Independent Risk Factors For Bacteremia Research Articles

Pre‐engraftment bacteremia after allogeneic hematopoietic cell transplantation without primary fluoroquinolone antibacterial prophylaxis

AbstractBackgroundBacteremia is a common complication in allogeneic hematopoietic cell transplant recipients (alloHCTr), especially during the pre‐engraftment period. International guidelines recommend antibacterial prophylaxis (ABP), despite potential selection for multidrug‐resistant organisms (MDRO). Limited contemporary data exist on the epidemiology of pre‐engraftment bacteremia in alloHCTr, who do not receive ABP.MethodsWe performed a retrospective observational single‐center cohort study including all consecutive adult alloHCTr (2015–2021), investigating the incidence, risk factors, and outcomes of bacteremia during the engraftment period. Primary fluoroquinolone (FQ) ABP is not routinely administered in our center.ResultsAmong 421 patients identified, 124 bacteremia episodes were observed in 121/421 (29%) alloHCTr. The median time to the 1st bacteremia episode was 9 days (IQR 6–11). Most (105/124, 85%) episodes were monomicrobial, while >1 pathogens were identified in 19/124 (15%) episodes. Overall, 152 pathogens were isolated, with a predominance of Gram‐positive (118/152, 78%), including coagulase‐negative staphylococci (n:47), streptococci (n:46), and enterococci (n:15), followed by Gram‐negative bacteria (GNB, 30/152, 20%), and anaerobes (4/152, 3%). There were 2/152 (1%) MDRO (extended‐spectrum beta‐lactamase producing) GNB. Multivariable analyses identified age >40‐year‐old (OR 2.4, P = 0.02), male gender (OR 1.8, P = 0.02), and a haploidentical/mismatched unrelated donor (OR 2.5, P < 0.001) as independent risk factors for bacteremia. All cause 30‐day mortality among alloHCTr with bacteremia was 0.8% (1/121): one patient died due to an HCT‐related complication.ConclusionDespite lack of primary FQ ABP, low rates of bacteremia were observed during the pre‐engraftment period, with low MDRO prevalence and mortality. Our findings may allow to revisit the need for primary universal FQ ABP in high‐risk neutropenic hematology patients. image

Risk factors associated with bacteremia in burn children admitted to a specialized pediatric intensive care unit: A case-control study.

Infections due to bacteremia in burn patients are a common cause of complications and an extended length of stay. Knowing causative microorganisms and identifying associated risk factors allow to reduce infectious complications, morbidity, mortality, and health care expenditure. This study assesses the extent of the association between risk factors and bacteremia in burn patients and identifies the most common microorganisms found in blood cultures. Case-control study conducted at the Burn Intensive Care Unit of Hospital de Pediatría S.A.M.I.C. "Prof. Dr. Juan P. Garrahan" between June 1st, 2014 and September 30th, 2019 in patients with bacteremia events and a positive blood culture (cases) and patients with a negative blood culture (controls). During the study period, 29 cases of bacteremia were identified. The median length of stay at the time of bacteremia was 23 days. The most commonly identified microorganism was Pseudomonas (7 cases). The only risk factor that showed a significant association was the presence of a central venous line for 7 days or more (OR: 3.18; 95 % confidence interval: 1.20- 8.38). The overall mortality rate was 9.1%; 13.8% for cases and 3.4% for controls. Central venous lines for more than 7 days are an independent risk factor for bacteremia in critically ill burn children. No statistically significant association was established with other studied risk factors. Pseudomonas, Acinetobacter, and coagulase-negative Staphylococcus were the most common microorganisms found in bacteremia.

Evolution of Acinetobacter baumannii in Clinical Bacteremia Patients.

IntroductionColonization of the respiratory tract by Acinetobacter baumannii has been established as an independent risk factor for bacteremia. However, within-host evolution of A. baumannii in bacteremia has not been extensively investigated.MethodsWe performed whole-genome sequencing to discover the evolutionary characteristics that accompany the transition from respiratory tract carriage to bloodstream infection in three patients with A. baumannii bacteremia.ResultsWithin-host genetic diversity was identified. A total of 21 single nucleotide variants (SNVs) were detected. Genic and intergenic evolution occurred particularly in secretion system, DNA recombination, and cell motility genes. Intergenic SNVs occurred more frequently compared to synonymous and non-synonymous SNVs, which indicated potential transcription or translation regulation. Non-synonymous mutations mostly occurred during the transition from respiratory tract carriage to bloodstream infection. Isolates of clonal complex 208 (CC208) had lower substitution rate with approximately 10−6 nucleotide substitutions per site year−1, compared with non-CC208 isolates (approximately 10−5). We found evidence for the occurrence of recombination in one patient. A total of 259 genes were found to be gained or lost during the within-host evolution, and 231 genes were only detected in one patient. Gene function annotation results suggested that most genes (71/259) were related to replication, recombination, and repair. Universal bloodstream specific genes were not found in all three patients, and only one putative membrane protein related gene was lost in two patients.ConclusionOur results indicated that within-host evolution of A. baumannii bacteremia was driven by mutations, gene content changes, and limited effect of recombination. Gene content diversity between different patients was identified, which suggested interplay of both host and pathogen factors in within-host genetic diversity. Secretion system-related genes showed higher frequency of genomic variations during the within-host evolution. Our findings enhanced our understanding of within-host evolution of A. baumannii bacteremia and provided a framework for discovering novel genomic changes and pathogenicity genes important for bacteremia, which will be validated in future studies.

1678. Evaluation of Sodium-Glucose Co-Transporter 2 Inhibitor Therapy and Other Potential Risk Factors for the Development of Bacteremia in Patients with Urosepsis

BackgroundThough sodium-glucose co-transporter 2 (SGLT2) inhibitors have been associated with an increased risk of urinary tract infection, it is unknown whether SGLT2 inhibitors increase the risk of urinary-source bacteremia. Early recognition of bacteremia risk factors in patients with urosepsis could allow rapid management to improve patient outcomes. The purpose of this study is to assess patients presenting with urosepsis and a positive urine culture to evaluate the impact of sodium-glucose co-transporter 2 (SGLT2) inhibitor receipt and other potential risk factors for developing bacteremia.MethodsThis was a single-center, retrospective, case-control study performed at a community hospital. Patients were included if they presented with a positive urine culture and met pre-specified criteria for urosepsis. Patients were categorized in one of two groups: bacteremia and non-bacteremia. The following patients were excluded: confirmed pregnancy, age less than 18 years, and/or a proven source of bacteremia outside the urogenital tract. The primary endpoint assessed the percentage of patients taking a SGLT2 inhibitor in the bacteremia versus non-bacteremia groups. Independent risk factors for bacteremia were assessed via binary logistic regression. Additional statistical analysis included chi-square for categorical data and Student’s t-test for continuous data.ResultsA total of 162 patients were analyzed in the study (n=81 in bacteremia and non-bacteremia groups). There was no difference in percentage of patients with or without bacteremia who received SGLT2 inhibitor therapy (p = 0.499). The following were identified as independent risk factors for bacteremia in the binary logistic regression analysis: temperature ≥ 100.4 degrees Fahrenheit (OR 4.1; 95% CI 1.5 – 11.4), bicarbonate level < 20 mmol/L (OR 11.4; 95% CI 3.1 – 41.5), and blood glucose level > 180 mg/dL (OR 3.9; 95% CI 1.3 – 11.6).ConclusionIn this study of patients in a community hospital, SGLT2 inhibitors in the setting of patients with urosepsis and positive urine cultures did not increase the risk for bacteremia. Independent risk factors associated with an increased risk of bacteremia included temperature ≥ 100.4 degrees Fahrenheit, bicarbonate level < 20 mmol/L, and blood glucose level > 180 mg/dL.Disclosures All Authors: No reported disclosures

The neutrophil-to-lymphocyte ratio is associated with bacteremia in older adults visiting the emergency department with urinary tract infections.

We evaluated the clinical features of older adults visiting the emergency department (ED) with urinary tract infections (UTIs), and the diagnostic utility of the neutrophil-to-lymphocyte ratio (NLR) in terms of identifying bacteremia. In total, 479 older adults admitted with UTIs via the ED between January 2010 and December 2015 were retrospectively reviewed. We recorded age, sex, comorbidities, body temperature, clinical findings, and initial laboratory results, including the NLR. A UTI with bacteremia was identified in 186 (38.8%) older adults. Bacteremia was associated with a longer hospital stay (median 10 vs. 8days, p < 0.001). NLRs and C-reactive protein, blood urea nitrogen and creatinine levels were significantly higher in the bacteremia group than in the non-bacteremia group (p < 0.001, p = 0.016, p = 0.008, and p = 0.011, respectively). The area under the curve for the NLR was 0.624 (95% CI = 0.579-0.668, p < 0.001), and the cutoff was 9.0 (sensitivity 74.2, specificity 49.2%). Independent risk factors for bacteremia were an NLR ≥ 9 and fever ≥ 39°C (OR 2.43, OR 2.75: p < 0.001, p < 0.001, respectively). Bacteremia was associated with a longer hospital stay in older adults with UTIs, in whom the initial NLR and high fever reliably predicted bacteremia. The NLR may help emergency physicians to predict bacteremia in older adults with UTIs visiting the ED.

Can excretory phase computed tomography predict bacteremia in obstructive calculous pyelonephritis?

Acute pyelonephritis (AP), a complication of urolithiasis, can be fatal if it progresses to septic shock. We aimed to evaluate the performance of excretory phase computed tomography (CT) in predicting bacteremia among AP patients with upper urinary tract calculi. We reviewed medical records of 250 patients diagnosed with AP and upper urinary tract calculi and who were admitted to our institute. We analyzed 132 patients who underwent excretory phase CT. Excretory phase CT images were obtained 7min after injection with the contrast agent. Obstruction was classified either as high or low grade. Univariate and multivariate analyses were performed to identify the risk factors of bacteremia. Of 132 patients, 73 (55.3%) had bacteremia. Escherichia coli was the most frequently identified pathogen in blood cultures. Univariate analysis demonstrated that high-grade obstruction on excretory phase CT and quick Sepsis-related Organ Failure Assessment (qSOFA) score ≥ 2 were correlated with bacteremia. In addition, the administration of vasopressors was significantly associated with bacteremia (31.5% vs. 6.8%; p < 0.001). Multivariate analysis identified high-grade obstruction on excretory phase CT [odds ratio (OR) 6.68; p < 0.001] and qSOFA score ≥ 2 (OR 3.59, p = 0.03) as independent risk factors for bacteremia. Excretory phase CT images can be used to predict bacteremia by evaluating the degree of ureteral obstruction. The evaluation of the passage of urine shown by excretory phase CT is critical in patients with AP associated with upper urinary tract calculi.

Impact of Enteral Nutrition with an Immunomodulating Diet Enriched with Hydrolyzed Whey Peptide on Infection After Liver Transplantation.

Infection is a leading cause of death after liver transplantation (LT). Therefore, prevention of infection is crucial for improving outcomes after LT. We examined the impact of early enteral nutrition with an immunomodulating diet (IMD) enriched with hydrolyzed whey peptide (HWP) formulation on infection after living donor LT (LDLT), focusing on sarcopenia. This study enrolled 279 consecutive patients who underwent primary LDLT at our institute between January 2008 and April 2015. Early enteral nutrition with the IMD enriched with HWP formulation and a conventional elemental diet were started within the first 24h after surgery for 164 (IMD-HWP) and 115 (conventional) patients. Sequential changes in nutritional parameters, and the incidences of acute cellular rejection (ACR) and bacteremia were compared between the IMD-HWP and control groups. The comparison was made between those members of each group that did or did not exhibit sarcopenia. Risk factors for post-transplant bacteremia were also assessed. Postoperative nutritional parameters and the incidence of ACR were comparable between the groups, except for the prealbumin level. The incidence of bacteremia was significantly lower in the IMD-HWP group, and among patients without sarcopenia in the IMD-HWP group compared with the conventional group (24.4 vs. 41.7%; P = 0.002 and 20.8 vs. 39.0%; P = 0.040, respectively). Independent risk factor for bacteremia comprised bleeding ≥10,000mL (P = 0.025). In contrast, enteral nutrition without HWP formulation was not significantly associated with bacteremia. However, enteral nutrition without HWP formulation (P = 0.080), MELD scores (P = 0.097), and ABO incompatibility (P = 0.088) showed a trend toward increased incidence of bacteremia, although they did not reach statistical significance in the multivariate analysis. Postoperative immunonutrition with an IMD enriched with HWP formulation was closely involved with post-transplant bacteremia.

Bacteremic vs nonbacteremic urinary tract infection in children

AimBacteremia is an uncommon complication of urinary tract infection (UTI). The aim of this study was to identify risk factors for bacteremic UTI in pediatric patients. MethodsThe medical records of all pediatric patients with UTI between 2013 and 2014 were retrospectively reviewed. Pediatric patients with accompanying bacteremia were compared with pediatric patients with no bacteremia. ResultsFive hundred twenty-seven cases of UTI were identified. Blood cultures were taken in 464, 26 (5.6%) of which also were bacteremic. Pediatric patients with bacteremia were more likely to be male (58% vs 28%, P<.01), to be younger than 3 months (54% vs 31%, P=.02), and to have higher creatinine (average 0.77±0.97 vs 0.34±0.24, P<.01). Pediatric patients with bacteremia had higher rate of underlying urologic conditions. The following variables were included in multivariate analysis: age <3months, sex, ethnicity, method of urine collection, creatinine, and underlying urologic conditions. Only creatinine (odds ratio, 3.67; 95% confidence interval, 1.69-8.11) was found as an independent risk factor for bacteremia. ConclusionsHigh creatinine at presentation is a risk factor that might aid in early identification of pediatric patients with high risk for bacteremia and its complications.

Febrile urinary tract infection in the emergency room.

To review the recent advances in the diagnostic and therapeutic approach to adults presenting with febrile urinary tract infection (UTI) in the emergency department (ED). Recent research suggests overdiagnosis and therefore overtreatment of UTI in the ED, especially in the elderly. Antimicrobial pretreatment, an indwelling catheter, and malignancy are independent risk factors for bacteremia with uropathogens that cannot be cultured from urine. A simple clinical prediction rule can predict clinically relevant radiologic findings in patients with invasive UTI. Procalcitonin is a marker for bacteremia; pro-adrenomedullin predicts a complicated course and 30-day mortality in complicated UTI. Several reports have identified the risk factors for resistant uropathogens in community-acquired febrile UTI. Adherence to the guidelines and early culture-guided intravenous-to-oral switch reduces the length of hospitalization. An effective strategy is needed to improve the diagnosis of UTIs in acute care. Further research regarding biomarker-guided triage might improve the management of patients with febrile UTI. Future efforts should be directed toward the improvement of adherence to UTI treatment guidelines.

Molecular epidemiological characteristics of Klebsiella pneumoniae associated with bacteremia among patients with pneumonia.

Some important virulence factors have been elucidated in Klebsiella pneumoniae infections. We investigated the relationship between virulence factors and multilocus sequence types (STs) and assessed the risk factors for bacteremia in patients with pneumonia due to K. pneumoniae. From April 2004 through April 2012, a total of 120 K. pneumoniae isolates from patients with pneumonia (23 with bacteremia and 97 without bacteremia) were collected from 10 medical institutions in Japan. Additionally, 10 strains of K. pneumoniae serotype K2 that were isolated >30 years ago were included in this study. These isolates were characterized using multilocus sequence typing (MLST), and the characteristics of their virulence factors, such as hypermucoviscosity phenotype and RmpA and aerobactin production between patients with and without bacteremia, were examined. MLST analysis was performed on the 120 isolates from patients with pneumonia, and some sequence type groups were defined as genetic lineages (GLs). GL65 was more prevalent among patients with bacteremia (21.7%) than in those without bacteremia (7.2%). The majority of the strains with serotype K2 were classified into GL14 or GL65, and rmpA and the gene for aerobactin were present in all GL65-K2 strains but absent in all GL14-K2 strains. In a multivariate analysis, the independent risk factors for bacteremia included GL65 (adjusted odds ratio [AOR], 9.46; 95% confidence interval [CI], 1.81 to 49.31), as well as neoplastic disease (AOR, 9.94; 95% CI, 2.61 to 37.92), immunosuppression (AOR, 17.85; 95% CI, 1.49 to 214.17), and hypoalbuminemia (AOR, 4.76; 95% CI, 1.29 to 17.61). GL65 was more prevalent among patients with bacteremia and was associated with the virulence factors of K. pneumoniae.

Predictors of Bacteremia Among Children With Sickle Cell Disease Presenting With Fever

Bacterial sepsis is more common and potentially life threatening in children with sickle cell disease (SCD). Identification of variables that predict bacteremia may aid clinicians in recognizing patients with SCD at higher risk for sepsis. To determine whether absolute neutrophil count (ANC) >20×10/L is an independent risk factor for bacteremia in children with SCD and to identify other predictors of bacteremia in this population. A case-control study was conducted. Subjects were 0 to 18 years of age admitted to a tertiary care pediatric hospital over a 17-year period with SCD and fever at presentation. Cases had bacteremia, whereas controls had negative blood cultures. Data were analyzed for 40 cases and 120 controls. ANC>20×10/L was significantly more prevalent among cases (odds ratio [OR], 7.0; 95% confidence interval [CI], 2.6-18.9). Cases were more likely to have emesis (OR, 2.9; 95% CI, 1.0-8.4) and a higher proportion of band cells (OR, 1.3; 95% CI, 1.1-1.4) at presentation. In a febrile child with SCD, an ANC>20×10/L, a higher proportion of band cells, and the presence of vomiting were associated with an increased likelihood of bacteremia.

Evaluation of risk factors for vancomycin‐resistant Enterococcus bacteremia among previously colonized hematopoietic stem cell transplant patients

Hematopoietic stem cell transplantation (HSCT) recipients colonized with vancomycin-resistant Enterococcus (VRE) may have an increased risk of developing VRE bacteremia. Identification of risk factors for the development of subsequent VRE bacteremia among colonized HSCT recipients is necessary to predict which patients may benefit the most from receiving anti-VRE antibiotic therapy as part of an initial antimicrobial regimen when gram-positive bacteremia is suspected. This study was a retrospective chart review conducted from May 2008 to May 2011. Adult HSCT patients admitted to the hospital found to have positive VRE surveillance cultures were included. A multivariate analysis was completed to identify risk factors for the development of VRE bacteremia in the study population. Of 152 patients, 19 (13%) patients developed subsequent VRE bacteremia. Risk factors identified for patients with current VRE colonization for VRE bacteremia were the utilization of vancomycin subsequent to VRE surveillance culture positivity (P=0.017), prolonged duration of neutropenia (P=0.001), immunosuppression (P<0.001), and timing of first VRE surveillance screen positivity at week 1 (P=0.005). A history of VRE colonization on a prior admission was not an independent risk factor for bacteremia in HSCT patients (P=1.0). HSCT patients with VRE bacteremia had a 30-day all-cause inpatient mortality rate of 29% (P=0.001). HSCT patients receiving immunosuppressive therapy, who have been exposed to vancomycin subsequent to surveillance culture positivity, have had prolonged neutropenia of >30days, or first surveillance culture positive at week 1 of admission are potential candidates for early implementation of anti-VRE therapy when a gram-positive bacteremia is suspected.

Risk factors for bacteremia due to extended-spectrum beta-lactamase-producing Escherichia coli in a Turkish hospital

Bloodstream infection caused by extended-spectrum beta-lactamase (ESBL)-producing pathogens has become a serious concern worldwide. The purpose of this study was to identify risk factors for bacteremia due to ESBL-producing Escherichia coli in a Turkish hospital. We retrospectively reviewed the medical records of patients with E. coli bacteremia in a tertiary care centre from January 2007 to October 2011. Data from patients such as demographic features, underlying conditions, and antibiotic exposure were analysed. A total of 113 patients with bacteremia due to E. coli were included and data from patients with ESBL-producing E. coli (case patients) were compared to those with non-ESBL-producing E. coli (control patients). The frequency of ESBL producers was 38.9% (44/113). Exposure to fluoroquinolones and cephalosporins, history of intra-abdominal surgery intervention, and presence of central venous catheteter and urinary catheteter were more frequently detected among case patients (P < 0.05). Independent risk factors for bacteremia due to ESBL-producing E. coli were exposure to fluoroquinolones (OR 13.39, 95% CI 1.28-140.03) and cephalosporins (OR 3.48, 95% CI 1.03-11.74). Previous use of fluoroquinolone and cephalosporin in patients with bacteremia caused by E. coli increased the risk for ESBL-producing strains.

Beneficial effects of supplementation with branched-chain amino acids on postoperative bacteremia in living donor liver transplant recipients

The aim of this study was to investigate the effects of preoperative oral supplementation with branched-chain amino acids (BCAAs) on postoperative bacteremia after living donor liver transplantation (LDLT) for chronic liver failure. Two hundred thirty-six patients who underwent adult-to-adult LDLT were evaluated in this retrospective study. The patients were divided into 2 groups: those who received oral supplementation with BCAAs before transplantation (the BCAA group; n = 129) and those who did not (the non-BCAA group; n = 107). Before the LDLT indication was determined, BCAA supplementation was prescribed by a hepatologist to preserve hepatic reserves. The clinical characteristics and the incidence of bacteremia were compared between the 2 groups. As for clinical characteristics, the Child-Pugh scores (P = 0.0003) and the Model for End-Stage Liver Disease scores (P = 0.0008) were significantly higher in the BCAA group versus the non-BCAA group. The incidence of bacteremia for Child-Pugh class C patients was significantly lower in the BCAA group (6/90 or 6.7%) versus the non-BCAA group (11/50 or 22.0%, P = 0.0132). In a multivariate analysis, non-BCAA supplementation was an independent risk factor for bacteremia. In conclusion, preoperative BCAA supplementation might reduce the incidence of bacteremia after LDLT. Nevertheless, this is a preliminary report, and further studies, such as randomized, prospective studies, are necessary to clarify the beneficial effects of BCAA supplementation on postoperative bacteremia after liver transplantation.

Predicting Bacteremia among Patients Hospitalized for Skin and Skin-Structure Infections: Derivation and Validation of a Risk Score

Bacteremia is relatively common in patients with skin and skin-structure infection (SSSI) severe enough to require hospitalization. We used selected demographic and clinical characteristics easily assessable at initial evaluation to develop a model for the early identification of patients with SSSI who are at higher risk for bacteremia. A large database of adults hospitalized with SSSI at 97 hospitals in the United States during the period from 2003 through 2007 and from whom blood samples were obtained for culture at admission. We compared selected candidate predictor variables for patients shown to have bacteremia and patients with no demonstrated bacteremia. Using stepwise logistic regression to identify independent risk factors for bacteremia, we derived a model by using 75% of a randomly split cohort, converted the model coefficients into a risk score system, and then we validated it by using the remaining 25% of the cohort. Bacteremia was documented in 1,021 (11.7%) of the 8,747 eligible patients. Independent predictors of bacteremia (P<.001) were infected device or prosthesis, respiratory rate less than 10 or more than 29 breaths per minute, pulse rate less than 49 or more than 125 beats per minute, temperature less than 35.6 degrees C or at least 38.0 degrees C, white blood cell band percentage of 7% or more, white blood cell count greater than 11x10(9)/L, healthcare-associated infection, male sex, and older age. The bacteremia rates ranged from 3.7% (lowest decile) to 30.6% (highest decile) (P<.001). The model C statistic was 0.71; the Hosmer-Lemeshow test P value was .36, indicating excellent model calibration. Using data available at hospital admission, we developed a risk score that differentiated SSSI patients at low risk for bacteremia from patients at high risk. This score may help clinicians identify patients who require more intensive monitoring or antimicrobial regimens appropriate for treating bacteremia.

Risk Factors for Bacteremia with Uropathogen Not Cultured from Urine in Adults with Febrile Urinary Tract Infection

In a prospective study involving 642 patients with febrile urinary tract infection (UTI), we found antimicrobial pretreatment (odds ratio [OR], 3.3), an indwelling urinary catheter (OR, 2.8), and malignancy (OR, 2.7) to be independent risk factors for bacteremia with a uropathogen that was not cultured or recognized in the urine. Although the diagnostic value of blood cultures has been questioned in UTI, we advocate performing blood cultures for patients with these risk factors.

Multidrug resistant gram‐negative bacilli as predominant bacteremic pathogens in liver transplant recipients

Bacteremias, which are often caused by gram-negative bacteria, are the most frequently occurring infectious complications after liver transplantation (LT). The aim of this study was to investigate bacteremic incidence, pathogenic spectrum, risk factors for bacteremia due to multidrug resistant (MDR) gram-negative bacilli, and its impact on mortality after LT. A cohort analysis of prospectively recorded data was done in 475 LT recipients, who were divided into 3 categories: cases with gram-negative bacteremia, cases with MDR gram-negative bacteremia, and cases without bacteremia as controls. In 475 LT recipients, there were 152 (32.0%) patients with gram-negative bacillus bacteremia in the first 6 months after LT. Out of 152 patients, there were 225 bacteremic episodes, which accounted for 69.7% in a total 323 bacteremic episodes. A total of 190 bacteremic episodes were caused by Stenotrophomonas maltophilia, Enterobacteriaceae, Ochrobactrum anthropi, Pseudomonas, and Acinetobacter baumanii, all of which were the most frequent gram-negative isolates in this study, and MDR bacilli constituted 56.3%. The most frequent source was intravascular catheters. There were 70 patients with MDR gram-negative bacillus bacteremia. Independent risk factors for bacteremia due to MDR gram-negative bacillus were as follows: post-LT abdominal infection (P<0.0001, odds ratio [OR] 0.066, 95% confidence interval [CI] 0.019-0.226), post-LT reoperative episodes (P<0.0001, OR 10.505, 95% CI 3.055-36.121), or one or more episodes of acute rejection (P=0.042, OR 4.457, 95% CI 0.988-20.103). In the first 6 months after LT, MDR gram-negative bacillus bacteremia-related mortality was significantly higher than that due to antibiotic-susceptible bacillus (38.6% vs. 14.6%, P<0.001). Post-LT bacteremias caused by MDR gram-negative bacilli are common, and associated with allograft acute rejection, post-LT reoperation, and abdominal infection. The increasing isolates of MDR gram-negative bacilli pose a great challenge for clinical treatment.

High Frequency of Multidrug-Resistant Gram-Negative Rods in 2 Neonatal Intensive Care Units in the Philippines

Although hospital-acquired infections appear to be a growing threat to the survival of newborns in the developing world, the epidemiology of this problem remains poorly characterized. During a 10-month period, we conducted prospective longitudinal surveillance for colonization and bloodstream infection caused by gram-negative rods among all infants hospitalized in the 2 largest neonatal intensive care units in Manila, the Philippines. We determined antibiotic susceptibilities and calculated adjusted odds ratios for risk factors for bacteremia by means of multivariate logistic regression. Of 1,831 neonates enrolled during a 10-month period, 1,017 (55.5%) became newly colonized and 358 (19.6%) became bacteremic with a drug-resistant gram-negative rod, most commonly Klebsiella species, Enterobacter species, Acinetobacter species, and Pseudomonas aeruginosa. Of the invasive isolates, 20% were resistant to imipenem, 41% to trimethoprim-sulfamethoxazole, 52% to amikacin, 63% to ampicillin-sulbactam, 67% to ceftazidime, and 80% to tobramycin. The factors significantly associated with an increased risk of bacteremia were mechanical ventilation and prematurity. Additionally, colonization with a drug-resistant gram-negative rod was an independent risk factor for bacteremia (odds ratio, 1.4 [95% confidence interval, 1.0-1.9]). Colonization with a drug-resistant gram-negative rod was an independent risk factor for sepsis. If our data are typical, the unusually high intensity of colonization pressure and disease caused by multidrug-resistant gram-negative rods at these 2 neonatal intensive care units indicates an emerging healthcare crisis in the developing world. Improved infection control methods are therefore critically needed in developing countries.

Risk Index Score for Bacteremia in Febrile Neutropenic Episodes in Children with Malignancies

BACKGROUND: Nowadays febrile neutropenia is regarded as heterogeneous syndrome and adequate risk stratification of patients as a basis for tailoring empiric antibiotic therapy is attempted. We conducted this prospective study to determine risk factors for bacteremia in febrile neutropenic children that could be assessed in the first days from the onset of fever and based on logistic regression analysis to construct a risk index score for prediction of bacteremia.MATERIAL AND METHODS: We studied prospectively 199 consecutive episodes of febrile neutropenia for a 4-years period (2000 – 2004), occurring in 80 children with malignancies, treated by conventional chemotherapy. A standardized computer database with a set of variables for each febrile neutropenic episode was used. C-reactive protein was measured at the first fever and depending on its duration - on the 3-rd and 5-th day from the beginning of antibiotic therapy by immunoturbidimetric method. At the onset of fever and before initiation of antibiotic therapy blood cultures were drawn and injected directly into a culture bottle BACTEC Peds plus.RESULTS: By multivariate logistic regression analysis we determined 5 variables as independent risk factors for bacteremia: the underlying malignant disease (leukemia, NHL-gr.IV), chills, perianal cellulitis, presence of central venous catheter and degree of CRP rise ≥34.5 mg/L between the onset of fever and the 3rd day of empiric antibiotic therapy. This logistic regression model has sensitivity of 93%, specificity of 25%, negative predictive value of 89% and positive predictive value of 36% for the presence of bacteremia (Chi-square: 44, −2 log likelihood:200, Cox & Snell R square: 0.2).CONCLUSIONS: The present prospective study is characterized by prevalence of hematologic malignancies and relatively high frequency of bacteremia. We identified a low-risk group of 19.1%, comparable to the reported by other groups. Based on the statistical significance of serial measurement of C-reactive protein, which allows definite risk stratification of febrile neutropenic episodes on the 3rd day from the onset of fever, we would recommend sequential empiric antibiotic approach with switch to oral or even outpatient treatment in the low-risk group on the 3rd day.

Bacteremia in Malawian Children with Severe Malaria: Prevalence, Etiology, HIV Coinfection, and Outcome

Previous prospective studies of bacteremia in African children with severe malaria have mainly included children with cerebral malaria, and no study has examined the impact of human immunodeficiency virus (HIV) infection. We examined the prevalence and etiology of bacteremia and the impact of HIV infection on bacteremia in Malawian children with severe malaria, as well as the impact of bacteremia and HIV infection on outcome. From 1996 until 2005, blood for culture was obtained on admission from all children admitted with severe malaria during the rainy season to the Paediatric Research Ward at the Queen Elizabeth Central Hospital in Blantyre, Malawi. HIV testing was performed prospectively from 2001 to 2005 and retrospectively for those admitted from 1996 to 2000. Multivariate regression analysis examined independent risk factors for bacteremia and death. Sixty-four (4.6%) of 1388 children with severe malaria had bacteremia; nontyphoidal Salmonellae (NTS) accounted for 58% of all bacteremias. The prevalence of any bacteremia and of NTS bacteremia was highest in children with severe malarial anemia (11.7% and 7.6%), compared with the prevalence in children with cerebral malaria and severe anemia (4.7% and 3.8%) and in those with cerebral malaria alone (3.0% and 0.9%). HIV infection status was determined in 1119 patients. HIV prevalence was 16% (and was highest in those with severe malaria anemia, at 20.4%), but HIV infection was not significantly associated with bacteremia. Neither bacteremia nor HIV infection was associated with death. Antibiotics are not routinely indicated for children with severe malaria in this region, in which HIV is endemic. However, antibiotic therapy should be used to treat NTS infection if bacteremia is suspected in children with severe malarial anemia.