Maltophilia Bacteremia Research Articles

Stenotrophomonas maltophilia bacteremia in hemato-oncological patients

Abstract Background Stenotrophomonas maltophilia is an increasingly common cause of bacteremia in immunocompromised patients, particularly those with underlying neutropenia. This study aims to characterize the clinical presentation, risk factors, and outcomes of Stenotrophomas maltophilia bacteremia in pediatric hemato-oncological patients. Methods We retrospectively reviewed the medical records of nine pediatric hemato-oncological patients who developed a cluster of Stenotrophomas maltophilia bacteremia at our institution from September to November in 2023. The identification and antibiotic susceptibility testing was performed by Vitek 2. Data collected included patient demographics, clinical presentation, underlying disease, treatment regimens, and outcomes. Results We identified nine cases of Stenotrophomas maltophilia bacteremia during the study period. The median age of the patients was 11 years (range 3-16 years), 7 were male. All patients had underlying hematologic malignancies (particularly acute lymphoblastic leukemia) and had profound neutropenia (ANC <100/mm3) at the time of bacteremia. The most common clinical presentation were fever (100%) and the most frequent risk factors were having a central venous catheter (CVC) (100%) and early chemotherapy treatment prior the diagnosis, median of 9 days (range 3-14 days). All patients received intravenous antibiotics, and the most commonly used agent was trimethoprim-sulfamethoxazole (TMP-SMX), the median duration of treatment was 12 days (range 7-16 days). The overall mortality rate was 11.1% on a patient with necrotizing fasciitis. Conclusion Stenotrophomas maltophilia bacteremia is a severe complication in pediatric hemato-oncological patients, considering its multidrug-resistance profile. The rise in Stenotrophomonas maltophilia isolations has triggered the implementation of outbreak investigation measures and exhibits the importance of an adequate control in central line care. Early diagnosis and appropriate antimicrobial therapy are crucial for improving outcomes.

Clinical Outcomes of Trimethoprim/Sulfamethoxazole in Critically Ill Patients with Stenotrophomonas maltophilia Bacteremia and Pneumonia Utilizing Renal Replacement Therapies.

Background: The clinical outcomes of usual doses of Trimethoprim-sulfamethoxazole (TMP/SMZ) for treating S. maltophilia in critically ill patients on renal replacement therapies (RRT) have not been established. We sought to assess the clinical outcomes of TMP/SMZ in patients with sepsis utilizing RRT. Methods: A retrospective study was performed on all critically ill adult patients with S. maltophilia infections who received RRT between May 2015 and January 2022. The primary endpoint was clinical cure while the secondary endpoints were microbiologic cure, 30-day infection recurrence, and mortality. Results: Forty-five subjects met the inclusion criteria. The median age was 70.0 [interquartile range (IQR): 63.5-77] years, 57.8% were males, and the median body mass index was 25.7 [IQR: 22-30.2] kg/m2. Clinical success and failure were reported in 18 (40%) and 27 (60%) cases, respectively. There was no significant difference between the 30-day reinfection rates of both groups; however, mortality was significantly higher in the clinical failure group, involving 12 patients (44.4%), versus none in the clinical success group (p = 0.001). The median daily dose of TMP/SMZ upon continuous veno-venous hemofiltration was 1064 [IQR: 776-1380] mg in the clinical cure group vs. 768 [IQR:540-1200] mg in the clinical failure group (p = 0.035). Meanwhile, the median dose for those who received intermittent hemodialysis was 500 [IQR: 320-928] mg in the clinical success group compared to 640 [IQR: 360-1005] mg in the clinical failure group (p = 0.372). A total of 55% experienced thrombocytopenia, 42% hyperkalemia, and 2.2% neutropenia. The multivariable logistic regression analysis showed that the total daily dose at therapy initiation was the only independent factor associated with clinical success after adjusting for different variables including the body mass index [Odds ratio 1.004; 95% confidence interval: (1-1.007), p = 0.044]. Conclusions: Although the S. maltophilia isolates were reported as susceptible, TMP/SMZ with conventional doses to treat bacteremia and pneumonia in critically ill patients utilizing RRT was associated with high rates of clinical and microbiologic failure as well as with mortality. Larger outcomes and pharmacokinetics studies are needed to confirm our findings.

Hemorrhagic Pneumonia Caused by Stenotrophomonas maltophilia in Patients with Hematologic Malignancies-A Systematic Review and Meta-Analysis.

Background and Objectives: There is a need for information regarding the clinical picture of hemorrhagic pneumonia caused by Stenotrophomonas maltophilia in patients with hematologic malignancies. In this study, we aimed to investigate the risk factors associated with hemorrhagic pneumonia caused by Stenotrophomonas maltophilia. Materials and Methods: A review of the clinical picture of hemorrhagic pneumonia based on reported cases in the literature was performed. In addition, patients with hematologic malignancies who had a Stenotrophomonas maltophilia infection were included in the meta-analysis to evaluate risk factors for hemorrhagic pneumonia. Results: A total of 91 patients had hemorrhagic pneumonia. Acute myeloid leukemia was present in 57 patients (62.6%). Those with bacteremia accounted for 94%, while those with neutropenia accounted for 95% and those with thrombocytopenia accounted for 86.7%. Hemorrhagic pneumonia was a risk factor for mortality of Stenotrophomonas maltophilia infection in patients with hematologic malignancies. Neutropenia and thrombocytopenia were identified as risk factors for hemorrhagic pneumonia. Conclusions: Stenotrophomonas maltophilia bacteremia with hemorrhagic pneumonia in patients with hematologic malignancies is a situation with rapid development and high mortality. Neutropenia and thrombocytopenia were risk factors for hemorrhagic pneumonia in patients with hematologic malignancies and with Stenotrophomonas maltophilia bacteremia; thus, these patients should be managed with caution.

Clinico-epidemiological Analysis of Stenotrophomonas Maltophilia Bacteraemia, its Associated Risk Factors and Outcome in Patients Admitted at a Tertiary Care Centre in Northern India- A Retrospective Cohort Study

Introduction: Stenotrophomonas maltophilia is a Gram-negative, motile, and glucose non fermenting bacterium commonly found in hospital settings. It poses a significant risk to immunocompromised individuals, often causing nosocomial infections. Aim: To identify the risk factors associated with Stenotrophomonas maltophilia bacteraemia and compare the factors influencing patient survival and mortality. Materials and Methods: Clinical and laboratory data from 39 cases of Stenotrophomonas bacteraemia encountered between July 2021 and July 2022 in the Department of Microbiology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, Uttar Pradesh, India, were analysed in the present retrospective study in August 2022. The study included all cultures positive for S. maltophilia bacteraemia, identified through Matrix-assisted Laser Desorption Ionisation Time- Of-Flight Mass Spectrometry (MALDI-TOF-MS). Antibiotic susceptibility testing was performed using the Kirby-Bauer disk diffusion method, following the Clinical and Laboratory Standards Institute (CLSI) guidelines. Statistical analysis and outcome assessment were conducted using Statistical Package for Social Sciences (SPSS) version 20.0. Results: Clinical data from all 39 bacteraemia patients were extracted from the hospital information system for analysis. The mean age of the patients included in the present study was 46.0±20.29 years, with a male predominance of 27 (69.23%). The most common risk factors associated with S. maltophilia bacteraemia were the presence of an indwelling catheter in 21/39 cases (53.8%) and co-existing pulmonary infections in 18/39 cases (46.2%). S. maltophilia isolates exhibited high susceptibility to Minocycline (94.87%), Ticarcillin-Clavulanic acid (87.18%), Levofloxacin (84.62%), and Cotrimoxazole (84.62%). The 30-day mortality rate was reported as 28.20% (11/39). Conclusion: S. maltophilia can cause various infections in immunocompromised patients. The appropriate use of empirical antibiotics and strict adherence to infection control measures can reduce hospital stays, as well as 14-day and 30- day mortality rates among affected patients.

239. Comparing Alternative Treatment Options for Stenotrophomonas maltophilia bacteremia

Abstract Background Stenotrophomonas maltophilia can cause nosocomial infections in immunocompromised hosts and patients with indwelling devices or broad-spectrum antibiotic exposure. Treatment of S maltophilia infections poses a challenge due to intrinsic resistance mechanisms, including inducible L1 metallo and L2 cephalosporinase beta-lactamases. Trimethoprim-sulfamethoxazole (SXT) is recognized as the agent of choice for S maltophilia infections. Outcomes with alternative antimicrobials are not well described. Methods We conducted a retrospective study of adults with positive blood cultures with S maltophilia who received ≥48h of directed antimicrobials at our institution between 3/2013 and 6/2022. Patients were stratified by their antimicrobial treatment, including levofloxacin, SXT, minocycline, ceftazidime, or combination therapy. The primary outcome was 30d all-cause mortality. Secondary outcomes were microbiological and clinical cure. Microbiological failure was defined as blood cultures growing S maltophilia during or within 7d of discontinuing therapy. Clinical failure was defined as a lack of resolution of signs or symptoms of infection requiring therapy adjustment. Results Of 67 patients with positive S maltophilia blood cultures, 53 patients treated with levofloxacin (n = 27), SXT (n = 10), minocycline (n = 8), combination (n = 5) or ceftazidime (n = 3) were included. The remaining 14 patients were excluded for receiving < 48h of therapy. The median Charlson comorbidity index was 4 [IQR 3-6]. The most common source of bacteremia was catheter-related (n = 27). Overall, 30d mortality was 26.4%. There was no significant difference in 30d mortality among patients treated with levofloxacin, SXT, minocycline, combination or ceftazidime (p = 0.23). Interestingly, patients with monomicrobial S maltophilia bacteremia had statistically higher 30d mortality (35.3% versus 11.8%, p < 0.05). Microbiological and clinical cure rates were similar between treatment groups (p = 0.06 and p = 0.16, respectively). Conclusion Treatment options for S maltophilia bacteremia resulted in similar 30d mortality; however, findings were limited by the small sample size. Larger, prospective studies are warranted to detect differences in treatment alternatives. Disclosures All Authors: No reported disclosures

First case of persistent Stenotrophomonas maltophilia bacteraemia due to septic thrombosis successfully treated with a cefiderocol-containing regimen

There is scarce evidence in literature of what should be the best antimicrobial treatment for bloodstream infections (BSIs) sustained by Stenotrophomonas maltophilia, a peculiar pathogen that intrinsically withstands to most of the available antibiotics. Here, we describe a challenging case of a persistent S. maltophilia BSI due to septic thrombosis successfully treated with the addition of the novel siderophore cephalosporin cefiderocol to an only partially effective levofloxacin regimen. Additionally, an intra-lock therapy with trimethoprim/sulfamethoxazole was selected as a strategy to prevent recurrence of infection since complete source control was not possible. The serum bactericidal assay was also used to corroborate the in vivo efficacy of the adopted combination therapy.

Stenotrophomonas maltophilia Bacteremia: From Diagnosis to Treatment.

There are many difficulties in diagnosing and treating Stenotrophomonas maltophilia bacteremia. In this study, we aimed to evaluate "true" and "false-positive bacteremia" and assess mortality risk factors and the impact of different treatment regimens. Hospitalized adult patients with S. maltophilia-positive blood cultures were assessed by a two-stage analysis. First, the clinical significance of blood cultures was assessed, and patients were divided into "true" and "false-positive bacteremia" groups. Then, excluding false positives, we analyzed the antimicrobial regimens and the factors associated with 28-day mortality in true bacteremia cases performing univariate and multivariate analyses. The study included 127 out of 138 patients with S. maltophilia bacteremia. True bacteremia was identified in 51.2% and false-positive bacteremia in 48.8% of patients. In the true bacteremia group, hypotension, nosocomial bacteremia, concomitant infections, a source of bacteremia, two positive blood culture sets, and 28-day mortality were more common. The 28-day mortality was 50.7% among true bacteremia cases. In multivariate analysis, age and solid tumor were the independent predictors of 28-day mortality. Early effective antimicrobial therapy and different antimicrobial regimens, including trimethoprim-sulfamethoxazole (SXT), fluoroquinolones (FQs), and tigecycline (TGC), did not have any significant impact on survival. Patients with S. maltophilia bacteremia should first be assessed regarding clinical significance. Clinical findings, the presence of multiple positive blood culture sets and the primary sources of bacteremia are useful parameters while discriminating true from false-positive bacteremia. Patients with advanced age and solid tumors should be followed carefully in terms of mortality. Antimicrobial regimens, including SXT, FQs, or TGC, can be preferred in patients with S. maltophilia bacteremia considering antimicrobial resistance and adverse effects or toxicity.

Risk Factors for Mortality in Patients with Stenotrophomonas maltophilia Bloodstream Infections in Immunocompetent Patients.

This study aimed to evaluate bloodstream infections caused by Stenotrophomonas maltophilia in immunocompetent patients with respect to clinical features and risk factors for mortality. We reviewed bloodstream infections detected between January 1, 2012, and July 1, 2021, to identify nosocomial S. maltophilia bacteremia in Koşuyolu Research and Training Hospital. We identified a total of 97 patients with S. maltophilia bloodstream infections. Of these, 17 patients were excluded because of community-acquired infections (n=9), contamination with S. maltophilia (n=3), and insufficient data (n=5), with 80 (57.5% males) patients remaining for analysis. The source of infection was the respiratory tract in 28 (35%) patients. A central venous catheter was used in 60 (75%) patients, which required replacement in 23 patients within five days after detecting S. maltophilia bacteremia. On antimicrobial susceptibility testing, 71 strains were found to be susceptible and 9 (11.3%) resistant to trimethoprim-sulfamethoxazole. Thirty-day mortality was 33.8%. Non-survivors differed significantly from survivors with respect to higher rates of central venous catheters ( p=0.020), mechanical ventilation (p=0.006), urinary catheters (p=0.021), septic shock (p=0.001), hypoalbuminemia (p=0.026) and thrombocytopenia (p =0.039). S. maltophilia bacteremia was independently associated with mortality in patients with hypoalbuminemia, and replacement of central venous catheters had a protective role in reducing mortality. As with other bacterial infections, S. maltophilia bacteremia is associated with a considerably high mortality rate in patients with cardiac conditions. The replacement of the catheter seems to play a beneficial role in 30-day survival.

Risk Factors for Mortality in Hospitalized Patients with Stenotrophomonas maltophilia Bacteremia.

ObjectiveStenotrophomonas maltophilia (S. maltophilia) is an opportunistic and nosocomial pathogen with high mortality. And it has intrinsic resistance to a number of antibiotics classes. In this study, we investigated risk factors for death due to S. maltophilia bacteremia.MethodsA retrospective cohort study was conducted at a tertiary-care hospital in Beijing, China. The patients from the hospital database with S. maltophilia bacteremia between January 2011 and December 2020 were investigated. Univariate and multivariate analyses were performed to identify factors associated with mortality.Results51 patients with S. maltophilia bacteremia were identified. The mortality rate was 37.3%. Based on the univariate analysis, pulmonary disease (P=0.019), chronic kidney disease (P=0.014), shock (P=0.002), foley catheter (P=0.011), the Acute Physiology and Chronic Health Evaluation II (APACHE II) score (P<0.001), procalcitonin (PCT) (P=0.045) and using antifungal agent (P=0.033) were significantly related to mortality. Based on the multivariate analysis, the APACHE II score (odds ratio [OR] =1.211; 95% confidence interval [CI]: 1.061, 1.382; P=0.005) was independent factor associated with mortality. S. maltophilia was the most susceptible to minocycline (94.7%), followed by trimethoprim and sulfamethoxazole (TMP/SMX, 92.2%).ConclusionOur findings suggested that the APACHE II score was a significantly independent predictor in S. maltophilia bacteremia patients. The use of TMP/SMX or minocycline might be the first choice for the treatment of S. maltophilia bacteremia.

Clinical Characteristics, Outcomes, and Risk Factors for Mortality in Patients with Stenotrophomonas maltophilia Bacteremia.

This study aimed to establish the clinical features, outcomes, and factors associated with mortality in patients with Stenotrophomonas maltophilia (S. maltophilia) septicemia. The characteristics and outcome data used in this retrospective study were collected from medical records at Songklanagarind Hospital. Risk factors for survival were analyzed using χ2-tests, Kaplan–Meier curves, and Cox regression. A total of 117 patients with S. maltophilia bacteremia were analyzed. The patients’ median age was 45 years, 77 (70%) were male, 105 (90%) had comorbidities, 112 (96%) had previously undergone carbapenem therapy, and over half of the patients were on invasive medical devices. Trimethoprim-sulfamethoxazole (TMP-SMX) and fluoroquinolone showed high susceptibility rates to S. maltophilia, with 93% and 88% susceptibility, respectively. Patients who received appropriate empirical antibiotic treatment had significantly reduced 14-day, 30-day, and in-hospital mortality rates than those who did not (p < 0.001). The days of hospital stay and costs for those who received appropriate and inappropriate empirical antimicrobial treatment were 21 and 34 days (p < 0.001) and 142,463 and 185,663 baht, respectively (p < 0.002). Our results suggest that an appropriate empirical antibiotic(s) is significantly associated with lower 30-day mortality in hospitalized patients with S. maltophilia septicemia.

Healthcare-Associated Stenotrophomonas maltophilia Bacteraemia: Retrospective Evaluation of Treatment and Outcome.

IntroductionStenotrophomonas maltophilia (SM) is one of the common gram-negative pathogens that cause nosocomial infections. The aim of the present study is to evaluate the treatment and outcome of SM bacteraemia.Materials and MethodsWe retrospectively evaluated antimicrobial treatment in adult patients with nosocomial SM bacteraemia, with the 14th and 30th-day mortality as the outcome.ResultsIn total, 140 adult patients with SM bacteraemia who were diagnosed between January 1, 2002, and December 31, 2016 were enrolled in the present study. Seventy-one (50.7%) patients were in the intensive care unit (ICU). The 14th and the 30th-day mortality rates were 32.9% (n=46) and 45.7% (n=64), respectively. Female sex (OR, 7.47; 95% CI 1.61-34.47, p<0.01), steroid use within the last month (OR, 10.2; 95% CI 1.27-82.27, p=0.029), Pittsburgh bacteraemia score (PBS) ≥4 (OR, 39.9; 95% CI 4.96-321.32, p<0.001) and solid organ malignancy (OR, 9.6; 95% CI 1.73-53.72, p<0.01) were independent risk factors for 14th day mortality. Removal of the catheter was an independent protective factor for both 14th (OR, 0.05; 95% CI 0.22-0.010, p<0.001) and 30th day (OR, 0.039;95% CI 0.164-0.009, p<0.001) mortality. We did not detect any difference between treatment regimens including trimethoprim-sulfamethoxazole (TMP/SMX) or levofloxacin in terms of mortality. We found that TMP/SMX and levofloxacin combination did not significantly improve patient prognosis.Conclusion Due to the high mortality rates associated with nosocomial SM bacteraemia, adequate antibiotic therapy should be initiated immediately in the suspicion of infection, and prompt removal of any indwelling central venous catheter is important.

Stenotrophomonas maltophilia bacteraemia: 61 cases in a tertiary hospital in Denmark

Background Stenotrophomonas maltophilia is an opportunistic pathogen and a dreaded cause of bacteraemia with 30-day mortality rates ranging from 14 to 69%. The purpose of this cohort study was to evaluate outcomes of S. maltophilia bacteraemia, at Rigshospitalet, a tertiary hospital in Copenhagen, Denmark. Methods We included all patients with a blood culture positive for S. maltophilia, from January 1, 2015 to April 1, 2020. We extracted data on antimicrobial susceptibility, treatment, central venous catheter intervention and severe haematological disease. Results Sixty-one cases of S. maltophilia bacteraemia were identified. The overall 90-day mortality was 18%. Sixty percent of patients had a central venous catheter intervention performed. Seventy-nine percent of patients were treated with trimethoprim/sulfamethoxazole (TMP/SMX). Patients with central venous catheter intervention had significantly better survival than those without (HR: 0.16 [95% CI: 0.03–0.73]). Severe haematological disease and patients, who received intensive care unit (ICU) care, were at higher risk of death than other patients (HR: 5.93 [95% CI: 1.18 − 29.94] and HR: 8.37 [95% CI: 1.79 − 39.20], respectively). We found no evidence that any antibiotic regime was superior with regard to 90-day mortality. Conclusions We did not find evidence to support a change in the current standard-of-care regimen of TMP/SMX and CVC removal. Larger clinical trials are needed to guide such recommendations.

Stenotrophomonas maltophilia bacteremia in children: risk factors and mortality rate

PurposeStenotrophomonas maltophilia (S. maltophilia) is an opportunistic and nosocomial pathogen that can cause an invasive and fatal infection, particularly in hospitalized and immunocompromised patients. However, little is known about the impact of S. maltophilia bacteremia in pediatric patients. Therefore, we aimed to identify risk factors for mortality, antibiotics susceptibility to S. maltophilia, and mortality rates in pediatric patients with S. maltophilia bacteremia.MethodsWe conducted a retrospective cohort study by identifying all S. maltophilia positive blood cultures in the microbiology laboratory database between January 2007 and December 2018 from hospitalized pediatric patients (age 1–14 years). After identifying patients with S. maltophilia bacteremia, medical charts were reviewed for demographics, clinical data, and outcomes within seven days of bacteremia diagnosis. Risk factors associated with mortality in S. maltophilia bacteremia patients were determined using univariate and multivariate analyses.FindingsSixty-eight pediatric patients with S. maltophilia bacteremia were identified. All infections were nosocomial infections, and (88.2%) bacteremia cases were catheter-related bloodstream infections. On multivariate analysis, ICU admission prior to bacteremia episode and neutropenia were the major risk factors associated with mortality. S. maltophilia was the most susceptible to trimethoprim and sulfamethoxazole (TMP/SMX, 94.1%), followed by levofloxacin (85.7%). The overall mortality rate within seven days of S. maltophilia bacteremia diagnosis was 33.8%.ConclusionS. maltophilia bacteremia is a devastating emerging infection associated with high mortality among hospitalized children. Therefore, early diagnosis and prompt management based on local susceptibility data are crucial. Various risk factors, especially ICU admission prior to bacteremia episode and neutropenia, are associated with S. maltophilia bacteremia mortality.

Risk Factors and Mortality in Pediatric Patients with Stenotrophomonas maltophilia Bacteremia

Background:Stenotrophomonas maltophilia (S. maltophilia) is an opportunistic and nosocomial pathogen that can cause an invasive and fatal infection, particularly in hospitalized and immunocompromised patients. However, little is known about the impact of S. maltophilia bacteremia in pediatric patients. Therefore, we aimed to identify risk factors for mortality, antibiotic susceptibility of S. maltophilia, and mortality rates in pediatric patients with S. maltophilia bacteremia. Methods: We conducted a retrospective cohort study by identifying all S. maltophilia–positive blood cultures in the microbiology laboratory database between January 2007 and December 2018 from hospitalized pediatric patients (age, 1–14 years) at King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia. After identifying patients with S. maltophilia bacteremia, medical charts were reviewed for demographics, clinical data, and outcome within 7 days of bacteremia diagnosis. Risk factors associated with mortality in S. maltophilia bacteremia patients were determined using univariate and multivariate analyses. Results: Overall, 68% of pediatric patients with S. maltophilia bacteremia were identified. The most common underlying primary diagnoses were malignancy (29.4%), congenital heart diseases (16.2%), anemia (14.7%), and primary immunodeficiency (11.8%). All infections were nosocomial infections, and (88.2%) bacteremia cases were central-line–associated bloodstream infections. The risk factors associated with mortality as determined by univariate analysis were ICU admission (P &lt; .001), intubation (P = .001), neutropenia (P = .008), prior use of carbapenem (P = .002), thrombocytopenia (P = .006), and respiratory colonization (P &lt; .001). On multivariate analysis, ICU admission (P = .007; 95% CI, 0.003–0.406) and neutropenia (P = .009; 95% CI, 0.013–0.537) were the major risk factors associated with mortality. S. maltophilia was the most susceptible to trimethoprim and sulfamethoxazole (TMP/SMX, 94.1%), followed by levofloxacin (85.7%). In addition, 36 patients received TMP/SMX as monotherapy, and 11 patients received it in combination with other antibiotics (fluoroquinolone, ceftazidime, or aminoglycoside). Hence, no statistically significant difference was observed in patient mortality. The overall mortality rate within 7 days of S. maltophilia bacteremia diagnosis was 33.8%. Conclusions:S. maltophilia bacteremia is a devastating emerging infection associated with high mortality among hospitalized children. Therefore, early diagnosis and prompt management based on local susceptibility data are crucial. Various risk factors, especially ICU admission and neutropenia, are associated with S. maltophilia bacteremia mortality.Funding: NoneDisclosures: None

Stenotrophomonas maltophilia bacteremia in children - A 10-year analysis.

Stenotrophomonas maltophilia is a multidrug-resistant, Gramnegative, and biofilm-forming pathogen. Information is limited concerning S. maltophilia bacteremia in children. Clinical data and microbiological test results collected in a tertiary children's hospital over a ten-year period were reviewed. Children 0-18 years old who had positive clinical specimen, blood and/or catheter cultures were included. We identified 20 S. maltophilia isolates from 12 pediatric patients with confirmed infections. The median age was 28 months (range: 3.1-187.3). The rate of previous use of antimicrobial therapy was 83 %. The median antibiotic number was 3 (range: 0-7) within 30 days prior to onset of S. maltophilia bacteremia. Catheter related infection was the main infectious source (66.6 %). The mortality rate was 33.3 %. The death of two non-survivors was associated with pneumonia. S. maltophilia should be considered a breakthrough agent for bacteremia in children with underlying disease exposed to broad-spectrum antibiotics during long-term hospitalization.

Next-generation sequencing of microbial cell-free DNA for rapid noninvasive diagnosis of infectious diseases in immunocompromised hosts.

Background: Cell-free DNA (cfDNA) sequencing has emerged as an effective laboratory method for rapid and noninvasive diagnosis in prenatal screening testing, organ transplant rejection screening, and oncology liquid biopsies but clinical experience for use of this technology in diagnostic evaluation of infections in immunocompromised hosts is limited. Methods: We conducted an exploratory study using next-generation sequencing (NGS) for detection of microbial cfDNA in a cohort of ten immunocompromised patients with febrile neutropenia, pneumonia or intra-abdominal infection. Results: Pathogen identification by cfDNA NGS demonstrated positive agreement with conventional diagnostic laboratory methods in 7 (70%) cases, including patients with proven/probable invasive aspergillosis, Pneumocystis jirovecii pneumonia, Stenotrophomonas maltophilia bacteremia, Cytomegalovirus and Adenovirus viremia. NGS results were discordant in 3 (30%) cases including two patients with culture negative sepsis who had undergone hematopoietic stem cell transplant in whom cfDNA testing identified the potential etiological agent of sepsis; and one kidney transplant recipient with invasive aspergillosis who had received >6 months of antifungal therapy prior to NGS testing. Conclusion: These observations support the clinical utility of measurement of microbial cfDNA sequencing from peripheral blood for rapid noninvasive diagnosis of infections in immunocompromised hosts. Larger studies are needed.

Stenotrophomonas Bacteremia Antibiotic Susceptibility and Prognostic Determinants: Mayo Clinic 10-Year Experience.

Background Stenotrophomonas maltophilia is a gram-negative, opportunistic infection that is usually hospital-acquired and associated with high morbidity and mortality. The reported increase in S. maltophilia infections is presumed to be due to an increase in the population at risk.MethodsWe retrospectively reviewed 10-year data for S. maltophilia bacteremia in hospitalized adults at our institution to determine the population at risk, sources of infection, common complications, antimicrobial susceptibility profiles, and clinical outcome trends over the past decade.ResultsAmong the 98 patients analyzed, the most common source of infection was catheter-related (62, 63.3%). Most isolates (61, 65%) were resistant to ceftazidime; fewer were resistant to trimethoprim-sulfamethoxazole (TMP-SMX; 2, 2.1%) and levofloxacin (22, 23.4%). All-cause in-hospital mortality was 29.6% (29 patients). The highest mortality, 53.8%, was observed in pulmonary sources of bacteremia.ConclusionsAlthough TMP-SMX continues to have reliable activity in our cohort, we noted resistance to TMP-SMX in patients with recent TMP-SMX exposure, including a case with developing resistance to TMP-SMX while on therapy.

Clinical Features, Outcomes, and Risk Factors of Bloodstream Infections due to Stenotrophomonas maltophilia in a Tertiary-Care Hospital of China: A Retrospective Analysis

Background. Stenotrophomonas maltophilia bacteremia (SMB) is the most perilous situation as compared to other types of S. maltophilia infection. The present study aimed to investigate the clinical features, distribution, drug resistance, and predictors of survival of SMB in a tertiary-care hospital of China. Methods. SMB that occurred in a tertiary-care hospital in Beijing, China, within 9 years (2010–2018) was investigated in a retrospective study. Demographics, incidence, commodities, drug resistance, mortality, as well as antibiotics administration were summarized according to the electronic medical records. The risk factors for survival were analyzed by Chi-square test, Kaplan–Meier curve and Cox regression. Results. A total of 76 episodes of SMB were analyzed. The overall incidence of SMB fluctuated from 3.4 to 15.4 episodes per 1000 admissions over 9 years. Malignancy was the most common comorbidity. High in vitro sensitivity was observed to minocycline (96.1%), levofloxacin (81.6%), and trimethoprim-sulfamethoxazole (89.5%). Central venous catheter (CVC) (p = 0.004), mechanical ventilation (MV) (p = 0.006), hemodialysis (p = 0.024), and septic shock (p = 0.016) were significantly different between survival and death group. The 30-day mortality was 34.2% within 30 days after confirmation of blood culture. Factors such as hemodialysis (OR 0.287, 95% CI: 0.084–0.977, p = 0.046), T-tube (OR 0.160, 95% CI: 0.029–0.881, p = 0.035), and septic shock (OR 0.234, 95% CI: 0.076–0.719, p = 0.011) were associated with survival. Conclusions. S. maltophilia is the major nosocomial blood stream infectious pathogenic bacteria. Trimethoprim-sulfamethoxazole and minocycline are optimal antibiotics for the treatment of SMB. T-tube, hemodialysis, and septic shock were the risk factors associated with survival of SMB patients.

Next-generation sequencing of microbial cell-free DNA for rapid noninvasive diagnosis of infectious diseases in immunocompromised hosts

Background: Cell-free DNA (cfDNA) sequencing has emerged as an effective laboratory method for rapid and noninvasive diagnosis in prenatal screening testing, organ transplant rejection screening, and oncology liquid biopsies but clinical experience for use of this technology in diagnostic evaluation of infections in immunocompromised hosts is limited. Methods: We conducted an exploratory study using next-generation sequencing (NGS) for detection of microbial cfDNA in a cohort of ten immunocompromised patients with febrile neutropenia, pneumonia or intra-abdominal infection. Results: Pathogen identification by cfDNA NGS demonstrated positive agreement with conventional diagnostic laboratory methods in 7 (70%) cases, including patients with proven/probable invasive aspergillosis, Pneumocystis jirovecii pneumonia, Stenotrophomonas maltophilia bacteremia, Cytomegalovirus and Adenovirus viremia. NGS results were discordant in 3 (30%) cases including two patients with culture negative sepsis who had undergone hematopoietic stem cell transplant in whom cfDNA testing identified the etiological agent of sepsis; and one kidney transplant recipient with invasive aspergillosis who had received &gt;6 months of antifungal therapy prior to NGS testing. Conclusion: These observations support the clinical utility of measurement of microbial cfDNA sequencing from peripheral blood for rapid noninvasive diagnosis of infections in immunocompromised hosts. Larger studies are needed.

Next-generation sequencing of microbial cell-free DNA for rapid noninvasive diagnosis of infectious diseases in immunocompromised hosts

Background: Cell-free DNA (cfDNA) sequencing has emerged as an effective laboratory method for rapid and noninvasive diagnosis in prenatal screening testing, organ transplant rejection screening, and oncology liquid biopsies but clinical experience for use of this technology in diagnostic evaluation of infections in immunocompromised hosts is limited. Methods: We conducted an exploratory study using next-generation sequencing (NGS) for detection of microbial cfDNA in a cohort of ten immunocompromised patients with febrile neutropenia, pneumonia or intra-abdominal infection. Results: Pathogen identification by cfDNA NGS demonstrated positive agreement with conventional diagnostic laboratory methods in 7 (70%) cases, including patients with proven/probable invasive aspergillosis, Pneumocystis jirovecii pneumonia, Stenotrophomonas maltophilia bacteremia, Cytomegalovirus and Adenovirus viremia. NGS results were discordant in 3 (30%) cases including two patients with culture negative sepsis who had undergone hematopoietic stem cell transplant in whom cfDNA testing identified the potential etiological agent of sepsis; and one kidney transplant recipient with invasive aspergillosis who had received >6 months of antifungal therapy prior to NGS testing. Conclusion: These observations support the clinical utility of measurement of microbial cfDNA sequencing from peripheral blood for rapid noninvasive diagnosis of infections in immunocompromised hosts. Larger studies are needed.