Maltophilia Bacteremia Research Articles

Evaluation of treatment outcomes for Stenotrophomonas maltophilia bacteraemia

The goal of this study was to retrospectively collect data about treatment outcomes in patients diagnosed with Stenotrophomonas maltophilia bacteraemia over a period of 20 years and evaluate these data with respect to the efficacy of treatment options. The setting was a 700-bed tertiary care hospital in a large urban area. Hospital databases and medical records provided information about episodes of S. maltophilia, patient characteristics and treatment outcomes. Patients with at least one positive blood culture for S. maltophilia were included in the study. Data were analysed with respect to clinical improvement and mortality ≤30 days after the onset of infection. We compared patient characteristics, laboratory values and treatments by using the Chi-square or Fisher's exact tests and the Mann-Whitney test. We investigated 27 patients with S. maltophilia bacteraemia. The focus of infection was a central venous catheter in 18 (67 %) cases. The 30-day mortality rate was 11 %. All patients who were treated with an antibiotic that was effective in vitro against the pathogen recovered clinically and survived ≥30 days after the onset of infection. The most frequently used antibiotic was trimethoprim-sulfamethoxazole administered alone or in combination with a fluoroquinolone. Despite the fact that S. maltophilia is resistant to multiple antibiotics, the prognosis for patients with S. maltophilia bacteraemia is good when they are treated with antibiotics that are effective against this pathogen in vitro.

Stenotrophomonas maltophilia Bacteraemia: Analysis of 33 Episodes Occurred in the ICU at the University Hospital in Sousse, Tunisia

Background: Stenotrophomonas maltophilia is a multidrug-resistant, Gram negative bacillus that has emerged as an opportunistic pathogen associated with high morbidity and mortality rates. Aim: The aim of this study is to describe the characteristics of patients with bloodstream infections due to S. maltophilia. Methods: A descriptive retrospective study was performed at the ICUs over seven-year period in a teaching hospital. Cases of SMB were identified through a review of clinical microbiology laboratory and patient’s records were retrieved for analysis. Findings: There were 22 deaths (71%) 15 ± 12 days after the bactaeremia. In our study, more than half of patients (17/31) was exposed to broad-spectrum antibiotic specifically imipinem (IMP) before their positive culture. Antibiotic susceptibility testing revealed that isolates were most sensitive to ciprofloxacin (84%) and to trimethoprim-sulfamethoxazole (71%). A probable portal of entry was identified in 27.3% of cases and 57% were catheter-related. Conclusion: Our results were similar to those described by other authors reported in the literature in the last 20 years. Prevention of S. maltophilia acquisition and infection depends on higher emphasis on control of antimicrobial consumption and consideration of environmental reservoirs.

Bloodstream infections caused by Stenotrophomonas maltophilia: a seven-year review

Stenotrophomonas maltophilia is a significant nosocomial pathogen, responsible for an increasing number of infections, particularly in immunocompromised patients. This study describes the clinical and microbiological characteristics of patients with Stenotrophomonas maltophilia bacteraemia. We reviewed the charts of 102 patients with Stenotrophomonas maltophilia bacteraemia over a seven-year period from 2001 to 2007 in two tertiary care centres in New York, USA. There were 79 episodes (77.5%) related to nosocomial acquisition, 21 (20.6%) were healthcare-associated and two episodes (2%) were community-acquired. The most common source of bacteraemia was an infected central catheter in 44 patients (43.1%); 17 (16.6%) were related to neutropenic sepsis; nine (8.8%) were from an abdominal source; six (5.9%) were from a respiratory source, and the source of the bacteraemia was unclear in 26 cases (25.5%). The majority (94.1%) of the patients had central venous access devices. Intensive care unit stay, intubation, septic shock, neutropenia at the time of bacteraemia or carbapenem antibiotic use within 30 days of the episode were associated with mortality according to univariate analysis. By multivariate analysis, hypotensive shock and carbapenem use within 30 days of the episode were factors significantly correlated with mortality. The 102 isolates were mostly susceptible in vitro to trimethoprim-sulfamethoxazole (97.1%), levofloxacin (92.9%), ceftazidime (53.0%) and ticarcillin-clavulanic acid (49.2%). Our data describe the characteristics of patients with Stenotrophomonas maltophilia bacteraemia and emphasize the importance of careful evaluation of vascular access devices in those patients.

Predictors of catheter-related gram-negative bacilli bacteraemia among cancer patients

Gram-negative bacillary bacteraemia (GNB) is associated with high morbidity and mortality among cancer patients. We conducted this study to determine the risk factors that may predict the catheter as the source of GNB in cancer patients. From July 2005 to December 2006 all 266 cancer patients with GNB and central venous catheters (CVCs) at The University of Texas M. D. Anderson Cancer Centre in Houston, were classified as catheter-related bloodstream infection (CRBSI) according to Infectious Diseases Society of America criteria. We compared clinical and microbiological features of CRBSIs and non-CRBSIs. We identified 78 CRBSIs and 126 non-CRBSIs. On univariate analysis, polymicrobial bacteraemia, Stenotrophomonas maltophilia bacteraemia, and more than 1000 CFUs in CVC blood cultures, were more common among CRBSI cases. Escherichia coli bacteraemia, haematologic cancer, neutropenia and prior antibiotic use were more common among non-CRBSI cases. On multivariate analysis, S. maltophilia bacteraemia (odds ratio (OR), 5.78; 95% confidence interval (CI), 1.47–22.78; p 0.045), polymicrobial bacteraemia (OR, 4.04; 95% CI, 1.56–10.44; p 0.042), and more than 1000 CFUs from CVC blood cultures (OR, 4.39; 95% CI, 2.02–9.27; p <0.01), were associated with CRBSI. Neutropenia was associated with non-CRBSI (OR, 0.26; 95% CI, 0.13–0.53; p <0.01). Several factors such as S. maltophilia bacteraemia, polymicrobial bacteraemia and more than 1000 CFUs from a blood culture drawn through the CVC may assist the clinicians in assessing whether an indwelling catheter is the source of a GNB and hence CVC removal may be considered.

Clinical chracteristics and prognostic factors in patients with Stenotrophomonas maltophilia bacteremia

Clinical chracteristics and prognostic factors in patients with Stenotrophomonas maltophilia bacteremia

Risk factors for mortality among patients with Stenotrophomonas maltophilia bacteremia in Tokyo, Japan, 1996–2009

Stenotrophomonas maltophilia is an important nosocomial pathogen, especially among immunocompromised patients. The objective of this study was to clarify the clinical characteristics, prognosis, and prognostic factors of patients with S. maltophilia bacteremia in Japan. The microbiology records of all patients with S. maltophilia bacteremia between January 1996 and April 2009 at Toranomon Hospital, Tokyo, Japan, were retrospectively reviewed. A total of 53 cases of bacteremia were identified. Thirty patients had an underlying hematological disorder, and 23 were receiving hematopoietic transplantation. The overall mortality rate was 51%. On univariate analysis, neutropenia (p < 0.01), the presence of a central venous catheter, and mixed infection with enterococci (p < 0.05) were significantly related to the mortality. Among these variables, neutropenia (p < 0.01) and mixed infection with enterococci (p < 0.05) were independent factors associated with mortality. In contrast, all eight patients in whom S. maltophilia was the etiologic agent of catheter-related infection survived following catheter removal. S. maltophilia is an important pathogen among immunocompromised patients, especially in the neutropenic phase or mixed infection with enterococci. If a central venous catheter was present at the onset of S. maltophilia bacteremia, the prompt removal of the catheter was important.

Stenotrophomonas maltophilia bacteraemia in 40 haematology patients: risk factors, therapy and outcome

Stenotrophomonas maltophilia bacteraemia in 40 haematology patients: risk factors, therapy and outcome

Stenotrophomonas maltophilia bacteremia in end‐stage renal disease patients receiving maintenance hemodialysis

AbstractStenotrophomonas maltophilia is typically a low‐virulence gram‐negative bacterium but can become pathogenic in patients in immunocompromised states and can cause nosocomial infections in the presence of invasive medical devices such as central venous catheters, peritoneal catheters, endotracheal/tracheostomy tubes, and urinary catheters, resulting in a variety of infections. End‐stage renal disease patients are immunocompromised, and S. maltophilia bacteremia has been reported in patients receiving peritoneal dialysis via peritoneal catheters. A significant number of patients receive hemodialysis via central venous catheters, which present a high risk for S. maltophilia infection, but to our knowledge, no case has been reported.

Stenotrophomonas maltophiliabacteraemia in Turkish children

Stenotrophomonas maltophilia is an important cause of life-threatening nosocomial infection. To evaluate the clinical features, antibiotic treatment and prognosis of S. maltophilia bacteraemia. Patients with blood cultures positive for S. maltophilia at the Children's Hospital, Ankara University Medical School between 1995 and 2005 were evaluated retrospectively. The results were compared with those of a case-control group of patients with Pseudomonas aeruginosa bacteraemia (n=33). Antibiotic susceptibilities of S. maltophilia strains were determined by disc diffusion. Susceptibility to ciprofloxacin was also determined by broth dilution. Thirty-six (2.2%) blood cultures were positive for S. maltophilia. Neutropenia was more common in the P. aeruginosa group (p=0.001). Breakthrough bacteraemia developed more commonly during carbapenem treatment in the S. maltophilia group (p=0.02). Ciprofloxacin and trimethoprim-sulfamethoxazole in combination with/without an aminoglycoside were the antibiotics most commonly selected to treat S. maltophilia bacteraemia. Mortality was more common in the P. aeruginosa (13/33) than in the S. maltophilia (2/33) group (p=0.001). According to susceptibility, determination by the disk diffusion method, beta-lactam antibiotics, aminoglycosides and chloramphenicol had little or no effect, whereas trimethoprim-sulfamethoxazole, doxycycline and fluoroquinolones were more active against S. maltophilia strains. However, ciprofloxacin susceptibility results were quite different when determined by disk diffusion (97% isolates susceptible) and broth dilution (49% isolates susceptible). Although S. maltophilia bacteraemia is rare in children, antibiotic resistance to these strains is an important problem. Tetracyclines, trimethoprim-sulfamethoxazole and fluoroquinolones are the most active agents against S. maltophilia strains.

Clinical Aspects and Risk Factors of Nosocomial Stenotrophomonas maltophilia Bacteremia Episodes in a Turkish Intensive Care Unit

Stenotrophomonas maltophilia is an important nosocomial pathogen with increasing frequency in recent years, especially in immunocompromised and clinically debilitated patients. The aim of this study is to describe the characteristics of 35 episodes of S. maltophilia bacteremia at Celal Bayar University hospital in Turkey over a 3-year period from January 2003 to December 2005. Cases were identified with microbiology laboratory records and clinical data were collected from the medical record of each patient. The source of bacteremia was central venous catheter (CVC) in 65.7% (23) and respiratory tract infection in 2.9% (1) of episodes while the source of bacteremia was unknown in 11 (31.4%) episodes of bacteremia. Factors significantly associated with mortality were age of ≥65 years, APACHE score of ≥16, the presence of the total parenteral nutrition, anemia, low creatinine clearance level and shock. The most sensitive antibiotic was found as trimethoprim-sulfamethoxazole (91.4%) in antibiotic susceptibility testing of the isolates. Susceptibilities of piperacillin-tazobactam and netilmicin which frequently used antibiotics as an empirical therapy were 62.8% and 68.6%, respectively.

Bloodstream Infection Caused by Stenotrophomonas maltophilia in Children

Stenotrophomonas maltophilia, a multidrug resistant Gram-negative pathogen, has become a more frequent cause of bloodstream infections (BSI). Little is known about development of S. maltophilia bacteremia in children. The objective of this study was to define risk factors and outcomes associated with S. maltophilia BSI in children. This was a retrospective case-control study conducted at The Children's Hospital of Philadelphia between January 1, 2000 and July 31, 2005. All patients with S. maltophilia BSI were compared with a random sample of patients with non-Stenotrophomonas Gram-negative rod BSI. Fifty-one cases and 103 control subjects were included in the study. The median patient age was 2 years (interquartile range: 1 day-8.5 years). Patients with S. maltophilia BSI were significantly more likely to have a malignancy and be coinfected with other organisms than those with other Gram-negative rod infections. On multivariate analysis, patients with S. maltophilia BSI were more likely to develop their infection in the home setting (adjusted OR, 4.18; 95% CI: 1.44-12.16; P = 0.009). Additionally, prior exposure to trimethoprim-sulfamethoxazole, receipt of steroids or other immunosuppressive medication in the 30 days preceding infection and black race were associated with the development of S. maltophilia BSI. Patients with Stenotrophomonas maltophilia BSI are more likely to have a polymicrobial infection and develop their infection in the home setting compared with patients with BSI caused by other Gram-negative rods.

Successfully treated nosocomial Stenotrophomonas maltophilia bacteremia following desensitization to trimethoprim-sulfamethoxazole

Stenotrophomonas maltophilia has emerged as an important cause of morbidity and mortality in hospitalized patients. Because trimethoprim-sulfamethoxazole (TMP-SMX) remains the most effective drug for the treatment of S. maltophilia infections, desensitization should be considered in patients with hypersensitivity to TMP-SMX.

Skin Manifestation of Stenotrophomonas maltophilia Infection – A Case Report and Review Article

Stenotrophomonas maltophilia is an aerobic gram-negative bacillus that is a frequent coloniser of fluids used in the hospital setting. It causes infection in immunosuppressed hosts, especially those who are neutropaenic, on chemotherapy and broad spectrum antibiotics. Skin and soft tissue manifestations of Stenotrophomonas maltophilia infection are becoming an increasingly recognised entity; the clinical spectrum ranges from mucocutaneous, skin to soft tissue infections. We present a case of an 8-year-old girl with acute myeloid leukaemia who developed metastatic skin lesions secondary to Stenotrophomonas maltophilia bacteraemia. The authors reviewed a total of 24 reported cases of mucocutaneous, skin and soft tissue infections by Stenotrophomonas maltophilia. The presentations include metastatic cellulitis, primary cellulitis and infected mucocutaneous ulcers. This is the first locally reported case of metastatic nodular skin lesions caused by Stenotrophomonas maltophilia bacteraemia. This is also the first reported paediatric case of embolic skin lesions caused by Stenotrophomonas maltophilia. Of the 6 cases of Stenotrophomonas maltophilia bacteraemia seen in the paediatric oncology patients from year 2000 to 2004 at our hospital, only 1 case developed metastatic skin lesions. Stenotrophomonas maltophilia skin infection should be included into the list of differential diagnoses for metastatic skin lesions in neutropaenic patients, especially with an underlying haematologic malignancy who has received recent chemotherapy and broad spectrum antibiotics. Haematologic malignancy, transplantation, neutropaenic, immunosuppressive therapy and a high severity of illness score were important prognostic factors.

Central venous catheter-related Stenotrophomonas maltophilia bacteraemia and associated relapsing bacteraemia in haematology and oncology patients

This retrospective study investigated the clinical significance and impact of Stenotrophomonas maltophilia bacteraemia in 49 haematology and oncology patients at a tertiary referral medical centre in Taipei between July 1999 and December 2003. Sixteen patients had 24 episodes of central venous catheter (CVC)-related bacteraemia, with the main clinical characteristics being a nosocomial bacteraemia (100%), preceding antibiotic therapy (94%), bacteraemia developed in a general ward (87%), immunosuppressive therapy (75%), in-situ CVC-related bacteraemia (75%), and neutropenia (63%). Only four (25%) patients had inflammatory signs at the CVC site following diagnosis of bacteraemia. Five patients had recurrent bacteraemia, with risk-factors being long-lasting (>10 days) neutropenia (p 0.036) and an initial failure to remove the CVC (p 0.001). These cases did not involve re-infection, as the same S. maltophilia strain was identified following random amplified polymorphic DNA (RAPD) analysis of the initial and subsequent isolates. However, relapses could occur after long latency periods (maximum, 200 days). Most patients were cured after removal of the CVC, even without appropriate antibiotic treatment. Physicians should have a high index of suspicion for CVC-related bacteraemia with haematology and oncology patients with CVCs and S. maltophilia bacteraemia. In addition to appropriate antibiotic therapy, removal of the CVC is crucial for successful treatment of CVC-related S. maltophilia bacteraemia and prevention of relapses.

Central venous catheter and Stenotrophomonas maltophilia bacteremia in cancer patients

Stenotrophomonas maltophilia bacteremia is frequently found in cancer patients. This study attempted to determine how often the catheters were the source of this infection and the risk factors associated with catheter-related bacteremias. The microbiology records were retrospectively reviewed of all cancer patients having S. maltophilia bacteremia and indwelling central venous catheters seen between January 1998 and January 2004. In a multivariate analysis the patients' clinical characteristics, antimicrobial therapy, outcome, and source of bacteremia that were significantly associated with definite catheter-related S. maltophilia bacteremia as opposed to secondary bacteremia were identified. A total of 217 bacteremias were identified in 207 patients: 159 (73%) were primary catheter-related (53 definite, 89 probable, and 17 possible), 11 (5%) were primary noncatheter-related, and 47 (22%) were secondary. Multivariate analysis showed the following factors to be independently associated with definite catheter-related bacteremias: 1) polymicrobial bacteremia (odds ratio [OR], 7.6; 95% confidence interval [95% CI], 1.3-45.5); 2) no prior intensive care unit admission (OR, 0.06; 95% CI, 0.005-0.578); and 3) nonneutropenic status at onset (OR, 0.07; 95% CI, 0.013-0.419). The response rate to appropriate antibiotics and catheter removal was 95% in the patients with definite catheter-related bloodstream infections, compared with only 56% in the patients with secondary bacteremias (P = .001). The majority of the S. maltophilia bacteremias occurring in cancer patients with indwelling central venous catheters appear to be catheter-related and are often polymicrobial. Catheter-related S. maltophilia bacteremias occurred more frequently in noncritically ill, nonneutropenic patients, and prompt removal of the catheter was found to be associated with a better prognosis.

Stenotrophomonas maltophilia bacteremia in burn patients

Stenotrophomonas maltophilia has been increasingly reported as a nosocomial opportunistic pathogen in debilitated patients, including burn patients. There is, however, only one published report in English that discusses S. maltophilia bacteremia in burns. We performed a retrospective chart review and statistical analysis of the incidence, the duration of hospital stays before a diagnosis of bacteremia, antimicrobial susceptibility, prognosis, and mortality risk factors in burn patients. From January 1996 to December 2004, 14 episodes of S. maltophilia bacteremia in 13 of 666 patients admitted to the burn center at our hospital were identified. The patients, nine males and four females, ranged in age from 1 to 76 years (mean: 42.9 ± 24.4 years). Eleven injuries were from flame burns and two were from scald burns. The mean total burned surface area (TBSA) was 47 ± 30.2% and mean prognostic burn index (PBI) was 81.7 ± 31.3. The average annual incidence was 2.3 episodes per 1000 admissions, and no outbreak cluster was noticed. The mean hospital stay before bacteremia was 19.8 ± 11.9 days. Most isolates were susceptible to ticarcillin-clavulanate (87.5%) and moxalactam (85.7%). The overall mortality was 30.7% (4/13) and correlated significantly with TBSA ( P < 0.01) and PBI ( P < 0.05). The incidence of S. maltophilia bacteremia was higher in hospitalized burn patients than in hospitalized non-burn patients. Different antimicrobial susceptibility patterns may exist, especially in different geographic regions. Awareness of the possibility of infection by this opportunistic pathogen and commencement of adequate antibiotics treatment, especially after 3 weeks of intensive care, should be incorporated into the strategy of treatment in major burn patients.

Which patient is a candidate for empirical therapy against Stenotrophomonas maltophilia bacteraemia? An analysis of associated risk factors in a tertiary care hospital

Stenotrophomonas maltophilia is an emerging nosocomial pathogen with a tendency to be resistant to several antibiotics commonly used to treat nosocomial infections. Early recognition of the risk factors for bacteraemia caused by S. maltophilia could potentially improve the prognosis in these cases. Most data have been obtained from a limited number of descriptive studies. In this retrospective case-control study, we investigated the risk factors for S. maltophilia bacteraemia. We compared cases with 2 different control groups; non-bacteraemic patients and those with bacteraemia caused by Escherichia coli. 37 cases were matched with 37 control patients with nosocomial E. coli bacteraemia and 74 non-bacteraemic patients. The demographic information was extracted from the chart of the patients. When the effects of multiple factors were analysed simultaneously, the presence of a central venous catheter and carbapenem use were associated with an increased risk for bacteraemia caused by S. maltophilia compared with both the non-bacteraemic and bacteraemic control groups. We found a mortality rate of 21.6% in cases vs non-bacteraemic controls; however, this was not a statistically significant difference from that observed in patients with E. coli bacteraemia.

The molecular epidemiology of Stenotrophomonas maltophilia bacteraemia in a tertiary referral hospital in the United Arab Emirates 2000–2004

BackgroundStenotrophomonas maltophilia is recognised as an important cause of nosocomial infection, especially in immunocompromised patients, resulting in significant morbidity and mortality. The treatment of S. maltophilia infection presents a therapeutic challenge. The precise modes of transmission of S. maltophilia in the hospital environment are not known and such knowledge is essential to target interventions to prevent spread. There are few published data on the patterns of nosocomial infection in the United Arab Emirates (UAE). A recent study showed that S. maltophilia is an established cause of bloodstream infection in Tawam Hospital in the UAE. Little is known about its epidemiology in the hospital.MethodsWe describe the clinical characteristics of 25 episodes of S. maltophilia bacteraemia which occurred from 2000–2004. The strains were characterised using pulsed field gel electrophoresis (PFGE).ResultsAll episodes were hospital-acquired and malignancy and central venous catheters were predisposing factors. Catheter-associated infection comprised 88% infection. Catheter removal was important for the successful management of catheter-associated infection. The results of PFGE suggested that there were as many strains as patients. S. maltophilia strains isolated from the same patient had indistinguishable PFGE profiles.ConclusionPFGE is a valid and reproducible typing method for S. maltophilia. The precise sources and modes of spread of S. maltophilia in the hospital are still not known. Knowledge that person to person transmission was not a major mode of transmission enabled infection control interventions for S. maltophilia to be targeted more effectively.

Impact of Initial Antimicrobial Therapy in Patients with Bloodstream Infections Caused by Stenotrophomonas maltophilia

The impact of inappropriate initial antimicrobial therapy on the outcomes of patients with bloodstream infections caused by antibiotic-resistant gram-negative bacilli is not well defined. Recently, in an interesting study by Kang et al., inappropriate initial antimicrobial therapy was found to be associated with an adverse outcome, particularly in patients with a high-risk source of bacteremia caused by Escherichia coli, Klebsiella pneumoniae, Enterobacter spp., and Pseudomonas aeruginosa (1). In addition to the source of bacteremia, presentation with septic shock, P. aeruginosa infection, and an increasing acute physiology, age, and chronic health evaluation (APACHE II) score were poor prognostic factors in this study. Stenotrophomonas maltophilia is an emerging nosocomial pathogen with a tendency to be resistant to several antibiotics commonly used to treat nosocomial infections. Although a recent study reported no significant difference in the outcomes of patients who received appropriate therapy and outcomes of patients who received inappropriate therapy (2), at least two case-controlled studies described inappropriate therapy as an independent risk factor for mortality (3, 4). At our center (Hacettepe University School of Medicine Hospital, a 1,000-bed tertiary-care teaching hospital), we evaluated the factors that influenced the outcomes in patients with bacteremia caused by S. maltophilia. We retrospectively reviewed the reports of our clinical microbiology laboratory to identify the study patients during a six-year period from 1998 to 2004. Case patients were defined as those who were >16 years of age, had at least one blood culture positive for S. maltophilia, and had clinical signs of systemic infection. The mortality rate 30 days after the onset of bacteremia was used as the main outcome measure. Appropriate therapy was defined as one or more agents active against S. maltophilia, given adequate dose and route of administration, not later than 24 h after the blood culture was obtained. All statistical analyses were performed by using SPSS software (version 10.0; SPSS, Chicago, IL). Numerical data were reported (medians and interquartile ranges). To test for the differences between quantitative variables between appropriate and inappropriate therapies, independent-sample t tests were used for normally distributed variables. Differences between categorical variables were analyzed by the chi-square test with the continuity correction or the Fisher exact test where appropriate. Fifty-six patients with S. maltophilia bacteremia were identified. A total of 41 patients were included in the analysis. Fifteen cases whose medical records contained missing data were excluded from the study. The overall 30-day mortality rate was 31.7%. The patients who died within 30 days after the onset of S. maltophilia bacteremia had a longer duration of hospitalization and a higher rate of intensive care unit stay (at the time of initial bacteremia), as well as an increased need for mechanical ventilation and presentation with septic shock (Table ​(Table1).1). Twelve (29.2%) patients had received inappropriate therapy. Eight (66.7%) patients who were treated inappropriately died, compared to 5 (17.2%) of 29 who died though they received an appropriate antibiotic(s). Six of 8 (75.0%) patients who died were on carbapenems when S. maltophilia bacteremia developed. TABLE 1. Demographic characteristics of the patients with bloodstream infection caused by S. maltophilia In this limited study, we have shown a higher mortality rate for the bacteremic patients who did not receive appropriate therapy against S. maltophilia. We believe this issue should be further evaluated by case-controlled studies with a higher number of patients who had similar comorbid factors. In addition, the practicing physician should consider S. maltophilia as the causative organism in a patient who deteriorates under carbapenem therapy.

Attributable mortality of Stenotrophomonas maltophilia bacteremia.

A systematic evaluation of the attributable mortality of Stenotrophomonas maltophilia bacteremia was undertaken in a matched, retrospective, case-control study. We determined the attributable mortality rate (26.7%) and mortality risk ratio (an 8-fold increase) of S. maltophilia bacteremia. The attributable mortality rate for S. maltophilia bacteremia is similar to the attributable mortality rate for other nosocomial bloodstream infections.