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The article reports on the market approval issued by the U.S. Food and Drug Administration (FDA) to the Accelerate PhenoTest BC Kit developed to identify pathogens such as bacteria and yeast in blood.

Clinical signs and symptoms of central nervous system (CNS) infections in neonates are often nonspecific. Therefore, cerebrospinal fluid (CSF) analysis is performed to diagnose CNS infections. Data on combined microbiological results and their correlation with biochemical characteristics in CSF and blood in infants younger than 90 days are limited. This study provides an overview of microbiological test results, CSF- and hematological characteristics among infants with a clinically suspected CNS infection.This retrospective study included infants younger than 90 days, with a clinically suspected CNS infection who underwent a diagnostic lumbar puncture between January 2012 and January 2014. Data on the presence of microbiological pathogens in CSF, CSF inflammation markers (white blood cell [WBC] counts, protein levels and glucose CSF/serum ratio) and blood inflammatory responses (WBC count, C-reactive protein [CRP], neutrophil percentage) were collected by reviewing patient files.We included data from 576 infants (median age 12.5 days, interquartile range, 6-27 days) of whom 383 (66.5%) were born prematurely. In total, 16 bacterial pathogens (3.0%) and 21 viruses (5.5%) were detected in CSF. Escherichia coli was detected in 5 cases (1.0%), Enterovirus was detected in 12 cases (3.1%). Leucocytosis in CSF was associated with identification of a pathogen in CSF. Increased CRP was associated with the identification of a bacterial pathogen in CSF.Bacterial or viral pathogens were only identified in a small proportion of infants with a clinically suspected CNS infection. Leucocytosis in CSF was associated with CNS infection in infants. An increased CRP was indicative of bacterial meningitis.

Objectives: Blood cultures are performed in the emergency room when sepsis is suspected, and a cohort of patients is thereby identified. The present study investigated the outcomes (mortality and length of hospital stay) in this group following an emergency medical admission., Methods: Prospective assessment of all emergency medical admissions presenting to the emergency department at St James's Hospital, Dublin, over an 11-year period (2002-2012) was carried out. Outcomes including 30-day in-hospital mortality and length of stay were explored in the context of an admission blood culture. Generalized estimating equations, logistic or zero-truncated Poisson multivariate models were used, with adjustment for confounding variables including illness severity, comorbidity, and chronic disabling disease, to assess the effect of an urgent blood culture on mortality and length of stay., Results: A total of 60 864 episodes were recorded in 35 168 patients admitted over the time period assessed. Patients more likely to undergo blood cultures in the emergency department were male, younger, and had more comorbidity. Univariate and multivariate analyses showed that those who had a blood culture, irrespective of result, had increased mortality and a longer in-hospital stay. This was highest for those with a positive culture, irrespective of the organism isolated., Conclusion: A clinical decision to request a blood culture identified a subset of emergency admissions with markedly worse outcomes. This patient cohort warrants close monitoring in the emergency setting.

Objective: The objective of this study was to validate a previously published clinical decision rule for predicting a positive blood culture in emergency department (ED) patients with suspected infection on the basis of major and minor criteria and a total score (Shapiro et al., J Emerg Med, 2008; 35:255-264)., Methods: This is a retrospective matched cohort study of adult ED patients with blood cultures obtained from 1 January 2011 through to 31 December 2011. ED patients with blood culture-confirmed bacteremia were matched 1 : 3 with patients with negative cultures. The outcome was 'true bacteremia'. Data on clinical history, comorbid illnesses, physical observations, and laboratory tests were used to evaluate the application of the clinical decision rule. We report the sensitivity, specificity, and area under the curve., Results: Among 1526 patients, 105 (6.9%) patients were classified with true bacteremia. The sensitivity of the prediction rule was 94% (95% confidence interval, 88-98%) and the specificity was 48% (95% confidence interval, 42-53%). The area under the receiver-operating characteristics curve was 0.83., Conclusion: The clinical decision rule performed well in our ED setting and is likely to be a useful supplement to clinical judgment.

Objectives: Blood culture (BC) is one of the most commonly used microbiological tests in the paediatric emergency department (PED) despite its lack of immediate diagnostic utility. Our objectives were to uncover the reasons for BC in the PED, to review adherence to the current protocol for this technique, and to analyse the diagnostic yield (DY) of BC in localized bacterial infections., Patients and Methods: Retrospective study including patients younger than 18 years with a BC obtained in the PED of a tertiary care hospital in 2011. Patients with bacteraemia risk factors (immunosuppressant condition, long-term vascular catheter, prosthetic valve or ventriculoperitoneal shunt, and hospitalization or aggressive diagnostic or therapeutic procedure in the previous week) were excluded., Results: Two thousand and sixty-two BCs were included. Fever without source (FWS) (34.3%) and pneumonia (10.1%) were the main indications for BC. Twenty-five per cent of BCs did not adhere to protocol: FWS (115 cases), mononucleosic syndrome (83 cases) and acute gastroenteritis (78 cases) represented half of these. The global DY by BC was 2.0%. Streptococcus pneumoniae was the main isolated microorganism (41.4%) and pneumonia was the main associated pathology (22%). All of the BCs with non-adhered-to protocol were negative. All of the BCs obtained for noncomplicated bacterial skin and soft tissue infection were negative., Conclusion: FWS is the main reason for BC in the PED. One-quarter of the BCs were not indicated, with the DY null in these cases. Due to the low DY in certain localized bacterial infections, a strict individualized ordering of BC in these cases should be considered.

Objective: To review the accuracy of the pediatric consensus definition of sepsis in term neonates and to determine the definition of neonatal sepsis used., Study Selection: The review focused primarily on pediatric literature relevant to the topic of interest., Conclusions: Neonatal sepsis is variably defined based on a number of clinical and laboratory criteria that make the study of this common and devastating condition very difficult. Diagnostic challenges and uncertain disease epidemiology necessarily result from a variable definition of disease. In 2005, intensivists caring for children recognized that as new drugs became available, children would be increasingly studied and thus, pediatric-specific consensus definitions were needed. Pediatric sepsis criteria are not accurate for term neonates and have not been examined in preterm neonates for whom the developmental stage influences aberrations associated with host immune response. Thus, specific consensus definitions for both term and preterm neonates are needed. Such definitions are critical for the interpretation of observational studies, future training of scientists and practitioners, and implementation of clinical trials in neonates.

Objective: To characterize the descriptive and molecular epidemiology of Acinetobacter baumannii in our hospital., Design: Longitudinal analysis of electronic microbiology laboratory records and isolates., Setting: A 1,500 bed public teaching hospital in the Miami area., Patients: Consecutive patients with A. baumannii from January 1994 to December 2011., Interventions: None, Measurements and Main Results: : Data on all A. baumannii isolates were clustered at the patient level, and the first isolate per single patient was determined. Yearly trends were analyzed based on carbapenem susceptibilities and originating units for all first isolates and first blood isolates per unique patient. Additionally, carbapenem nonsusceptible isolates frozen in the microbiology laboratory since 1998 were retrieved and evaluated using polymerase chain reaction and randomly amplified polymorphic DNA techniques. A total of 9,334 A. baumannii isolates were detected, of which 4,484 isolates (48%) were identified as first positive isolates per unique patient. Most of the burden of disease was located in the ICUs (odds ratio, 2.64 [95% CI, 2.17-3.22]; p < 0.0001) and in the adult wards (odds ratio, 3.867 [95% CI, 2.71-5.52]; p < 0.0001). Respiratory specimens constituted the most frequent source (49%; odds ratio, 1.619 [95% CI, 1.391-1.884]; p < 0.0001). Of the 4,484 first isolates, 846 isolates (18.9%) were carbapenem nonsusceptible and 3,638 isolates (81.1%) were carbapenem susceptible. Over the years, the number of carbapenem nonsusceptible isolates increased, whereas the number of carbapenem susceptible decreased (p < 0.0001). The trauma ICU had the highest burden of carbapenem nonsusceptible first isolates (205 of 846; 24.2%). Seven clones were discovered among 144 carbapenem nonsusceptible isolates; one of these clones was found from 1999 to 2005. OXA-23 and OXA-40 were identified in 96 and 13 isolates, respectively. One isolate harbored a novel CTX-M-115 enzyme., Conclusions: This constitutes the largest experience with A. baumannii reported to date from a single center. Half of all isolates were respiratory specimens and were from adult ICUs, especially trauma. Even though this was a polyclonal process, a single clone was identified in the hospital through a 6-year span.

Objective: Overwhelming postsplenectomy infection progresses rapidly and shows unacceptably high mortality even when treated with optimal antibiotics. Recent reports have described beneficial effects of intravenous immunoglobulin in sepsis. However, the underlying mechanisms, especially the roles of the pathogen-specific antibody fraction in intravenous immunoglobulin, remain unclear. We investigated the effects of intravenous immunoglobulin on overwhelming postsplenectomy infection and the role of pathogen-specific antibody., Design: Prospective, controlled, and randomized animal study., Setting: University laboratory., Subjects: Male C57BL/6JJcl mice., Interventions: Mice underwent splenectomy or a sham operation at 8 weeks old. At 4 weeks after the operation, mice were injected intravenously with 106 colony-forming units pneumococcus. Intraperitoneal injection of 300 mg/kg IV immunoglobulins was conducted simultaneously with infection. Specific antibody-depleted IV immunoglobulin prepared using immunoprecipitation was also injected into the animals., Measurements and Main Results: IV immunoglobulin markedly improved splenectomized mice survival. Removal of pneumococcus-specific antibody canceled it completely. Fluorescence microscopy results indicated significantly increased phagocytosis of antibody-bound bacteria in the livers of splenectomized mice treated with intact IV immunoglobulins. Immunomodulation, including suppression of marginal zone B-cell activation, was induced by IV immunoglobulin., Conclusions: IV immunoglobulin showed a significantly protective effect on overwhelming postsplenectomy infection via enhancement of specific antibody-mediated phagocytosis in the liver. Specific antibody, more than immunological modulation, is crucial for effects of IV immunoglobulin on overwhelming postsplenectomy infection.

Pelvis is a rare location of the hematogeneous osteomyelitis during the newborn period. Successful cure of osteomyelitis during the newborn period is dependent on a fast and true diagnosis and on sufficient treatment. In this case report, iliac osteomyelitis of a newborn that was clinically suspected on the fifth day, was diagnosed radiologically and was found to be caused by methicillin-sensitive Staphylococcus aureus, is presented. According to our knowledge, this is the youngest osteomyelitis case in the literature and the third presented iliac osteomyelitis case of the newborn period.

Osteomyelitis is an uncommon infection that is considered to be a childhood disease. Diagnosis is frequently delayed, as it is a very rare condition and also because of its variable presentation. After an accurate diagnosis and treatment, the outcome is favorable in children. We present one case without recent previous infection, antecedent trauma, or penetrating injury, illustrating the difficulties in diagnosis. Nontraumatic osteomyelitis of the patella should be regarded as a rare hematogenous infection. A high index of suspicion should be addressed for early recognition. Study design is level of evidence: level IV.

Background: Fever is a common reason children present to the emergency department. The goal of this study was to determine the rates and the etiology of bacterial infection in children younger than 2 months during the vaccination era., Methods: This is a retrospective chart review performed at a tertiary care hospital. Electronic medical records were used to identify patients who had a workup for fever/sepsis in the emergency department. The search was limited to identifying only children younger than 60 days., Results: A total of 207 patients satisfied the inclusion/exclusion criteria. In children younger than 28 days, the blood culture-positive rate was 2.7% (range, 0.0%-6.4%), the urine culture-positive rate was 10.7% (range, 3.5%-17.8%), and the cerebrospinal fluid-positive rate (excluding enteroviral infections) was 0% (range, 0.0%-3.9%). In children 29 to 60 days, the blood culture-positive rate was 1.5% (range, 0.0%-3.6%), urine culture-positive rate was 8.5% (range, 3.7%-13.3%), and the cerebrospinal fluid-positive rate (excluding enteroviral infections) was 1.7% (range, 0.0%-5.0%). Urinary tract infections due to Escherichia coli were very common, whereas no cases of Haemophilus influenzae and one case of Streptococcus pneumoniae were detected., Conclusions: Urinary tract infections due to E. coli are very common in this age group. The classic pathogens H. influenzae and S. pneumoniae were essentially nonexistent in this study possibly because of herd immunity obtained through current vaccination practices.

Objective: Blood culture contamination rates (CRs) in emergency departments (EDs) vary from 1% to 9% in previous studies. High CRs cause unnecessary admissions, antibiotics, and costs. Different measures have been tried to improve CR. This study sought to determine the ED CR at Arkansas Children's Hospital (ACH) and evaluate an educational intervention., Design: A slide presentation of the ACH's blood culture collection procedure was made. The ED nursing staff viewed this individually and demonstrated the procedure on a mock extremity. Data before (from June 1 to November 30, 2007; PRE) and after (from February 1 to July 31, 2008; POST) intervention regarding blood cultures positive for organism submitted to the ED and any descriptive data were collected retrospectively. Descriptive statistics described the CR, positivity rate (PSR), and pathogen rate (PR). Frequent collectors were identified as those submitting more than 72 blood cultures during PRE and during POST. Contamination rate in frequent collectors was independently assessed for improvement. This study was approved by the institutional review board of the University of Arkansas for Medical Sciences., Results: Positivity rate during PRE was 6.8% (n = 15; 95% confidence interval [CI], 2.9-10.7); 114 were contaminants (CR, 5.0%; 95% CI, 1.04-8.98) and 40 were pathogens (PR, 1.8%; 95% CI, ± 4.28). Positivity rate during POST was 6.3% (n = 157; 95% CI, 2.6-10.0); 124 were contaminants (CR, 4.9%; 95% CI, 1.14-8.66) and 33 were pathogens (PR, 1.4%; 95% CI, ± 4.22). For both PRE and POST, contaminants represented 74% or greater of all the positives and more than 75% of contaminants occurred in patients 0 to 36 months old.Contamination rates of individual practitioners ranged from 0% to 17% (PRE) and from 0% to 21% (POST). The CR was lower in POST for samples submitted from frequent collectors (practitioners submitting >72 blood cultures per study period, n = 6), was evaluated separately, and found to improve in POST (from 4.1% to 2.7%). A t test for matched samples for these samplers revealed a significant decrease in the POST period, P = 0.03., Conclusions: The CR in the ACH ED for peripherally drawn blood cultures is approximately 5% monthly with less than 2% PR. For each culture positive for organism, the chance of contamination is 75% or higher. An intervention emphasizing the appropriate technique, monitored training, and improved CR of a group of frequent collectors is warranted.

Background: Blood cultures (BCs) are used to diagnose bacteremia in febrile children. False-positive BCs increase costs because of further testing, longer hospital stays, and unnecessary antibiotic therapy. Data from a study at our hospital showed the emergency department consistently exceeded established guidelines of 2% to 4%. A phlebotomy policy change was made whereby BC had to be obtained by a second venipuncture and no longer obtained during insertion of intravenous catheters., Methods: A descriptive study compared preintervention and postintervention blood culture contamination (BCC) rates. A BC was considered contaminated if a single culture grew coagulase-negative staphylococci, diphtheroids, Micrococcus spp, Bacillus spp, or viridans group streptococci. Patients with indwelling central lines or who grew pathogenic bacteria were excluded., Results: Preintervention BCC was 120 (6.7% [SD, 2.3%]) of 1796. Postintervention BCC was 29 (2.3%, [SD, 0.8]) of 1229 with odds ratio of 2.96 (confidence interval, 1.96-4.57; P = 0.001). The most common contaminant was coagulase-negative staphylococcus, 21 (72%) of 120, followed by viridans streptococcus, 3 (10%) of 29, which was not significantly different between intervention periods. Before intervention, 44 patients were called back to the emergency department, and 25 were admitted because of BCC. After intervention, a total of 9 patients were called back, and 5 were admitted. The decrease in unnecessary hospitalization was statistically significant (P < 0.05)., Conclusions: The new policy significantly reduced BCC rates, thereby decreasing unnecessary testing and hospitalizations. Coagulase-negative staphylococci and viridans streptococci remain the most common BC contaminants. Further research should focus on additional interventions to reduce BCC.

The aim of our study was to determine the usefulness of pneumococcal urinary antigen (UA) collected in the emergency department (ED) for the microbiologic diagnosis of community-acquired pneumonia (CAP) in HIV patients and to compare it with other diagnostic tests. Prospective study from 1 January 2007 to 31 December 2008 included HIV-infected patients admitted at the ED with respiratory symptoms and who were diagnosed of CAP. UA, two blood cultures and sputum sample for culture determination were collected from every patient. Sixty-four patients were included. The mean age was 42 years. A total of 31 (48%) UA tests, 12 (19%) blood cultures and 21 (33%) sputum cultures tested positive. A microbiological diagnosis was obtained in 38 (59%) cases. Pneumococcal pneumonia was diagnosed in 32 cases. The statistical analysis showed that the test with best performance was the UA, both in relation to blood and sputum cultures (P<0.05). Two patients died during hospitalization (series mortality of 3%). In conclusion, given its good diagnostic performance, UA should be requested in the ED for the aetiological diagnosis of CAP.

A blood culture is the cornerstone of an established etiological diagnosis of septicemia. Although it is not currently possible to eliminate blood-culture contamination, many interventions have been shown to reduce contamination rates. Retrospective data analysis through an initial audit with major departments at one hospital, including the intensive care unit and emergency department, showed that the blood-culture contamination rate was 4.8%, which is more than the set standard (ie, less than 3%). A decrease in blood-culture contamination rates from the initial 4.8% to less than 3% was obtained with a supervised training and evaluation program through collaborative efforts of the nursing and laboratory departments.

Introduction: Surveillance blood cultures (BCs) are often obtained in hematopoietic stem cell transplant (HSCT) patients for earlier detection of blood stream infections (BSI). The major aim of this study was to determine the utility of the current practice of obtaining surveillance blood cultures from asymptomatic transplant patients upon admission for the preparative regimen., Methods: We conducted an 8-year retrospective study of all patients consecutively admitted to the hospital for a HSCT from 2000 to 2008., Results: In this retrospective analysis, surveillance BCs from 191 eligible patients were analyzed. The incidence of definitive BSIs was 0.52% (1/191) with 6 BCs from other HSCT patients growing probable contaminants. The overall incidence of positive surveillance BCs was 2.9% (7/238) for the BCs taken and 3.7% (7/191) for patients cultured with coagulase negative staphylococcus being isolated from 6 of the 7 patients. The probability of increased BSI after transplantation in patients with initial positive surveillance BCs compared with those having negative BCs, was not significant (P=0.675). No infection-related mortality was observed during the first 60 days posttransplantation in these patients., Conclusions: The frequency of positive surveillance BCs in asymptomatic HSCT patients at the time of hospital admission for transplant seems to be extremely low. These results, if confirmed by larger studies, show the reduced utility of obtaining surveillance BC in asymptomatic patients before administration of the conditioning regimen and the need for re-evaluation of this practice.

Purpose: To evaluate the usefulness of routine blood cultures in patients who develop temperatures of 38.5 degrees C or higher while treated with interleukin-2 (IL-2)., Methods: Retrospective chart review study. Charts of patients treated with high-dose IL-2 or biochemotherapy for metastatic melanoma were reviewed at the University of Louisville from 2005 to 2007. The study objective was to estimate the frequency of true and false positive blood cultures., Results: A total of 205 blood cultures in 46 patients (27 male, 19 female) were reviewed. The average age was 53 years (25-71 years). The patients had an average of 3 cycles of therapy. The mean temperature of the febrile episodes was 38.7 degrees C. The mean absolute neutrophil count was 5.1 K/microL. Of these 205 febrile episodes, only 1 blood culture was true positive. The patient had methicillin sensitive staphylococcus aureus bacteremia. There were 5 false positive blood cultures. Four hundred thirty-four further febrile episodes were documented without blood cultures drawn. None of these patients were found to be infected. The yield of true positive blood cultures in this setting was 0.5% (0%-3%, CI). There was, however, a higher number of false positive blood cultures, 2.4% (0.5%-4.5%, CI)., Conclusions: Blood cultures during IL-2 containing therapy are very inefficient to differentiate between infections versus IL-2-related fever.

Objectives: Although blood cultures are commonly ordered in the emergency department, there is controversy about their utility. This study aimed to determine the usefulness of blood cultures in the management of patients presenting to a tertiary adult teaching hospital emergency department in Perth, Western Australia., Methods: A detailed chart review was undertaken of all blood cultures taken in our emergency department over a 2-month period. All patients within the hospital having blood cultures taken were identified; from this group, blood cultures originating from the emergency department were reviewed. Data were collected concerning patient demographics, culture indication, vital signs, culture outcome, disposition and alterations in management resulting from the blood culture., Results: 218 blood cultures were ordered from the emergency department during the study period. This represented 4.0% (218/5478) of the total number of patients seen. Of the 218 cultures, only 30 were positive (13% of the study population), with 16 (7.3%) probable contaminants and 14 (6.4 %) true positives. No anaerobic isolates were identified. Of the 14 significantly positive blood cultures, the result influenced management in six patients, resulting in a useful culture rate of 2.8% (6/218)., Conclusion: Blood cultures are ordered on a significant number of patients seen in the emergency department but rarely alter management. Our findings in conjunction with other studies suggest that eliminating blood cultures in immunocompetent patients with common illnesses such as urinary tract infection, community acquired pneumonia and cellulitis, may significantly reduce the number of blood cultures, producing substantial savings without jeopardizing patient care. This needs prospective study and validation.

Objectives: To determine the frequency with which clinically significant bacterial pathogens are isolated only from the anaerobic blood culture medium in children evaluated for bacteremia and to describe the clinical features associated with these positive cultures., Methods: Retrospective review of all blood cultures received from the emergency department in the microbiology laboratory. Clinically significant pathogens were defined as microorganisms that rarely are considered to be contaminants or microorganisms that are recovered from multiple blood cultures or sites from the same individual. Charts of all patients with positive anaerobic cultures for clinically significant pathogens in the presence of negative aerobic cultures were reviewed. The setting was an urban tertiary care pediatric emergency department., Results: 2675 paired blood cultures were performed between January 1, 1998 and December 31, 2000. Growth of a bacterial organism occurred in 595 of the paired samples. Two hundred seventy-eight were clinically significant pathogens. One hundred sixty-two (58.3%) were present in both the aerobic and anaerobic mediums, 85 (30.6%) were only in the aerobic medium, and 31 (11.2%) were only in the anaerobic medium. Most patients with growth only in the anaerobic medium had underlying conditions (ie, central venous line, immunocompromised, congenital heart disease, liver disease, age < 3 months). No obligate anaerobic organisms were detected., Conclusions: In a pediatric emergency department setting, almost all pathogenic bacteria were isolated from aerobic culture mediums in otherwise healthy children. The yield of routinely performed anaerobic blood cultures is low. In previously healthy children, it may be optimal to inoculate the entire blood volume obtained into the aerobic medium.

Background: Severe sepsis is frequently associated with inflammation, multiple-organ dysfunction syndrome, and the accumulation of excess fluid that can be removed by continuous renal replacement therapy. Appropriate therapy for sepsis requires knowledge of the antibiotic susceptibility of the causative organism. However, bacterial isolation and identification are often unsuccessful. The objective of this study was to determine whether bacteria could be recovered from continuous renal replacement therapy ultrafiltrates of clinically septic patients who were either blood culture positive or repeatedly culture negative., Design: Clinical study., Setting: Adult medical intensive care unit., Subjects: Six clinically septic, blood culture-positive or repeatedly culture-negative patients and four clinically nonseptic patients., Interventions: We performed continuous renal replacement therapy on patients. In addition, we devised an in vitro system mimicking human bacteremia to determine whether bacteria traverse the hemofilter. In these experiments, a reservoir containing reconstituted blood was inoculated with Enterococcus faecalis and hemofiltered. The ultrafiltrates were centrifuged or secondarily filtered for bacterial recovery., Measurements and Main Results: Bacterial pathogens were recovered in culture from ultrafiltrates of all the clinically septic patients. Ultrafiltrates of the nonseptic patients were sterile. E. faecalis, the bacterium inoculated into the reconstituted blood, was the only organism recovered from the in vitro-derived ultrafiltrates., Conclusions: Pathogenic bacteria were shown to traverse the hemofilter. Culture of ultrafiltrates of clinically septic, blood culture-negative patients may be useful in recovery of the etiological organism and confirmation of the clinical diagnosis and management of sepsis.

Aims: To assess the potential benefit of withdrawing or flushing away the heparin lock before collecting blood for culture from a central venous catheter., Methods: We compared the contamination rates of 152 pairs of blood samples aspirated from central venous catheters in afebrile renal dialysis or cancer patients. We also assessed the antimicrobial effect of 2000 U of heparin in Bactec Plus Aerobic/F culture bottles inoculated with a volunteer's blood plus one of six common bloodstream pathogens., Results: There was no significant difference in contamination rates between first-drawn (26 of 152, 17.1%) and second-drawn (24 of 152, 15.8%) samples. There was no significance difference in yield (58 of 60 [97%] versus 52 of 53 [98%]) or time to flagging positive (16.6 versus 16.7 h) between the bottles with and without heparin., Conclusions: Our results do not support the practice of withdrawing or flushing away the heparin lock before collecting blood for culture from a central venous catheter.

Background: Blood conservation techniques are being increasingly used because of the increased cost and lack of availability of allogeneic blood. Cell salvage offers great blood savings opportunities but is thought to be contraindicated in a number of areas (e.g., blood contaminated with bacteria). Several outcome studies have suggested the safety of this technique in trauma and colorectal surgery, but many practitioners are still hesitant to apply cell salvage in the face of frank bacterial contamination. This study was undertaken to assess the efficacy of bacterial removal when cell salvage was combined with leukocyte depletion filtration., Methods: Expired packed erythrocytes were obtained and inoculated with a fixed amount of a stock bacteria (Escherichia coli American Type Culture Collections [ATCC] 25922, Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus ATCC 29213, or Bacteroides fragilis ATCC 25285) in amounts ranging from 2,000 to 4,000 colony forming units/ml. The blood was processed via a cell salvage machine. The washed blood was then filtered using a leukocyte reduction filter. The results for blood taken during each step of processing were compared using a repeated-measures design., Results: Fifteen units of blood were contaminated with each of the stock bacteria. From the prewash sample to the postfiltration sample, 99.0%, 99.6%, 100%, and 97.6% of E. coli, S. aureus, P. aeruginosa, and B. fragilis were removed, respectively., Discussion: Significant but not complete removal of contaminating bacteria was seen. An increased level of patient safety may be added to cell salvage by including a leukocyte depletion filter when salvaging blood that might be grossly contaminated with bacteria.

Acute hematogenous osteomyelitis (AHOM) of the pelvis is a rare form of childhood osteomyelitis. Prompted by a recent case, we reviewed the 146 reported cases of pelvic AHOM published since 1966. Classical childhood AHOM of tubular bones usually occurs in older children (mean age, 8.1 y) as opposed to younger children (aged 2-5 y). It is more common in boys than in girls (male to female ratio = 1.5:1). The most common site is the ilium (40%), followed by the ischium (28%) and the pubis (15%). In contrast to AHOM of the long bones, trauma is an uncommon antecedent event in pelvic AHOM. The pain in pelvic AHOM may be referred to the hip, thigh, or abdomen, often leading to misdiagnosis. On average, the correct diagnosis is delayed for 12 days. Such delays have resulted in a permanent disability in 3.4% of the cases. If diagnosed and treated promptly, uneventful recovery can be anticipated in all patients. This case history and review of the literature may facilitate early recognition of pelvic AHOM by primary care physicians, as well as by pediatric or orthopedic specialists.

Objective: To investigate alterations in immune responses after transhiatal versus transthoracic esophageal resection and to evaluate the role of preoperative immune functions in predicting postoperative infectious complications., Summary Background Data: Impaired immune defense is associated with a decreased resistance to infection. Patients undergoing esophageal resection via a transhiatal or transthoracic approach are prone to develop infectious complications. There are no randomized data on immune responses after two major surgical interventions., Methods: The study group consisted of 20 patients who were randomly allocated to a limited transhiatal or extended transthoracic esophagectomy for cancer. Blood samples were taken before the operation and at regular intervals thereafter from day 1 to day 10. Monocyte and T-helper type 1 (Th1) and type 2 (Th2) lymphocyte functions were assessed in stimulated whole blood cultures., Results: Both surgical groups had severely depressed in vitro production of interleukin (IL)-12, IL-10, interferon-gamma, IL-2, IL-4, and IL-13 on postoperative day 1. Depression of Th2-type cytokine production was more profound after transthoracic than after transhiatal esophagectomy (IL-4, P=.005; IL-13,P=.007). Postoperative reduction in Th1-type cytokine production was similar between the two groups (interferon-gamma, P=.40; IL-2, P=.06). Irrespective of the surgical approach, patients who developed major infectious complications after surgery presented with a diminished T-cell cytokine production before the operation compared to those who had a relatively uneventful recovery (IL-4, P=.045; interferon-gamma, P=.064). In regression analysis, the occurrence of postoperative major infection was best predicted by increased duration of anesthesia ( P<.0001) and low preoperative interferon-gamma production ( P=.006)., Conclusions: Both transhiatal and transthoracic esophagectomy induced severely depressed monocyte and T-lymphocyte cytokine production. The extent of the surgical procedure had a differential immunosuppressive impact on Th2-type but not on Th1-type cell activity, indicating that the two Th pathways were downregulated through distinct mechanisms. Preoperative interferon-gamma determination would be useful to anticipate the occurrence of postoperative major infectious complications.

Unlabelled: There is little data to support the use of blood culture (BC) testing in the burn patient. Clinical signs (fever, leukocytosis) may not reliably indicate infection; moreover, BC's are expensive, invasive and plagued by false positive results. A policy of critical evaluation of lab utilization was instituted in our burn unit in 1993. By 1997 the use of blood culture testing had decreased by 50%. A retrospective analysis of our change in BC utilization was undertaken to derive practice guidelines for usage of this test., Methods: 47 patients with BC testing in 1997 were compared to a cohort of 47 patients from 1993, representing a total of 441 BC episodes., Results: Comparison of 1993 and 1997 patients revealed no significant differences in patient characteristics or outcomes. The mean white blood cell count and maximum temperature on the day of culture were identical for both positive and negative BC episodes. However, BC's drawn during a state of shock were twice as likely to be positive. Patients who experienced positive BC's had larger burns, received more antibiotics, had more indwelling catheters, and had longer lengths of ventilator support and hospital stays., Conclusions: Higher patient acuity or the presence of indwelling catheters increases the likelihood of a positive BC. Substantial limitation of BC's without observed changes in length of stay, ventilator days, or mortality suggests that this test can be safely limited without compromising patient outcomes.

Aim: It is routine practice to prolong the incubation period of blood cultures from patients with suspected subacute bacterial endocarditis (SBE) or fungal infection. The protocol in this laboratory required 28 days incubation with weekly subcultures. Following the introduction of automated continuously monitored blood culture instruments, the duration of incubation for specimens from these categories of patients was reviewed., Method: In a retrospective study of blood culture specimens submitted from 1 July 1994 to 31 July 1998, the time from collection to a positive signal from the BacT/Alert automated blood culture system, in patients suspected of SBE or fungal infection, was assessed., Results: From 355 patient episodes, 896 bottles were incubated for up to 28 days, during which time 116 bottles (40 patient episodes) signalled positive. Significant organisms from suspected endocarditis patients were isolated from 87 bottles (87%), with the time to detection ranging from 9 to 96 hours. The data collected from significant isolates obtained from clinically suspected fungaemias were extremely small, prompting a review of the total fungal isolates from all blood culture bottles incubated during the study period. Yeast isolates were obtained from 78 (0.08%) bottles with the detection time ranging from 15 to 144 hours., Conclusion: The practice in this laboratory now is to incubate blood cultures for up to 7 days when the clinical notes indicate the possibility of SBE or a fungal infection.

Background: Febrile trauma patients have repeated blood cultures drawn during a prolonged hospitalization. We examined the diagnostic yield of blood cultures in severely injured patients to determine whether concurrent antimicrobial therapy or prophylactic administration of antibiotics affects blood culture growth. We also determined how rapidly growth changed to determine whether total numbers of blood cultures could be decreased. The hypotheses of the study were that concurrent antimicrobial administration affects blood culture yield, prophylactic administration alters the culture result, and repetitive culturing is unnecessary., Methods: A retrospective chart review of trauma patients with minimum Injury Severity Score of 15 and minimum 5-day intensive care unit length of stay was performed. The dates and results of blood cultures and antibiotic type and administration dates were recorded. "Prophylactic" antibiotics were defined as antibiotics administered on admission to the unit. Computer software was used to match the blood culture date to the period of antimicrobial administration. Categorical data were compared using Fisher's exact test., Results: Two hundred fifty-eight patients met entry criteria, and 208 charts were complete for review. One hundred twenty-nine patients had 347 sets of blood cultures drawn. The positive blood culture rate was 10.8% in patients off antibiotics, and 13.9% in patients on antibiotics (p = 0.68). All prophylactic antibiotics included a beta-lactam. Only 18% of positive blood cultures in patients receiving prophylactic antibiotics were sensitive to beta-lactams as opposed to 59% sensitivity in those who did not receive prophylaxis (p = 0.03). One hundred seventy-six sets of blood cultures were performed after an initial positive culture. Only three patients with an initial positive culture had a second positive culture with a different organism. The mean time to culturing a new organism after initial growth was 19 days., Conclusion: Concurrent antimicrobial administration does not alter blood culture yield. Prophylactic administration alters the type of organism cultured. Little new information is gained from repetitive culturing.

Objective: To determine the sensitivity, specificity, and predictive values of cultures done with blood drawn through a central venous or arterial catheter compared with peripheral venipuncture., Design: Retrospective cohort study of critically ill surgical patients in whom samples for paired cultures were drawn through a central venous or arterial catheter and peripheral venipuncture., Setting: Tertiary-care, university-affiliated medical center., Patients: Two hundred seventy-one patients hospitalized on a surgical and a cardiothoracic intensive care unit between November 1994 and August 1997., Interventions: None., Measurements and Main Results: Blinded assessments of culture results done by two physicians were used as the gold standard. Sensitivity, specificity, and positive and negative predictive values were compared for culture of blood from catheters and culture of blood from peripheral venipuncture. Of 499 observations, 426 were catheter-negative/venipuncture-negative, 19 were catheter-positive/venipuncture-positive, 18 were catheter-negative/venipuncture-positive, and 36 were catheter-positive/venipuncture-negative pairs. For catheter draws compared with peripheral venipuncture, sensitivity was 78% (confidence interval [CI], 65% to 90%) and 65% (CI, 50% to 79%) (p = .2), specificity was 95% (CI, 94% to 97%) and 98% (CI, 97% to 99%) (p = .002), positive predictive value was 63% (CI, 51% to 76%) and 78% (CI, 64% to 91%) (p = .1) and negative predictive value was 98% (CI, 96% to 99%) and 97% (CI, 95% to 98%) (p = .3). When central venous specimens as differentiated from arterial catheter specimens were compared with peripheral venipuncture, the difference between positive predictive values reached statistical significance (61% and 82%; p = .04)., Conclusions: In critically ill surgical patients, cultures of blood drawn through a catheter are less specific than those obtained from a peripheral venipuncture. Both types of cultures have an excellent negative predictive value. Positive predictive value of cultures of blood drawn through a catheter is low and, when obtained from a central line, statistically less than from a peripheral venipuncture. Additional cultures seem to be necessary for the proper interpretation of a positive culture drawn through a catheter in critical care patients.

This study sought to determine the yield of blood cultures drawn in the department of emergency medicine. The results of 730 blood cultures taken from 718 patients were retrospectively analysed. The total percentage of positive cultures was 9.7%. Only 3.4% of the blood cultures were classified as true bacteraemia and the rest as contaminants. The commonest type of isolate was coagulase-negative staphylococci (49%), which were considered contaminants in all cases. Other contaminants represented 13.2% of all the positive blood cultures. The following bacteria comprised the group of true bacteraemia: Escherichia coli (12.6%), Streptococcus pneumoniae (9.8%), viridans streptococci (7%), Staphylococcus aureus (2.8%), Bacteroides fragilis (2.8%), Moraxella species (1.4%) and Flavobacterium species (1.4%). Blood cultures were positive in 3.6% of patients with pneumonia and in 10% of patients with urinary tract infections. In patients with fever of unclear source blood cultures were positive in 3.1% of children between 0-36 months of age and in 1.1% of patients older than 16 years. As a whole, patients with positive blood cultures were clinically sicker, a higher percentage of them required admission to the hospital and had higher temperatures or rapidly fatal disease, compared with the group of patients with negative blood cultures. In order to improve the yield of blood cultures in febrile patients, first, better a priori identification of those subjects at high risk for bacteraemia will reduce the number of unnecessary blood cultures and second, sterile venipuncture techniques should be improved in order to reduce the number of contaminants.

Background: In experimental trauma-hemorrhage and sepsis, a sexual dimorphism of cell-mediated immune functions has been described, which has been related to higher susceptibility to and mortality from sepsis in males. Therefore, in the present study, sex differences with regard to cytokine release of endotoxin stimulated whole blood and its relation to the development of severe posttraumatic sepsis were investigated in blunt trauma patients with multiple injuries., Methods: Eighty-four patients (25 female; 59 male) sustaining blunt injuries with an Injury Severity Score > 16 were enrolled in the study. Whole blood and serum were obtained during a 14-day period of hospitalization. The capacity of peripheral blood mononuclear cells to produce cytokines (tumor necrosis factor-alpha, interleukin [IL]-6, IL-8) was tested by using a whole blood assay. Serum samples were assayed for anti-inflammatory cytokines (IL-4, IL-10, and transforming growth factor beta1) and sex hormones (testosterone, estradiol, progesterone). Patients were monitored daily for sepsis criteria according to the ACCP/ SCCM consensus conference 1992., Results: Within the entire patient population, sex differences in posttraumatic cytokine release were not detectable. Male trauma patients developing severe sepsis (n = 16) presented with a significantly increased cytokine producing capacity in the early posttraumatic period (< or = 24 hours after admission to the emergency room) when compared with males with an uncomplicated recovery. In females, differences between the subgroups of patients with (n = 7) and without development of severe sepsis were not detectable. There were no differences in systemic levels of anti-inflammatory cytokines within the early posttraumatic period between the subgroups of male and female patients with and without development of severe sepsis. In females, differences in sex hormone levels were not detectable, whereas in males, development of severe sepsis later was found to coincide with significantly decreased testosterone and increased estradiol serum levels., Conclusion: The present study demonstrates a sex-specific regulation of leukocyte function in patients with multiple injuries within the early posttraumatic period. In male patients with multiple injuries, increased cytokine-producing capacities may correspond to enhanced inflammatory responses, which increase susceptibility to sepsis, whereas in female patients, other regulatory mechanisms may be involved.

Objective: To evaluate the ability of once daily reduced dose clarithromycin to prevent disseminated Mycobacterium avium complex (dMAC) infection in patients with advanced HIV disease., Design: Non-randomized, retrospective study., Setting: Outpatient clinic of an urban university-affiliated municipal hospital., Patients: A group of 192 HIV-infected patients with a CD4 count < 100 x 10(6) cells/l who were followed for at least 90 days during a 6-year period (1991-1996) before the use of protease inhibitors., Interventions: Clarithromycin 500 mg orally once daily (n = 84), rifabutin 300 mg orally once daily (n = 47) or no prophylaxis (n = 61)., Main Outcome Measures: Positive blood culture for M. avium complex (MAC), time to development of dMAC, and time to death., Results: When compared with no prophylaxis or rifabutin, the incidence of dMAC and time to development of dMAC were improved among those patients receiving clarithromycin (P < 0.001). Prolonged survival was associated with both clarithromycin and rifabutin use when compared with no prophylaxis (P < 0.002). In patients who failed prophylaxis, resistance to clarithromycin and rifabutin was observed., Conclusions: In the era prior to protease inhibitor use, once daily clarithromycin at a dose of 500 mg was associated with a reduction in the incidence of dMAC, appeared to be superior to rifabutin, and was associated with prolonged survival in patients with advanced HIV disease.

Objective: To compare silver-coated and uncoated central venous catheters regarding bacterial colonization. To assess the relative contribution of catheter hub and skin colonization to catheter tip colonization., Design: Prospective, randomized clinical trial., Setting: Intensive care unit in a university hospital., Patients: Patients after cardiac surgery who required a central venous double-lumen catheter (DLC)., Interventions: Sixty-seven adult patients were prospectively randomized to receive either a silver-coated (S group, n = 34) or an uncoated control (C group, n = 33) DLC. Blood cultures were drawn at catheter removal, and removed catheters were analyzed with quantitative cultures. Typing of microorganisms included DNA fingerprinting., Measurements and Main Results: Catheters were removed if no longer necessary and aseptically divided into three segments: segment A, the catheter tip; segment B, an intermediate section; and segment C, the subcutaneous portion. Bacterial catheter colonization was quantitatively measured using sonication to detach adherent bacteria from the catheter segments in the broth and subsequent culture of an aliquot. Selected isolates of coagulase-negative staphylococci and other bacteria from catheter segments were examined by means of pulsed-field gel electrophoresis (PFGE) after macrorestriction digestion of bacterial DNA to study colonization pathogenesis. Quantitatively lower bacterial colonization could be demonstrated on the silver-coated catheters (200 +/- 550 colony forming units [CFUs]/cm catheter segment; mean +/- SD). The difference in the control catheters (1120 +/- 5350 CFUs/cm catheter segment; mean +/- SD) was not, however, significant (p = .25). The frequency of colonization of at least one catheter segment was 52.9% for the silver-coated catheters and 57.6% for the control catheters (p= .44), without any significant differences in the colonization of corresponding catheter segments. The rate of significant catheter colonization (i.e., > or = 10(3) CFUs/cm catheter by quantitative catheter culture or > or = 10(3) CFUs/mL by luminal flush) was nine in the silver group and seven in the control group, a difference that failed to reach significance (p = .41). Two patients in both groups developed catheter-related bacteremia. Pattern analysis after PFGE demonstrated that about 70% of the isolates found on the catheter tip were identical with those on the skin at the insertion site, whereas about 75% were identical with those recovered from the hub. In 29% of colonized catheters, identical bacteria were found on the hub and the skin at the insertion site., Conclusions: Silver-coating of DLCs did not significantly reduce bacterial catheter colonization compared with the control catheters. PFGE analysis of coagulase-negative staphylococci and other bacteria demonstrated various pathogenic routes of catheter-related colonization, whereby the microorganisms of the skin flora around the insertion site must be regarded as the main source of catheter-related infections.

The diminution of intraoperative hemorrhage remains a fundamental goal of the burn surgeon. We hypothesized that intraoperative blood salvage during burn excisions would be feasible if predicated on yield, bacteriology, and concentration of inflammatory mediators in the washed product. Reinfusion of culture-positive blood has a clear precedent in the trauma literature. Eight operations with immediate and complete collection of shed blood into a cell-saver device were prospectively studied. A median salvage rate of 43% of total shed red blood cells was estimated to have been recovered. Actual volumetric measurement of intraoperative blood loss was achieved. Bacterial contamination was consonant with the abdominal trauma experience. The levels of C3a, C5a, TNF alpha, and IL-1 beta in the final cell-saver product were all found to be at clinically insignificant levels.

This retrospective study evaluated 15,377 sets of BacT/Alert blood cultures to determine incubation time for blood cultures. Ninety-six per cent (1476) of total isolates signalled positive within five days and 56 isolates turned positive in five to seven days. Of the 56 organisms recovered between five and seven days, 49 were considered contaminants and seven were considered clinically significant. On assessing the medical records of the patients with the seven clinically significant isolates, it was determined that the clinical outcome would not have changed if these isolates were missed. We conclude that a five day incubation protocol reduces the recovery of skin contaminants while not significantly decreasing the recovery of clinically significant organisms. The data suggest that the incubation time can be further reduced but this policy will depend on the individual institution and their patient population mix.

Background: Neutrophils are of great importance for the host's defense against invading organisms. Granulocyte colony-stimulating factor (G-CSF) has been used to augment both the neutrophil number and function, and its prophylactic administration has proved beneficial in animal models of sepsis. However, pretreatment with G-CSF is not practical under clinical conditions. We therefore investigated the effect of recombinant human (rh)G-CSF, administered only after infection, on the survival rate as well as the hemodynamic and cytokine response of the animals., Methods: Chronically catheterized conscious pigs were challenged with Pseudomonas aeruginosa (8 x 10(7) colony-forming units kg(-1) x h(-1) for 120 h (control group, n = 10). Animals in the G-CSF group (n = 7) also received rhG-CSF (5 microg kg(-1) x day(-1)), the first dose being given 3 h after beginning bacterial infusion., Results: The mortality rate was 50% (5/10) and 29% (2/7) in the control and G-CSF groups, respectively (p = NS, control vs. G-CSF group). Fever, severe pulmonary hypertension, and a hyperdynamic response were recorded in all of the animals. In spite of a prompt and significant recovery from the initial leukopenia (p < .05 vs. control group), the animals of the G-CSF group showed no significant differences in the parameters investigated from those of the controls. Compared with the survivors, the interleukin-1 receptor antagonist was markedly elevated in all nonsurvivors after 6 h of sepsis (p < .05)., Conclusions: These data suggest that treatment with rhG-CSF after the onset of bacterial sepsis might not significantly improve the chances of survival for non-neutropenic patients.

Up-regulation of the leukocyte beta 2 integrin, CD18, is a key event in neutrophil-endothelial adhesion and neutrophil-mediated organ injury. Inhibition of CD18 with monoclonal antibodies reduces lung and liver neutrophil sequestration in animal models of Gram-negative bacteremia or endotoxemia. However, with a persistent septic challenge, interference with host leukocyte phagocytic defense could adversely affect outcome. To assess the effects of inhibiting CD18 on organ neutrophil responses, bacteremia, and organ injury after fecal peritonitis, mice underwent cecal ligation and puncture (CLP). At the time of CLP and 12 h later, mice received intravenous anti-CD18 antibody or control IgG. At 3, 6, and 18 h after CLP, lung and liver tissue neutrophil content were measured by myeloperoxidase (MPO) assay, peritoneal cells and blood leukocytes were differentially counted, blood was cultured, and serum aspartate aminotransferase was measured. There was a significant reduction in peritoneal neutrophil migration and an increase in blood neutrophils after anti-CD18 treatment compared with results from treatment with the control antibody. In the anti-CD18-treated group, liver MPO was increased fivefold at 6 and 18 h, while lung MPO was increased two-fold at 18 h when compared with the control antibody-treated group. The anti-CD18-treated group also had an increase in bacteria cultured from the blood at 6 and 18 h and an increase in serum aminotransferase at 18 h. Our data demonstrate that peritoneal neutrophil migration in response to an endogenous fecal challenge is CD18-dependent, and that this mechanism forms a vital part of host defense. Inhibition of CD18 increased neutrophil sequestration in the liver and lung and increased liver injury. This study demonstrates a paradoxical increase in organ neutrophil sequestration using a leukocyte anti-adhesion therapy during sepsis and suggests that anti-adhesion therapies targeted towards neutrophil may worsen outcome if given during an ongoing, localized infection.

Objective: To evaluate the diagnostic yield of blood cultures obtained in a surgical intensive care unit (ICU) and to assess factors potentially influencing yield., Design: Retrospective, descriptive study., Setting: Surgical ICU in a university hospital., Subjects: All patients who had a blood culture obtained during their admission to the trauma/neurosurgical ICU of Presbyterian University Hospital from January 1, 1993 to December 31, 1993., Measurements and Main Results: Blood culture isolates were categorized as pathogens or contaminants and overall diagnostic yield was determined. Blood cultures were positive for pathogens in 4.6% of all culture episodes, while contaminants were isolated in 5.5% of all culture episodes. A total of 23 true bacteremias were identified in 21 patients, for an overall rate of bacteremia of 3.6 per 100 admissions (5.9 per 1,000 patient days). Concurrent antibiotics were being used at the time of blood culture in 65.3% of all culture episodes. The yield for pathogens was significantly lower (2.2%) when cultures were obtained on antibiotics compared with culture episodes obtained off antibiotics (6.4%) (p < .05). Single-set blood culture episodes were obtained in approximately 32% of all culturing episodes with the overall yield for pathogens of these culturing episodes lower (2.9%) than that of multiple-set culture episodes (5.3%) (p = NS)., Conclusions: Blood culture yield in this surgical ICU was relatively low in comparison with other published studies. The data further suggest that concurrent use of systemic antibiotics and inappropriate or excessive culturing may negatively influence blood culture yield.

Objectives: Dimorphic Candida albicans spp. increasingly cause lethal septic shock and disseminated infection in the critically ill. Following candidemia, production of specific fungal exotoxins coincident with the yeast to hyphal phenotypic transition is believed to be important in the pathogenesis of Candida septic shock. However, overexpression of the pleiotropic cytokine tumor necrosis factor (TNF)-alpha by the host following hyphal germination is also thought to be a mechanism of Candida-related cardiopulmonary dysfunction, as well as of bacteremic shock. In this study, we hypothesized that increases in circulating TNF-alpha coinciding with the yeast to hyphal transition modulate the onset and progression of shock with multiple organ injury early after hematogenous candidiasis., Design: Prospective, controlled laboratory animal study., Setting: University hospital animal research facility., Subjects: Pathogen-free, male Sprague-Dawley rats (n = 26)., Interventions: Conscious, antibiotic-treated animals with chronic indwelling carotid arterial and jugular venous catheters were intravenously infected with 10(9) viable blastoconidia of the C. albicans clinical pathogen, CA-MEN (n = 10), over 30 mins and ending at t = 0 hr, compared with an equivalent inoculum of its viable agerminative mutant, CA-MM2002 n = 11), or an intravenous infusion of 0.9% sodium chloride (n = 5)., Measurements and Main Results: Mean arterial pressure (MAP), pulse rate, respiratory frequency, rectal temperature, acid-base status, quantitative blood cultures, circulating alanine aminotransferase (ALT), and bioactive TNF-alpha were serially measured in all three groups over 24 hrs or until death. Organ cultures, wet/dry weight ratios, and histopathologic changes in the lungs, heart, liver, and kidneys were determined in Candida-infected and 0.9% sodium chloride (normal saline)-infused subgroups at 6 and 24 hrs. Animals hematogenously infected with the C. albicans clinical isolate developed lethal nonendotoxemic shock in < or = 6 hrs (MAP 49 +/- 7 mm Hg [SEM]; p < .05 vs. t = 0 hr), and at death (7.0 +/- 0.3 hrs) were acidotic, hypocapnic, and hypothermic (rectal temperature 33.2 +/- 0.7 degrees C). Despite similar peak concentrations of circulating fungal colony-forming units (cfu) and kinetics of vascular clearance in both Candida-infected groups, survival and MAP in rats challenged with the agerminative C. albicans mutant were unchanged for > 8 hrs, as were pH, Pco2, and rectal temperature. No germination of the agerminative fungal strain occurred in vivo over 6 hrs. Serum TNF was nearly undetectable at t = 0 hr in all three groups. Although shock developed soon after fungemia with the C. albicans clinical isolate, TNF-alpha concentrations did not increase above normal saline values in either candidemic group at t = 1.5, 4.5, or 6 hrs (17 +/- 7 vs. 14 +/- 1 U/mL in the parent C. albicans organism vs. its agerminative mutant at t = 6 hrs). Greater numbers of agerminative C. albicans than its dimorphic parent strain were recovered from the lungs (5.41 +/- 1.0 vs. 2.02 +/- 0.38 x 10(7) cfu/g, respectively; p < .05) and kidneys (p < .01). By 24 hrs, modest germination of the mutant Candida strain was observed in the tissues. However, lung wet/dry ratios, intrapulmonary hyphal proliferation, and alveolar hemorrhage were all greater after infection with the parent fungal isolate. Likewise, myocardial necrosis and hepatic glycogen depletion with vacuolization were more severe after infection with the C. albicans clinical isolate vs. candidemia with its agerminative mutant, although serum ALT values did not differ between these groups., Conclusions: Lethal C. albicans sepsis with lung injury and multiple organ damage are temporally associated with the in vivo yeast to hyphal transition in this model. However, this candidemic septic shock syndrome is modulated by circulating fungal virulence factors or host mediators other than TNF-alpha, a cytokine considered essen

Objective: To assess the relevance, both clinical and bacteriologic, of the use of resin-containing blood culture media in blood cultures taken from critically ill patients receiving antibiotics., Design: A prospective, open clinical trial., Setting: The mixed medical surgical intensive care unit (ICU) of a 550-bed urban hospital., Patients: All ICU patients admitted during a 3-month period (n = 49) with suspected sepsis requiring blood cultures as part of their laboratory investigations., Interventions: The use of an aerobic resin-containing blood culture medium, in addition to the regular aerobic and anaerobic media for all blood cultures taken., Measurements and Main Results: Each blood culture result was classified as to its clinical significance. Changes in patient management were recorded. Culture sets in which the resin-containing bottle provided the information central to the change in patient management were identified. Bacteriologically, the results from the resin-containing medium were compared with the results from the aerobic and anaerobic media. Of 266 blood culture sets, 103 (39%) were positive, growing 278 bacterial and fungal isolates. Clinically, the resin-containing medium alone provided relevant data leading to changes in patient management on three occasions. On two of these occasions, cultures from the regular media provided the same data within 72 hrs. Bacteriologically, 77 (29%) aerobic bottles, 55 (21%) anaerobic bottles, and 89 (33%) resin-containing bottles were positive (statistical comparison of percentages: aerobic vs. resin-containing bottles, nonsignificant; aerobic vs anaerobic bottles, p < .046; anaerobic vs. resin-containing bottles, p < .0027). A similar proportion of pathogens was isolated from the resin-containing bottles only (9%) and aerobic bottles only (6%). A higher proportion of contaminants was isolated from the resin-containing bottles only than the aerobic bottles only in the various sets (17% vs. 7%, p < .046). The resin-containing bottle showed a trend toward increased detection of Staphylococcus aureus and Pseudomonas aeruginosa bacteremia., Conclusions: The resin-containing medium offers little clinical benefit to the majority of ICU patients. Bacteriologically, it seems to have a similar overall sensitivity as the regular aerobic medium (with the possible exception of a higher sensitivity for the isolation of S. aureus and P. aeruginosa), but a lower specificity. The wide-spread use of the resin-containing bottle cannot be recommended.

Objective: Reporting and evaluating a general pediatric unit experience with a simplified protocol based on clinical signs stated on admission used to classify cases of periorbital cellulitis in potential high- and low-risk complication groups., Population: All children under the age of 14 years with acute periorbital swelling not resulting from an immediate direct trauma to the eye and the orbit, referred to the emergency department between December 1, 1986, and December 31, 1992., Method: A high-risk case was defined by: age under two months, meningeal or focal neurologic signs, vision loss, limitation of eye movement, eye malformation or operation in the vicinity, and clinically toxic child on admission. Absence of these elements defined the low-risk case. Initial antibiotic management was the same in both groups, but work-up was different according to the classification of the case., Results: Thirty-four patients were included in the study. Only one (six months old) had a positive blood culture with Haemophilus influenzae found in the low-risk group (16 patients), and no serious complication was encountered. In the high-risk group (18 patients), five had positive cerebrospinal fluid and/or blood culture, two had subperiosteal abscesses, and three had intracranial abscesses. In the whole series, "toxicity" was significantly associated with either positive cerebrospinal fluid or blood culture. Fifty percent of positive cultures were due to H. influenzae., Conclusion: The protocol is considered practical, safe, and represents a suitable triage tool particularly if the high-risk age was raised to 12 months. There is no necessity to perform lumbar puncture in the low-risk group.

Bacterial translocation across the gut wall may be associated with insult to the latter. In this situation, intestinal flora can enter the blood stream and lymph nodes and be transported to other organs. Glutamine is a nonessential amino acid not presently included in total parenteral nutrition (TPN) preparations. The use of glutamine-enriched TPN in the rat has resulted in a significant reduction in bacterial translocation. This study attempted to evaluate the role of glutamine in preventing bacterial translocation following hemorrhagic shock in a rat model. Forty Sprague-Dawley rats were equally divided into two groups. The controls were given TPN solution, while the treated group had glutamine instead of the standard alanine present in TPN. Hemorrhagic shock was induced in both groups and blood cultures were performed. Glutamine-treated rats did not show a significant difference in survival suggesting that it is of no particular value in severe hemorrhagic shock in rats.

This study investigated the effects of incubation delay on the rate of recovery of common pediatric pathogens from blood culture bottles. Known concentrations of Streptococcus pneumoniae and Haemophilus influenzae type b (three isolates each) were inoculated into BACTEC NR-6A bottles with 1.0 mL of donor blood. Bottles were subjected to a time delay (zero to six hours) before incubation. The BACTEC NR-660 was used for incubation and measurement of positive conversion. Data were analyzed using chi 2 analysis, Fisher's exact test, logistic regression, and multiple logistic regression, with P < 0.05 considered significant. Immediate incubation yielded positive blood cultures in 88 of 100 and 65 of 70 bottles containing S. pneumoniae and H. influenzae type b, respectively, in the concentration range 1.0 to 9.99 colony-forming units per milliliter (CFU/ml). For each organism, this was the minimal range required to produce a positive culture (P < 0.0001). Bottles inoculated with 1 ml of blood containing organisms in the range of 1.0 to 9.99 CFU/ml were then subjected to incubation delay. The recovery rate of S. pneumoniae significantly (P = 0.0003) decreased from a two-hour delay (57 of 60; 95%) to a three-hour delay (42 of 60; 70%). No significant change in recovery rate was seen in bottles inoculated with H. influenzae type b subjected to similar delays. Delayed incubation (two to six hours) of bottles inoculated with 1.0 ml of blood containing organisms in a concentration range of 1.0 to 9.99 CFU/ml of blood significantly decreases the recovery rate of S. pneumoniae but has no effect on H. influenzae type b.