control precautions during the beginning of Phase 2 of the outbreak. These relaxations of precautions were temporally associated with the nosocomial transmission of SARS to hospital staff, other patients and visitors at Hospital X. As a result of this outbreak significant changes have been made with respect to infection-control practices within Canada.
Assuntos
Síndrome Respiratória Aguda Grave/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Infecção Hospitalar/epidemiologia , Surtos de Doenças/prevenção & controle , Feminino , Hospitais Comunitários , Humanos , Transmissão de Doença Infecciosa do Paciente para o Profissional , Masculino , Pessoa de Meia-Idade , Recursos Humanos de Enfermagem Hospitalar , Ontário/epidemiologia , Síndrome Respiratória Aguda Grave/prevenção & controleRESUMO
BACKGROUND: Acinetobacter spp. are multidrug-resistant bacteria that grow well in water and cause infections with unexplained, increased summer prevalence. In August, 1996, eight infants acquired Acinetobacter spp. bloodstream infection (A-BSI) while in a nursery in the Bahamas; three infants died and an investigation was initiated. METHODS: A case patient was defined as any newborn in the nursery during August 6 to 13, 1996, with A-BSI. To identify risk factors for A-BSI we conducted a retrospective cohort study and performed environmental cultures and air sampling using settle plates. The genetic relatedness of environmental isolates was assessed by pulsed field gel electrophoresis. RESULTS: Of 33 patients in the nursery 8 (24%) met the case definition. Patients with peripheral iv catheters were more likely to develop A-BSI (8 of 21 vs. O of 10, P < 0.05). Multivariate analysis among patients with iv catheters indicated that only exposure to one nurse was an independent risk factor for developing A-BSI (P < 0.005). Nursery settle plates were more likely to grow Acinetobacter spp. than were settle plates from other hospital areas (8 of 9 vs. 0 of 5, P < 0.005); cultures from nursery air conditioners also grew Acinetobacter spp. Environmental isolates were genetically diverse. After installation of a new air conditioner in May, 1995, A-BSIs occurred more frequently during months of increased absolute humidity or environmental dew point. CONCLUSIONS: Acinetobacter spp. may cause nosocomial BSI and death among infants during periods of polyclonal airborne dissemination; breaks in aseptic technique during i.v. medication administration may facilitate transmission from the environment to the patient. Environmental conditions that increase air conditioner condensate may predispose to airborne dissemination via contaminated aerosols and increase the risk of nosocomial A-BSI.
Assuntos
Infecções por Acinetobacter/epidemiologia , Acinetobacter/isolamento & purificação , Aerossóis , Ar Condicionado , Infecção Hospitalar/epidemiologia , Berçários Hospitalares , Sepse/epidemiologia , Infecções por Acinetobacter/etiologia , Infecções por Acinetobacter/prevenção & controle , Bahamas , Estudos de Coortes , Infecção Hospitalar/etiologia , Infecção Hospitalar/prevenção & controle , Contaminação de Equipamentos , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Fatores de Risco , Estações do Ano , Sepse/etiologia , Sepse/microbiologiaRESUMO
OBJECTIVES: To determine risk factors for an increase in line-associated bloodstream infections (BSIs) in three pediatric intensive-care units at one hospital that recently had changed brands of needleless access device. DESIGN: Retrospective case-control studies; review of the units' infection control policies and procedures for accessing and replacing components of needleless access devices. SETTING: A community tertiary-care hospital's three pediatric intensive-care units. PATIENTS: Children in one of the three intensive-care units with a central venous catheter in place during January 1, 1995, through May 15, 1996, who developed laboratory-confirmed primary BSI. Children who had central venous catheters in place for >48 hours and who did not develop BSI were chosen randomly as controls. RESULTS: Eight patients met the case definition; they had 11 episodes of BSI. Multivariate analysis identified duration of catheterization and exposure to the IVAC first-generation needleless device as independent risk factors for BSI. Compared with patients from another pediatric intensive-care unit in which the IVAC device also was used but in which an increased BSI rate did not occur, patients from the unit with an increased BSI rate were more likely to receive intermittent (vs continuous) intravenous therapy through one or more lumens. In both units, the IVAC device valve component was replaced every 6 days, and the endcap used to cover the valve (when connected to an unused lumen) was replaced every 24 hours or after each access. The BSI rate returned to baseline after institution of a policy to replace the entire IVAC device, valve, and endcap every 24 hours. CONCLUSIONS: An increased risk of BSI was associated with use of the IVAC first-generation needleless device when replaced every 6 days. This increased risk may have been more pronounced in one pediatric intensive-care unit, because patients were more likely to receive intermittent intravenous therapy. Intermittent intravenous therapy or central venous catheter flushing practices may be important determinants of BSI risk.
Assuntos
Bacteriemia/etiologia , Cateterismo Venoso Central/efeitos adversos , Infusões Intravenosas/efeitos adversos , Adolescente , Adulto , Bacteriemia/prevenção & controle , Estudos de Casos e Controles , Cateterismo Venoso Central/instrumentação , Cateterismo Venoso Central/normas , Criança , Pré-Escolar , Feminino , Georgia , Humanos , Infusões Intravenosas/instrumentação , Infusões Intravenosas/normas , Unidades de Terapia Intensiva Pediátrica , Masculino , Análise Multivariada , Estudos Retrospectivos , Fatores de RiscoRESUMO
OBJECTIVE: To determine factors that correlate with increased antibiotic use among adult inpatients in Taiwan. DESIGN: Retrospective survey of medical records. SETTING: 14 acute-care hospitals (8 regional hospitals, 6 medical centers) in Taiwan. PARTICIPANTS: A systematic probability sample from each hospital, totaling 663 adult inpatients who were discharged or had died in early 1999. MEASUREMENTS: Infectious disease physicians at the 14 hospitals collected data from medical records regarding patient demographics, hospitalization, discharge diagnosis, and antibiotics received. RESULTS: A total of 447 (67%) patients received antibiotics for an overall rate of 813 antibiotic-days (number of days patients received each antibiotic)/1,000 patient-days. Both the proportion of beds in intensive care units ([ICUs] Pearson correlation coefficient [r], 0.67; 95% confidence interval [CI 95], 0.36-0.89; P<.01) and the proportion of patients admitted to surgical services (r, 0.66; CI 95, 0.20-0.88; P=.01) correlated with the mean patient rate of antibiotic-days/hospital-day (MPAUD). In contrast, we found no correlation between the proportion of patients who received antibiotics and the MPAUD. Using multiple linear regression, medical center status was the only independent predictor for increased MPAUD (regression coefficient [b], 0.15; CI 95, 0.05-0.24; P<.01). There was no correlation between pooled rates of antibiotic-days/hospital-day and any hospital demographic factors. First-generation cephalosporin (39%) and aminoglycoside (24%) use accounted for the majority of antibiotic-days. CONCLUSIONS: Antibiotic use is greater in medical centers than in regional hospitals and appears to be independent of surgical case mix or the proportion of ICU beds. Determination of multiple, independent measures of antibiotic use may be necessary to understand the relation between antibiotic use and resistance in hospital.
Assuntos
Antibacterianos/administração & dosagem , Revisão de Uso de Medicamentos , Sistemas de Medicação no Hospital/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Coleta de Dados , Resistência Microbiana a Medicamentos , Feminino , Hospitais/classificação , Humanos , Pacientes Internados , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , TaiwanRESUMO
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.
Assuntos
Coagulase/análise , Staphylococcus/enzimologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Bacteriemia/diagnóstico , Bacteriemia/microbiologia , Técnicas de Tipagem Bacteriana , Criança , Pré-Escolar , Feminino , Hospitais com 300 a 499 Leitos , Hospitais Comunitários , Humanos , Lactente , Recém-Nascido , Masculino , Auditoria Médica , Pessoa de Meia-Idade , Especificidade da Espécie , Staphylococcus/genética , Staphylococcus/isolamento & purificaçãoRESUMO
There are increasing public health concerns about antibiotics used in food-producing animals that may contribute to the development of resistance in human pathogens. Such resistance may be critical to human medicine when resistance develops to drugs that treat certain pathogens of which there is no good alternative therapy. We surveyed 10 farms, eight feed mills, and one animal drug distributor in Taiwan to determine the major antibiotics used in food-producing animals, and the extent of use of five drugs that may select for resistance to antibiotics that are critical for human medicine. The five animal drugs, and the resistance of human drug/class they may select for, included avoparcin (vancomycin/glycopeptides), avilomycin (ziracin/envirninomycins), enrofloxacin (ciprofloxacin/fluoroquinolones), virginiamycin (quinupristin and dalfopristin combination/streptogramins), and kanamycin (gentamicin/aminoglycosides). Tetracyclines were the class of antibiotic that was most widely used in the greatest amounts. Over the past 12 months, the number of farms, chicken feed mills, and pig feed mills, that have respectively reported the use of avoparcin was 1 (10%), 5 (63%), 0; avilomycin 0, 0, 3 (50%); enrofloxacin 4 (40%), 1 (13%), 3 (50%); virginiamycin 2 (20%), 5 (63%), 0; and kanamycin 3 (30%), 1 (13%), 1 (17%). We conclude that although the most commonly used antibiotics (ie tetracyclines) have little effect on human medicine, there is a widespread use of antibiotics that may select for critical forms of resistance in human pathogens in food-producing animals.
Assuntos
Doenças dos Animais/tratamento farmacológico , Resistência Microbiana a Medicamentos , Animais , Animais Domésticos , Galinhas , Humanos , Suínos , TaiwanRESUMO
For the first national surveillance of antibiotic resistance in Taiwan, we collected in 1998 from 22 hospitals (6 medical centers, 15 regional hospitals, and 1 local hospital) 3,211 isolates in all parts of the country. Besides 50 random successive isolates from inpatients, each hospital was requested to collect 25 isolates each from positive blood cultures, hospital-acquired infections, outpatients and the pediatric department. We re-speciated all the submitted specimens and determined their antibiotic susceptibility patterns. The most common isolates were Enterobacteriaceae (Escherichia coli, Klebsiella pneumoniae), Staphylococcus aureus, and Pseudomonas aeruginosa. Among hospital-acquired infections, Acinetobacter spp. were among those which accounted for over 10% of the isolates. The oxacillin resistance of S. aureus was 82% in isolates from hospital-acquired infections, and 40% from outpatients. Among Enterococcus spp., 85% were either E. faecalis or E. faecium. They were 14% resistant to vancomycin. Among gram-negative bacteria, K. pneumoniae and Acinetobacter baumanii were hospital-acquired isolates that were most clearly more resistant than community acquired isolates. This difference was less apparent in the case of Enterobacter cloacae, Serratia marcescens, and P. aeruginosa. These bacteria were generally more resistant from all sources. Fifty-one percent of Salmonella were resistant to ampicillin; however, these were all sensitive to ciprofloxacin. Isolates from the East were least resistant. Plotting the disc zone diameters of antibiotics within the susceptible range, we identified subpopulations with smaller diameters in the case of vancomycin against S. aureus, ciprofloxacin against E. coli, and ciprofloxacin against Salmonella spp. These findings represent one of the purposes of this surveillance as they may portend developing resistances which bear careful watching in the future.
Assuntos
Resistência Microbiana a Medicamentos , Ciprofloxacina/farmacologia , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/microbiologia , Enterococcus/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Humanos , Staphylococcus aureus/efeitos dos fármacos , Taiwan , Fatores de Tempo , Resistência a VancomicinaRESUMO
BACKGROUND AND PURPOSE: A large proportion of antibiotics used in hospitals is for surgical prophylaxis. We determined the prevailing practices and factors associated with the misuse of surgical antibiotic prophylaxis in hospitals in Taiwan. METHODS: In a systematic survey of the medical records of 629 patients from 14 hospitals who underwent clean or clean-contaminated surgery from September 1998 through March 1999, data on the timing and duration of, and reasons for, antibiotic use were collected and analyzed. RESULTS: Overall, 578 (92%) patients received antibiotics perioperatively; in 499 (79%) cases, antibiotics were used for surgical prophylaxis. Only 302 (61%) patients received prophylaxis within 1 hour before surgery. More than 70% of patients received more than 3 days of postoperative antibiotic prophylaxis. The most commonly used antibiotics were first-generation cephalosporins and aminoglycosides. Factors independently associated with inappropriately timed prophylaxis included surgery performed at a hospital with a greater proportion of intensive care unit beds (conditional odds ratio [OR] = 1.14 per 1% increase, 95% confidence interval [CI95%] 1.06-1.23; p < 0.01), surgery duration of at least 1 hour (OR = 0.40, CI95% 0.24-0.67; p < 0.01), orthopedic surgery (OR = 0.59, CI95% 0.36-0.98; p = 0.041), and cardiothoracic surgery (OR = 2.07, CI95% 1.14-3.77; p = 0.02). Risk factors for more than 3 days of prophylaxis included surgical placement of prosthetic material (OR = 2.26, CI95% 1.10-4.64; p = 0.03), the number of antibiotics used (OR = 1.99 per antibiotic, CI95% 1.26-3.13; p < 0.01), surgery duration of at least 1 hour (OR = 3.07, CI95% 1.45-6.51; p < 0.01), neurosurgery (OR = 4.57, CI95% 2.24-9.31; p < 0.01), and the use of oral antibiotics together with intravenous drugs (OR = 20.72, CI95% 10.72-40.07; p < 0.01). CONCLUSIONS: The results of this survey indicate that inappropriate use of surgical antibiotic prophylaxis is common in hospitals in Taiwan. Our results identify several problem areas, including incorrect timing, duration, and use of oral antibiotics for surgical prophylaxis, that require targeted physician education and public health interventions.
Assuntos
Antibioticoprofilaxia , Complicações Pós-Operatórias/prevenção & controle , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Uso de Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taiwan , Fatores de TempoRESUMO
The widespread use of antibiotics has been responsible for the development of numerous problems including the emergence of multidrug resistant bacteria, increased number of nosocomial- and community-acquired infections, less than optimal patient outcome, and increased health care costs. Of equal concern is the emergence of resistance in clinical isolates to antibiotics that were once considered "standard" with predictable in vitro susceptibility patterns. Such resistance has been especially notable in organisms that are commonly encountered in a variety of infections including, Streptococcus pneumoniae, Staphylococcus aureus. Enterococci, Klebsiella pneumoniae, and Escherichia coli. It is important for the clinical microbiology laboratory to provide the practicing clinician with accurate and timely antimicrobial susceptibility information which requires the application of standardized and approved in vitro testing methods. The laboratory also serves as a sentinel by maintaining an active monitoring and surveillance program in which current in vitro susceptibility patterns can be compared with local, regional, and national data bases.
Assuntos
Infecções Bacterianas/epidemiologia , Infecções Bacterianas/microbiologia , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/microbiologia , Resistência Microbiana a Medicamentos , Testes de Sensibilidade Microbiana/normas , Antibacterianos/efeitos adversos , Antibacterianos/uso terapêutico , Resistência Microbiana a Medicamentos/genética , Resistência Microbiana a Medicamentos/fisiologia , Uso de Medicamentos , Enterococcus , Humanos , Valor Preditivo dos Testes , Staphylococcus aureus , Streptococcus pneumoniaeAssuntos
Bacteriemia/epidemiologia , Sangue/microbiologia , Infecções Estafilocócicas/epidemiologia , Bacteriemia/microbiologia , Infecções Comunitárias Adquiridas/economia , Infecções Comunitárias Adquiridas/epidemiologia , Infecções Comunitárias Adquiridas/microbiologia , Gastos em Saúde , Humanos , Incidência , Recém-Nascido , Fatores de Risco , Infecções Estafilocócicas/microbiologia , Staphylococcus/isolamento & purificação , Zimbábue/epidemiologiaRESUMO
Escherichia coli LSUFS was injured either by freezing at -10 degrees C or by heating at 57 degrees C for 12 min. Surviving cells were recovered on nonselective tryptone-glucose extract agar and selective violet red bile agar supplemented with compounds that degrade hydrogen peroxide or block its formation. Various concentrations of the following compounds were tested: sodium pyruvate, 3,3'-thiodipropionic acid, catalase, ascorbic acid, potassium permanganate, sodium thioglycolate, dimethylsulfoxide, ethoxyquin, n-propyl gallate, alpha-tocopherol sodium metabisulfite, and ferrous sulfate. Sodium pyruvate and 3,3'-thiodipropionic acid, when added to either medium, significantly (P greater than 0.01) increased recovery of injured cells. More than 90% of the heat-injured cells and 40 to 90% of the freeze-injured cells failed to grow on unsupplemented tryptone-glucose extract agar. Supplementation of violet red bile agar increased recovery, but the counts remained considerably lower than the tryptone-glucose extract agar counts. The repair detection procedure of Speck et al. (M. Speck, B. Ray, R. Read, Jr., Appl. Microbiol. 29:549-550, 1975) was greatly improved by the addition of pyruvate or 3,3'-thiodipropionic acid. However, when this improved repair detection procedure was applied to foods, pyruvate-supplemented media showed some false-positives. We therefore recommend that 3,3'-thiodipropionic acid be used to supplement media in the repair detection procedure.
Assuntos
Escherichia coli/fisiologia , Peróxido de Hidrogênio/metabolismo , Catalase , Meios de Cultura , Escherichia coli/isolamento & purificação , Congelamento , Temperatura Alta , Propionatos , Piruvatos , Ácido PirúvicoRESUMO
In this study, we determined the internal cellular pH response of Leuconostoc mesenteroides and Lactobacillus plantarum to the external pH created by the microorganisms themselves or by lactic or acetic acids and their salts added to the growth medium. Growth of Leuconostoc mesenteroides stopped when its internal pH reached 5.4 to 5.7, and growth of L. plantarum stopped when its internal pH reached 4.6 to 4.8. Variation in growth medium composition or pH did not alter the growth-limiting internal pH reached by these microorganisms. L. plantarum maintained its pH gradient in the presence of either 160 mM sodium acetate or sodium lactate down to an external pH of 3.0 with either acid. In contrast, the DeltapH of Leuconostoc mesenteroides was zero at pH 4.0 with acetate and 5.0 with lactate. No differences were found between d-(-)- and l-(+)-lactic acid for the limiting internal pH for growth of either microorganism. The comparatively low growth-limiting internal pH and ability to maintain a pH gradient at high organic acid concentration may contribute to the ability of L. plantarum to terminate vegetable fermentations.
RESUMO
Early detection of vancomycin-resistant enterococci is important for preventing its spread among hospitalized patients. We surveyed the ability of eight hospital laboratories in and near Monterrey, Mexico, to detect vancomycin resistance in Enterococcus spp. and found that although laboratories can reliably detect high-level vancomycin resistance, many have difficulty detecting low-level resistance.
Assuntos
Antibacterianos/farmacologia , Infecção Hospitalar/microbiologia , Enterococcus/efeitos dos fármacos , Infecções por Bactérias Gram-Positivas/microbiologia , Laboratórios Hospitalares/normas , Vancomicina/farmacologia , Técnicas Bacteriológicas , Infecção Hospitalar/prevenção & controle , Resistência Microbiana a Medicamentos , Enterococcus/isolamento & purificação , Infecções por Bactérias Gram-Positivas/prevenção & controle , Humanos , México , Testes de Sensibilidade Microbiana , Microbiologia/normasRESUMO
To determine whether nosocomial infections due to Acinetobacter species have increased over the past 10 years and whether infections continue to have a pronounced seasonal variation, we analyzed infections reported by hospitals in the National Nosocomial Infections Surveillance System that performed adult and pediatric intensive care unit surveillance from 1987 through 1996. Overall, 3447 nosocomial acinetobacter infections were reported during 5,596, 156 patient-days. There was a yearly median of 7.2 infections (range, 5.0-10.5) per 10,000 patient-days and a downward trend in the rate of acinetobacter infections overall (P<.05) and of 2 major types of infection (P<.05): bloodstream infections (yearly median, 1.6 per 10, 000 central venous catheter-days; range, 1.3-2.9) and pneumonia (yearly median, 7.6 per 10,000 ventilator-days; range, 6.5-12.0). Throughout this period, average rates were significantly higher during July-October than during November-June for acinetobacter infections overall (8.0 vs. 5.2; P<.01) and for bloodstream infections (2.0 vs. 1.2; P<.01) and pneumonia (9.7 vs. 6.6; P<.01).
Assuntos
Infecções por Acinetobacter/epidemiologia , Infecção Hospitalar/epidemiologia , Humanos , Umidade , Incidência , Infecções por Pseudomonas/epidemiologia , Estações do Ano , Fatores de TempoRESUMO
Although nosocomial acquisition and subsequent colonization of vancomycin-resistant enterococci (VRE), an emerging international threat to public health, has been emphasized in the United States, colonization among nonhospitalized persons has been infrequently documented. In contrast, in Europe, colonization appears to occur frequently in persons outside the health-care setting. An important factor associated with VRE in the community in Europe has been avoparcin, a glycopeptide antimicrobial drug used for years in many European nations at subtherapeutic doses as a growth promoter in food-producing animals. In Europe, evidence suggests that foodborne VRE may cause human colonization. Although avoparcin has never been approved for use in the United States, undetected community VRE transmission may be occurring at low levels. Further studies of community transmission of VRE in the United States are urgently needed. If transmission with VRE from unrecognized community sources can be identified and controlled, increased incidence of colonization and infection among hospitalized patients may be prevented.
Assuntos
Antibacterianos/farmacologia , Enterococcus/efeitos dos fármacos , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/epidemiologia , Vancomicina/farmacologia , Ração Animal , Criação de Animais Domésticos , Animais , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Reservatórios de Doenças , Resistência Microbiana a Medicamentos , Europa (Continente)/epidemiologia , Microbiologia de Alimentos , Glicopeptídeos , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Saúde Pública , Estados Unidos/epidemiologiaRESUMO
The global nature of antimicrobial resistance and the failure to control the emergence of resistant organisms demand the implementation of a global surveillance program involving both developed and developing countries. Because of the urgent need for infection control interventions and for rapid distribution of information about emerging organisms, we initiated the International Network for the Study and Prevention of Emerging Antimicrobial Resistance (INSPEAR). Its main objectives are to serve as an early warning system for emerging antimicrobial-drug resistant pathogens, to facilitate rapid distribution of information about emerging multidrug-resistant pathogens to hospitals and public health authorities worldwide, and to serve as a model for the development and implementation of infection control interventions.
Assuntos
Controle de Doenças Transmissíveis , Resistência Microbiana a Medicamentos , Saúde Global , Serviços de Informação , Cooperação Internacional , HumanosRESUMO
A medium was developed for the differential enumeration of homofermentative and heterofermentative lactic acid bacteria. Essential components of the medium included fructose (14 mM), KH(2)PO(4) (18 mM), bromcresol green (as a pH indicator), and other nutrients to support growth. In agar medium, homofermentative colonies were blue to green, while heterofermentative colonies remained white. A total of 21 Lactobacillus, Pediococcus, Leuconostoc, and Streptococcus species were correctly classified with the medium.
RESUMO
Yeasts are an increasingly common cause of nosocomial bloodstream infections. Methods for their detection are many; controlled comparisons are few. The vented FAN aerobic blood culture medium has been shown to be superior to the standard BacT/ALERT aerobic medium for the detection of fungemia as well as bacteremia. The BACTEC selective fungal medium (FM) (BD Biosciences, Sparks, Md.) allowed detection of more episodes of fungemia than did a resin-containing medium with equal volumes of blood cultured. Therefore, we compared vented FAN to FM for the ability to recover fungi from the blood of patients who were at increased risk of having fungemia. From 5,109 cultures processed for which both FAN and FM bottles were adequately filled, fungi were recovered from 87 cultures. Of these, 47 were detected with both bottles, 12 were detected with FAN only, and 28 were detected with FM only (P < 0.05). FAN was the first bottle positive for 36 of the 47 cultures for which both bottles yielded the same fungus, whereas the FM bottle was the first bottle positive for 11 cultures (P < 0.001). A total of 54 episodes of fungemia were identified, with 40 detected by both media, 4 detected only by FAN, and 10 detected only by FM (P value, not significant). We conclude that the vented FAN aerobic bottle is comparable to the FM bottle for detection of episodes of yeast infection but has the added benefit of detecting bacteria.