Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “BACTEREMIA”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 433 records · Page 24Linked to original sources

Neutropenia is associated with bacteremia in patients infected with the human immunodeficiency virus.

Neutropenia occurs in approximately 17% of symptomatic patients infected with HIV. Results of studies have failed to demonstrate a consistent relationship between HIV-related neutropenia and the subsequent development of bacterial infections. This was a case control study to determine if HIV-related neutropenia was associated with increased rates of bacteremia. The experimental group was comprised of 29 patients infected with HIV that had an absolute neutrophil count less than 1000 cells/mm3 and were paired with 29 control subjects infected with HIV that had been matched for age, sex, CD4 count, and month and year of entry. The frequency of bacteremia was 12.6 per 100 patient months among the experimental group compared to a frequency of 0.87 per 100 patient months among the control group (relative risk [RR] = 14.9, P = 0.0027). Other independent risks for the development of bacteremia included central venous catheters (RR = 3.9, P = 0.03), with a trend toward increased risk for bacteremia in those patients who were intravenous drug users (RR = 3.8, P = 0.11), or who had infiltrative bone marrow disease (RR = 3.1, P = 0.11). Multivariate analysis demonstrated that neutropenia (odds ratio [OR] = 22.6, P = 0.028) and the presence of a central venous catheter (OR = 8.5, P = 0.026) were significant risks for bacteremia. These data suggest that neutropenia is a significant risk for the development of bacteremia in patients infected with HIV.

Analysis of Variance↗

Plasma cytokine determinations in emergency department patients as a predictor of bacteremia and infectious disease severity.

OBJECTIVE: To determine the predictive value of plasma interleukin (IL)-6 and tumor necrosis factor-alpha (TNF) measurements in assessing bacteremia and subsequent morbidity and mortality rates in emergency department patients. DESIGN: Prospective case series. SETTING: Emergency department and inpatient services of a large urban university hospital. PATIENTS: A total of 100 patients admitted through the emergency department with signs of infection and the presumptive diagnosis of bacteremia. INTERVENTIONS: Blood samples were collected for cytokine determinations. MEASUREMENTS AND MAIN RESULTS: IL-6 and TNF concentrations were measured by enzyme-linked immunosorbent assay (ELISA) in plasma samples obtained on patient admission to the emergency department. Patient's hospital course and culture results were documented by chart review. Severity of patient illness was estimated serially using the Acute Physiology and Chronic Health Evaluation (APACHE) II scoring system at entry into the study, and then again at 24 and 48 hrs. A quantified, subjective assessment of the severity of patient illness was recorded by the admitting physician in the emergency department. Multivariate logistic regression analysis using the variables of plasma IL-6 concentrations, TNF concentrations, APACHE II score at entry, physician assessment of illness severity, and patient age indicated that of these variables, only plasma IL-6 concentrations predicted bacteremia (p = .006) and death from infection (p = .009). A plasma IL-6 concentration > or = 2.0 ng/mL detected bacteremia with a positive predictive value of 72.7%, a sensitivity of 42.1%, and a specificity of 96.7%. Plasma TNF concentrations predicted mortality from all causes (p = .009) as did physician assessment of illness severity (p = .001). Increased APACHE II scores predicted the use of vasopressor medications (p = .002), length of hospital stay (p = .001), and subsequent increased APACHE II scores (p = .001) but did not predict bacteremia, death from infection, or death from all causes. Greater patient age predicted admission to the intensive care unit (p = .016). CONCLUSIONS: Measurement of plasma IL-6 concentrations in a population of emergency department patients with apparent bacterial infections predicted bacteremia and death from infection. The characteristics of the test indicated a potential use in selecting patients for the administration of novel therapies for sepsis.

Adolescent↗

A 25-year study of nosocomial bacteremia in an adult intensive care unit.

OBJECTIVE: To identify the organisms, their antibiotic susceptibility, and the associated focus on infection causing nosocomial bacteremia in patients in an adult intensive care unit (ICU) between 1971 and 1995. DESIGN: Prospective observational study. SETTING: A 12-bed general adult ICU in a 1,000-bed tertiary referral teaching hospital. PATIENTS: Four hundred eighty-six episodes of bacteremia involving 570 organisms in 425 patients. MEASUREMENTS AND MAIN RESULTS: Blood cultures taken from patients with suspected nosocomial infection were analyzed. Isolated organisms were identified, and their susceptibility to commonly used antibiotics was determined. Clinical details, including antibiotic treatment, were recorded for all patients. From 1986 to 1995, culture results of samples obtained from other sites were used to help identify the focus of infection causing bacteremia. All results were collected prospectively by clinical microbiologists. Between 1971 and 1990, the number of bacteremias and the relative frequency of isolation of individual organisms changed little, with Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Klebsiella species predominating. During 1991 to 1995, the number of bacteremias increased two-fold, largely attributable to increased isolation of Enterococcus species, coagulase-negative staphylococci, intrinsically antibiotic-resistant gram-negative organisms (particularly P. aeruginosa), and Candida species. The most commonly used antibiotics for the treatment of bacteremic patients throughout the 1970s were amoxicillin and gentamicin. After the introduction of cephalosporins in the early 1980s, their use increased progressively to equal that of gentamicin in the 1990s, whereas amoxicillin use decreased. Since the introduction of cephalosporins, increases in the antibiotic resistance of gram-negative organisms have been largely confined to an outbreak of gentamicin- and ceftazidime-resistant organisms caused by contaminated arterial pressure monitors during 1992 and 1993 and a two-fold increase in ceftazidime resistance of the Pseudomonas species. Gentamicin resistance of gram-negative aerobes remained unchanged (excluding the arterial pressure monitor outbreak), despite gentamicin being one of the most frequently prescribed antibiotics throughout the 25-yr period. Between 1986 and 1995, two thirds of all bacteremic organisms were cultured from intravascular catheters, which were designated as the focus of infection, 7% were secondary to gastrointestinal pathology, but only approximately 3% were secondary to wound, respiratory tract, or urinary tract infections. CONCLUSIONS: Bacteremias have become more frequent in the ICU, probably because of the increased use of intravascular catheters, which are the most frequent foci for bacteremic infection. The spectrum of organisms has changed, and this can be temporally related to the changes in the antibiotics prescribed. Gentamicin resistance of gram-negative organisms has not increased during a 25-yr period, despite being one of the most frequently prescribed antibiotics in the ICU.

Adult↗

Nosocomial bacteremia due to Acinetobacter baumannii. Clinical features, epidemiology, and predictors of mortality.

To study the possible predisposing factors, clinical features, molecular epidemiology, and factors affecting mortality associated with bacteremia due to Acinetobacter baumannii, we reviewed 87 episodes of A. baumannii bacteremia occurring in 79 patients hospitalized at 2 university tertiary care centers and 4 community-based hospitals during a recent 18-month period. Plasmid DNA analysis and analysis of genomic DNA with pulsed-field gel electrophoresis was performed to investigate possible epidemiologic relationship. All patients acquired their infections in the hospital, and no seasonal variation was observed. Among patients with A. baumannii bacteremia, 91% were hospitalized in an intensive care unit, 99% had indwelling vascular catheters, 81% received prior broad spectrum antimicrobial therapy, 70% were mechanically ventilated, and 47% had major surgical procedures. In 39 cases (45%) the infection was related to indwelling vascular access devices. Other infections included pneumonia (9%), tracheobronchitis (22%), meningitis (2%), and burn wound infections (4%). Septic shock occurred in 30% of patients. All isolates were multidrug resistant. Polymicrobial bacteremia was observed in 35% of cases. The crude mortality rate was 44%. Death was considered attributable to A. baumannii bacteremia in 15 (19%) patients. All patients with pneumonia as the primary site of infection died. Using multivariate analysis, we identified 3 independent predictors of mortality: the presence of a rapidly or ultimately fatal underlying disease (p = 0.0009), septic shock at the onset of bacteremia (p = 0.0013), and mechanical ventilation (p = 0.016). Epidemiologic typing revealed that 82 episodes were associated with different hospital outbreaks of infection, and only 7 episodes were due to epidemiologically unrelated strains.

Acinetobacter Infections↗

Coagulase-negative staphylococcal bacteremia in severely malnourished Jamaican children.

Immunosuppression increases the susceptibility to infection and changes the inflammatory response in children with severe protein-energy malnutrition. In this 5-year prospective study bacteremia was documented in 16% of 336 severely malnourished children, 2 to 34 months of age, who were hospitalized consecutively in the Tropical Metabolism Research Unit, Kingston, Jamaica. The 53 children had 60 episodes of nosocomial and community-acquired bacteremia with 69 blood isolates. Community-acquired bacteremia accounted for 72% (43 of 60) of bacteremic episodes. Thirty-five percent (24 of 69) of the strains were coagulase-negative staphylococci, 19% (13 of 69) were Staphylococcus aureus and 11% (8 of 69) were Streptococcus Group D. Seventeen episodes of coagulase-negative staphylococcal bacteremia were acquired in the community and 7 were nosocomial. These patients were more likely to have pneumonic consolidation than children with all other bacteremias combined (P < 0.02, Fisher's exact test). The bacteremia-related case fatality rate was 8% (5 of 60). Polymicrobial and Gram-negative septicemia were independent positive predictive factors for mortality when compared with single-agent and Gram-positive sepsis (P < 0.02). This 71% (49 of 69) prevalence of Gram-positive organisms suggests a change in the epidemiology from the predominant Gram-negative etiologies (76%) described in previous reports.

Bacteremia↗

Effect of antibiotic therapy on the outcome of outpatients with unsuspected bacteremia.

The records of 559 consecutive outpatient children with unsuspected bacteremia (467 Streptococcus pneumoniae) were reviewed. When compared with patients receiving oral or parenteral antibiotics, those patients who received no antibiotics at the initial visit were in follow-up: (1) less likely to be improved (32% vs. 86%, P < 0.01); (2) more likely to be febrile (75% vs. 28%, P < 0.01); (3) more likely to be hospitalized (67% vs. 22%, P < 0.01); (4) more likely to have persistent bacteremia (28% vs. 3%, P < 0.01); and (5) more likely to have new focal infections (13% vs. 5%, P < 0.01). Compared with patients receiving parenteral antibiotics at the initial visit, patients receiving oral antibiotics were in follow-up: (1) less likely to be improved (81% vs. 89%, P < 0.05); and (2) more likely to have persistent bacteremia (5% vs. 0%, P < 0.05). There was no statistical difference between patients receiving parenteral or oral therapy in the development of focal infections, although children with new focal infections receiving oral antibiotics more often had persistent or new positive cultures. No patients receiving parenteral antibiotics at the initial visit had positive blood or spinal fluid cultures at the follow-up visit. Analyses of the subgroups with (1) occult bacteremia with all organisms, (2) unsuspected bacteremia S. pneumoniae and (3) occult bacteremia with S. pneumoniae show results similar to those for the entire group.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗

Campylobacter bacteremia in children.

OBJECTIVE: To describe clinical and laboratory data for, and to propose pathogenesis and management of, children from impoverished communities with Campylobacter bacteremia. METHODS: A retrospective review of patient data generated from laboratory records in an urban tertiary care hospital in Soweto and a rural mission hospital in Eastern Transvaal, South Africa. Participants were 19 children presenting to either hospital with Campylobacter bacteremia. Clinical and laboratory data were collated. RESULTS: Nineteen children with Campylobacter bacteremia were identified; all isolates were Campylobacter jejuni. Sixteen (84%) had malnutrition; 13 of these were severely malnourished. Thirteen (68%) were febrile at the time of bacteremia. Four children (21%) did not have diarrhea. The case fatality rate was 16% and may not have been influenced by aminoglycoside administration. CONCLUSION: Malnourished children may be more likely to have gastrointestinal C. jejuni infection. Immunodeficiency and intestinal mucosal compromise secondary to malnutrition may render such children at increased risk of C. jejuni bacteremia and its consequences. C. jejuni bacteremia is potentially life-threatening and should be managed accordingly.

Aminoglycosides↗

Low risk of bacteremia in febrile children with recognizable viral syndromes.

BACKGROUND: Previous studies of occult bacteremia in febrile children have excluded patients with recognizable viral syndromes (RVS). There is little information in the literature regarding the rate of bacteremia in febrile children with RVS. OBJECTIVE: To determine the rate of bacteremia in children 3 to 36 months of age with fever and RVS. METHODS: We performed a retrospective analysis of all patients 3 to 36 months of age with a temperature > or =39 degrees C seen during a 5 1/2-year period in the Emergency Department of a tertiary care pediatric hospital. From this group those with a discharge diagnosis of croup, varicella, bronchiolitis or stomatitis and no apparent concomitant bacterial infection were considered to have an RVS. The rate of bacteremia was determined for those subjects with RVS who had blood cultures. RESULTS: Of 21,216 patients 3 to 36 months of age with a temperature > or =39 degrees C, 1347 (6%) were diagnosed with an RVS. Blood cultures were obtained in 876 (65%) of RVS patients. Of patients who had blood cultures, true pathogens were found in only 2 of 876 (0.2%) subjects with RVS [95% confidence interval (CI) 0.01, 0.8%]. The rate of bacteremia was 1 of 411 (0.2%) for subjects with bronchiolitis, O of 249 (0%) for subjects with croup, O of 123 (0%) for subjects with stomatitis and 1 of 93 (1.1%) for subjects with varicella. CONCLUSIONS: Highly febrile children 3 to 36 months of age with uncomplicated croup, bronchiolitis, varicella or stomatitis have a very low rate of bacteremia and need not have blood drawn for culture.

Age Factors↗

Pseudomonas aeruginosa bacteremia in children: analysis of trends in prevalence, antibiotic resistance and prognostic factors.

OBJECTIVE: To determine the factors predisposing to Pseudomonas aeruginosa bacteremia as well as the prevalence, source of infection, outcome and prognostic factors in pediatric patients. METHODS: Retrospective review of pediatric patients with P. aeruginosa bacteremia, at a large tertiary care hospital during a 6.5-year period. RESULTS: Seventy patients with P. aeruginosa bacteremia were identified. The annual rate of P. aeruginosa bacteremia remained unchanged during the study period. Antibiotic susceptibility remained unchanged except for two patients with extensive burns who developed resistant strains. Underlying diseases were malignancy (50%), prematurity (6%), burns (7%) and others (37%). The overall mortality associated with P. aeruginosa bacteremia was 20%. The fatality rate was higher among the young infants (compared with older children) and those who received previous antibiotic therapy (P = 0.02). Mortality rate was higher in nosocomial than in community-acquired infections (25% compared with 11.5%). The mortality rate of low birth weight and burns patients was significantly higher when compared with oncology patients or other patients, 75 and 40% compared with 11 and 19%, P = 0.01. Multiple regression analysis revealed a correlation only between the underlying disease and mortality (P = 0.02). In the oncology patients the only significant risk factor for mortality was absolute neutrophil count < or =0.1 x 10(9)/l (P = 0.06). CONCLUSION: P. aeruginosa bacteremia, although apparently not increasing in incidence and antibiotic resistance, is still a common serious complication in immunocompromised children with a high mortality rate. We conclude that the underlying disease is the main determinant of the clinical outcome.

Anti-Bacterial Agents↗

Interleukin-8 as a predictor of the severity of bacteremia and infectious disease.

The relationship between cytokines and sepsis has been studied frequently in the intensive care unit (ICU). However, the determination of cytokines in patients as they enter the emergency department (ED) would be more meaningful in predicting the outcome of infection. This study investigated plasma interleukin-8 in the ED as the predictor of bacteremia and sepsis. One hundred patients admitted through the ED with signs of systemic inflammatory response syndrome were studied. Plasma IL-8, IL-6, and tumor necrosis factor (TNF) were assayed by enzyme-linked immunosorbent assay. Patient's data were evaluated using the APACHE II scoring system as predictive factors of morbidity and mortality. Plasma IL-8 (149 pg/mL) detected bacteremia with a positive predictive value of 90.9% and a specificity of 98.7%. Results indicated that the odds ratios (ORs) of bacteremia were 24.78 (P < 0.01, CI = 2.27-270.8), 5.42 (P < 0.05, CI = 1.37-21.4), and 6.05 (P < 0.05, CI = 1.36-26.8) for IL-8, IL-6, and APACHE II, respectively. Occurrence of bacteremia was highly correlated with increases in plasma IL-8 (P < 0.01). IL-8 (OR = 8.25, CI = 1.03-65.9) and APACHE II scores (OR = 12.6, CI = 2.24-70.4) were found to be significantly better predictive factors of mortality (P < 0.01) than IL-6 (OR = 3.60, CI = 0.57-22.7), TNF (OR = 0.24, CI = 0.01-11.0) and age (OR = 1.02, CI = 0.98-1.06). During bacteremia, IL-8 also correlated well with patient use of a ventilator (P < 0.01, OR = 2.43, CI = 2.41-311.19), use of vasopressors (P < 0.05, OR = 2.67, CI = 1.79-370.78), length of stay in the hospital (P < 0.01, OR = 3.14, CI = 1.87-988.31), and stay in the ICU (P < 0.01, OR = 2.51, CI = 2.98-449.80). Measuring IL-8 on patients in the ED with apparent bacterial infections appears to be a reliable predictor of bacteremia and the severity of disease.

APACHE↗

A pilot study of the predictive value of plasma tumor necrosis factor alpha and interleukin 1 beta for Streptococcus pneumoniae bacteremia in febrile children.

OBJECTIVE: To determine the value of tumor necrosis factor alpha (TNF) and interleukin 1 beta (IL1) levels in predicting Streptococcus pneumoniae bacteremia in nontoxic-appearing, febrile children who do not have a bacterial source for their fever on physical examination. METHODS: A prospective, nested case-control study was conducted in a children's hospital ED. All febrile children < 3 years old who were believed to be immunocompetent and not in shock, had no obvious bacterial source for their fever on physical examination, and had a blood culture obtained were eligible. Plasma obtained at the time of the blood culture was available for analysis by enzyme-linked immunosorbent assays for TNF and IL1. Children who had positive blood cultures for Streptococcus pneumoniae were the cases. The controls were selected from children who had negative blood cultures. RESULTS: During a 1-year period, 12 cases and 65 controls were identified. There was no significant difference in age, height or duration of fever, or illness acuity between the groups. The following were used as threshold values for positive test: white blood cell (WBC) count > 15.0 x 10(9) cells/L, TNF > 21.5 ng/mL, and IL1 > 9.0 ng/mL. Using an estimated prior probability of bacteremia of 4%, the positive predictive value (PPV) and the negative predictive value (NPV) for bacteremia were 11.7% and 98.6% using the WBC count, 11.1% and 98.6% using the IL1 level, and 9.0% and 98.9% using the TNF level. The combination of WBC count with either TNF or IL1 gave an NPV of 100%, with PPVs of 8.5% for TNF and 9.9% for IL1. CONCLUSIONS: Like the WBC count, TNF and IL1 are good negative but poor positive predictors of Streptococcus pneumoniae bacteremia in nontoxic-appearing, febrile children. At present, the addition of plasma TNF or IL1 levels would add little to emergency physicians' ability to predict Streptococcus pneumoniae bacteremia. However, as the quantification of these cytokines becomes more rapid, available, and standardized, and more knowledge of TNF and IL1 levels during various illnesses is gained, their utility in the clinical setting for ruling out bacteremia should be further assessed.

Bacteremia↗

Clinical impact of persistent Bartonella bacteremia in humans and animals.

Bartonella spp. are emerging vector-borne pathogens that cause persistent, often asymptomatic bacteremia in their natural hosts. As our knowledge progresses, it appears that chronic infection may actually predispose the host to mild, insidious nonspecific manifestations or induce, in selected instances, severe diseases. Persistent asymptomatic bacteremia is most common in animals that serve as the main reservoir for the specific Bartonella. In humans, these organisms are B. bacilliformis and B. quintana. Other Bartonella species, for which humans are not the natural reservoir, tend to cause persistent bacteremia only in immunodeficient individuals. In some of these individuals, endothelial cell proliferation may create lesions such as bacillary angiomatosis or bacillary peliosis. In cats, bacteremia of variable level and continuity may last for years. Some strains of B. henselae may induce clinical manifestations, including fever, mild neurological signs, reproductive disorders, whereas others do not induce clinically obvious disease. Reproductive disorders have also been reported in mice experimentally infected with B. birtlesii. Finally, canids constitute the most interesting naturally occurring animal model for the human disease. Like immunocompetent people, healthy dogs only occasionally demonstrate long-term bacteremia when infected with Bartonella spp. However, some dogs develop severe clinical manifestations, such as endocarditis, and the pathologic spectrum associated with Bartonella spp. infection in domestic dogs is rapidly expanding and resembles the infrequently reported clinical entities observed in humans. In coyotes, persistent bacteremia is more common than in domestic dogs. It will be of interest to determine if coyotes develop clinical or pathological indications of infection.

Animals↗

[A clinical study of bacteremia in the last fifteen years].

Between 1976 and 1990, 208 cases of bacteremia in our department were studied. Community acquired bacteremias were only 18 (8.7%) cases. Bacteremias, particularly caused by Gram positive organisms, increased significantly after 1981, compared with the first five years. It was related to the marked increase in cases of venous access devices and less sensitivity of the Gram positive organisms to the new cephem antibiotics. In the study, 144 (69.2%) cases were eradicated. Severe underlying diseases or complication of pneumonia influenced the eradication rate of bacteremia. Bacteremia caused by methicillin resistant Staphylococcus aureus or Pseudomonas aeruginosa showed poor prognosis. The average duration from onset to death, was 5.1 days. Forty cases (62.5%) died within 3 days. Among the 201 cases, leukocytosis (WBC greater than 10,000/mm3) was present in 38.3%, while leukopenia (WBC less than 1000/mm3) in 25.3%. Eradication rate between the two groups was not significant. CRP was elevated (greater than 8.5 mg/dl) in 63.5%. The prognosis of this group was significantly poor. Elevation of serum bilirubin was also related with increase of mortality. According to these results, empiric therapy before the isolation of organisms is the most important strategy for treatment of bacteremia.

Adolescent↗

[Targeted bacteremia surveillance throughout a year--comparison of community-acquired and hospital-acquired infection].

To keep an eye on severe nosocomial infection and to evaluate the clinical difference of blood-stream infection between community-acquired and hospital-acquired infection, a survey of blood culture was performed in National Tokyo Medical Center from the period between November 2000 and October 2001. There were 252 episodes detected in 219 patients (80 community-acquired episodes in 80 patients and 172 hospital-acquired episodes in 139 patients). The three most common foci of infection/pathogens were as follows: in the community-acquired cases; urinary tract, pneumonia, infective endocarditis/Escherichia coli, viridant group of streptococci, Streptococcus pneumoniae, and in the hospital-acquired cases; intra-venous catheter, urinary tract, neutropenia-related bacteremia/Staphylococcus aureus, coagulase negative Staphylococcus, Enterococcus. Fifteen patients with community-acquired bacteremia and 37 patients with hospital-acquired bacteremia had been died within a month of the episode; the mortality was not significantly different between the both. The average of peak serum concentrations of C-reactive protein during the episodes of community-acquired bacteremia was higher than that of hospital-acquired bacteremia. These findings probably show that life threatening bloodstream infections seemed to be more common in the community. The rate of nosocomial bacteremia was approximately 1%, and no outbreak was observed during the period. Targeted bacteremia surveillance is maybe useful and efficient method to detect severe hospital-acquired infections.

Adolescent↗

A glycoconjugate vaccine for Neisseria meningitidis induces antibodies in human infants that afford protection against meningococcal bacteremia in a neonate rat challenge model.

The functional activities of serum samples from human infants immunized with a glycoconjugate vaccine for Neisseria meningitidis serogroup C were assessed in a complement-mediated antibody-dependent serum bactericidal assay (SBA) and in a neonate rat model of protection from bacteremia. Selective serum samples from individual human infants were combined to make a panel of 11 serum pools to obtain a sufficient volume for testing. Each pool was assayed (i) for the anti-N. meningitidis serogroup C capsular polysaccharide (PS) immunoglobulin G (IgG) concentration as determined by reactivity in a direct-binding enzyme-linked immunosorbent assay, (ii) for bactericidal activity against N. meningitidis serogroup C strain C11, and (iii) for the ability to reduce bacteremia after passive transfer into a neonate rat model. Representative serum samples from infants who were not previously immunized with any N. meningitidis serogroup C vaccine served as a negative control. The prepared serum pools ranged in antibody concentration from 0.18 to 17.31 micro g of IgG specific for N. meningitidis serogroup C PS per ml. For this serum panel, a direct relationship between concentrations of anti-N. meningitidis serogroup C PS-specific IgG and serum SBA titers (r = 0.9960) was observed. Passive transfer to neonate rats demonstrated the ability of postimmunization serum samples to significantly reduce (> or =2-log(10) reduction compared to control animals) the level of bacteremia following a challenge. Of 79 neonate rats that received > or =0.031 micro g of human infant anti-N. meningitidis serogroup C PS IgG, 75 (94.9%) had a > or =2-log(10) reduction in bacteremia, whereas of the animals that received <0.031 micro g of antigen-specific IgG, 10.3% (4 of 39 rats) showed a > or =2-log(10) reduction in bacteremia. It was concluded that the anti-N. meningitidis serogroup C PS IgG antibody induced by this glycoconjugate vaccine had in vitro functional activity (as determined by a SBA) and also afforded protection against meningococcal bacteremia in an animal model.

Animals↗

Recurrent Escherichia coli bacteremia.

Escherichia coli is the most common gram-negative organism associated with bacteremia. While recurrent E. coli urinary tract infections are well-described, recurrent E. coli bacteremia appears to be uncommon, with no episodes noted in multiple series of patients with gram-negative bacteremias. We report on 5 patients with recurrent bloodstream infections identified from a series of 163 patients with E. coli bacteremia. For each patient, the isolates from each episode were analyzed by pulsed-field gel electrophoresis (PFGE) and ribotyping and for the presence of E. coli virulence factors. For each of four patients, the index and recurrent episodes of bacteremia represented the same strain as defined by PFGE, and the strains were found to carry one or more virulence factors. The remaining patient, with two episodes of bloodstream infection separated by a 4-year interval, was infected with two isolates that did not carry any virulence factors and that were clonally related by ribotype analysis but differed by PFGE. All five patients had either a local host defense defect (three patients) or impaired systemic defenses (one patient) or both (one patient). Thus, recurrent E. coli bacteremia is likely to represent a multifactorial process that occurs in patients with impaired host defenses who are infected with virulent isolates.

Adult↗

Comparative study of bacteremias caused by Enterococcus spp. with and without high-level resistance to gentamicin. The Grupo Andaluz para el estudio de las Enfermedades Infecciosas.

A prospective, multicenter study was carried out over a period of 10 months. All patients with clinically significant bacteremia caused by Enterococcus spp. were included. The epidemiological, microbiological, clinical, and prognostic features and the relationship of these features to the presence of high-level resistance to gentamicin (HLRG) were studied. Ninety-three patients with enterococcal bacteremia were included, and 31 of these cases were caused by HLRG (33%). The multivariate analysis selected chronic renal failure, intensive care unit stay, previous use of antimicrobial agents, and Enterococcus faecalis species as the independent risk factors that influenced the development of HLRG. The strains with HLRG showed lower levels of susceptibility to penicillin and ciprofloxacin. Clinical features (except for chronic renal failure) were similar in both groups of patients. HLRG did not influence the prognosis for patients with enterococcal bacteremia in terms of either the crude mortality rate (29% for patients with bacteremia caused by enterococci with HLRG and 28% for patients not infected with strains with HLRG) or the hospital stay after the acquisition of enterococcal bacteremia. Hemodynamic compromise, inappropriate antimicrobial therapy, and mechanical ventilation were revealed in the multivariate analysis to be the independent risk factors for mortality. Prolonged hospitalization was associated with the nosocomial acquisition of bacteremia and polymicrobial infections.

Adult↗

Comparison of a repetitive extragenic palindromic sequence-based PCR method and clinical and microbiological methods for determining strain sources in cases of nosocomial Acinetobacter baumannii bacteremia.

Using a repetitive extragenic palindromic PCR (REP-PCR), we genotypically characterized strains causing nosocomial Acinetobacter baumannii infections and analyzed the source of bacteremia in 67 patients from an institution in which infections by this bacterium were endemic. Six different genotypes were found, including 21, 27, 3, 9, 3, and 4 strains. The probable source of bacteremia, according to clinical and/or microbiological criteria, was known in 42 patients (63%): respiratory tract (n = 19), surgical sites (n = 12), intravascular catheters (n = 5), burns (n = 3), and urinary tract (n = 3). The definite source of bacteremia, according to REP-PCR, could be established in 30 (71%) out of the 42 patients with strains from blood and other sites; in these cases clinical and microbiological criteria for the source of bacteremia were thus confirmed. In the remaining 12 patients (29%) the probable source was refuted by the REP-PCR method. The definite sources of bacteremia according to genotype were as follows: respiratory tract in 13 patients (31%), surgical sites in 8 (19%), intravascular catheters in 4 (9%), burns in 3 (7%), and urinary tract in 2 (5%). A comparison of strains from blood cultures and other sites with regard to their REP-PCR and antimicrobial resistance profiles was also made. Taking the REP-PCR as the "gold standard," the positive predictive value of antibiotype was 77% and the negative predictive value was 42%. In summary, the utility of the diagnosis of the source of nosocomial A. baumannii bacteremia using clinical and/or microbiological criteria, including antibiotyping, is limited, as demonstrated by REP-PCR.

Acinetobacter Infections↗