Gram-negative bacterial infections in surgical intensive care unit patients following abdominal surgery: high mortality associated with Stenotrophomonas maltophilia infection

BACKGROUND

Stenotrophomonas maltophilia, a multidrug-resistant gram-negative bacteria (GNB), is an emerging nosocomial pathogen. This study assessed the clinical outcomes of GNB infections in surgical intensive care unit (SICU) patients post-abdominal surgery, focusing on the differences between S. maltophilia and other GNBs, including Pseudomonas aeruginosa.

METHODS

A retrospective study was conducted on SICU patients at Kaohsiung Chang Gung Memorial Hospital from 2010 to 2020, who developed GNB infections following abdominal surgery.

RESULTS

Of 442 patients, 237 had S. maltophilia and 205 had non-S. maltophilia GNB infections (including 81 with P. aeruginosa). The overall mortality rate was 44.5%, and S. maltophilia infection emerged as a significant contributor to the mortality rate in patients with GNB infections. S. maltophilia patients had longer mechanical ventilation and SICU stays, with a 30-day mortality rate of 35.4%, higher than the non-S. maltophilia GNB (22.9%) and P. aeruginosa (21%) groups. In-hospital mortality was also higher in the S. maltophilia group (53.2%) compared to the non-S. maltophilia GNB (34.6%) and P. aeruginosa groups (29.6%). Risk factors for acquiring S. maltophilia included a higher Sequential Organ Failure Assessment score and prior broad-spectrum antibiotics use. Older age, polymicrobial infections, and elevated bilirubin were associated with increased 30-day mortality in S. maltophilia patients.

CONCLUSION

S. maltophilia infections in post-abdominal surgery patients are linked to higher mortality than non-S. maltophilia GNB and P. aeruginosa infections, emphasizing the need for early diagnosis and treatment to improve outcomes.

Risk factors for mortality in Stenotrophomonas maltophilia bacteremia - a meta-analysis

BACKGROUND

Stenotrophomonas maltophilia (S. maltophilia) is a nosocomial pathogen causing life-threatening invasive infections with a high mortality rate in some patient populations, especially those who are severely ill or immunocompromised. There is a need for data on mortality in patients with S. maltophilia bacteremia.

OBJECTIVE

In this meta-analysis, we aimed to investigate risk factors for mortality in S. maltophilia bacteremia.

METHODS

Studies comparing patients who died from S. maltophilia bacteremia with patients who survived were considered for inclusion. Studies were included if they reported one or more risk factors for mortality. Mortality risk factors included clinical predisposing factors, predisposing comorbidities and appropriateness of antibiotic therapy.

RESULTS

Nineteen studies with 1248 patients were included in the meta-analysis. Five hundred and six (40.5%) patients died. The following risk factors for mortality were identified: ICU admission, septic shock, need for mechanical ventilation, indwelling central venous catheter, neutropenia, comorbid hematological malignancies, chronic kidney disease, inappropriate antimicrobial therapy and prior antibiotic use.

CONCLUSIONS

Appropriate antimicrobial therapy had a protective effect against mortality in S. maltophilia bacteremia. Indwelling central venous catheter, neutropenia, hematological malignancies and chronic kidney disease were also risk factors for mortality.

Global mapping of antibiotic resistance rates among clinical isolates of Stenotrophomonas maltophilia: a systematic review and meta-analysis

INTRODUCTION

Infections caused by Stenotrophomonas maltophilia are clinically important due to its intrinsic resistance to a broad range of antibiotics. Therefore, selecting the most appropriate antibiotic to treat S. maltophilia infection is a major challenge.

AIM

The current meta-analysis aimed to investigate the global prevalence of antibiotic resistance among S. maltophilia isolates to the develop more effective therapeutic strategies.

METHOD

A systematic literature search was performed using the appropriate search syntax after searching Pubmed, Embase, Web of Science and Scopus databases (May 2023). Statistical analysis was performed using Pooled and the random effects model in R and the metafor package. A total of 11,438 articles were retrieved. After a thorough evaluation, 289 studies were finally eligible for inclusion in this systematic review and meta-analysis.

RESULT

Present analysis indicated that the highest incidences of resistance were associated with doripenem (97%), cefoxitin (96%), imipenem and cefuroxime (95%), ampicillin (94%), ceftriaxone (92%), aztreonam (91%) and meropenem (90%) which resistance to Carbapenems is intrinsic. The lowest resistance rates were documented for minocycline (3%), cefiderocol (4%). The global resistance rate to TMP-SMX remained constant in two periods before and after 2010 (14.4% vs. 14.6%). A significant increase in resistance to tigecycline and ceftolozane/tazobactam was observed before and after 2010.

CONCLUSIONS

Minocycline and cefiderocol can be considered the preferred treatment options due to low resistance rates, although regional differences in resistance rates to other antibiotics should be considered. The low global prevalence of resistance to TMP-SMX as a first-line treatment for S. maltophilia suggests that it remains an effective treatment option.

Global prevalence and distribution of antibiotic resistance among clinical isolates of Stenotrophomonas maltophilia: A systematic review and meta-analysis

OBJECTIVES

Stenotrophomonas maltophilia (S. maltophilia), an opportunistic pathogen, causes infection in patients undergoing immunosuppressive therapy, mechanical ventilation, or catheters and in long-term hospitalized patients. Due to its extensive resistance to various antibiotics and chemotherapeutic agents, S. maltophilia is challenging to treat. Using case reports, case series, and prevalence studies, the current study provides a systematic review and meta-analysis of antibiotic resistance profiles across clinical isolates of S. maltophilia.

METHODS

A systematic literature search was performed for original research articles published in Medline, Web of Science, and Embase databases from 2000 to 2022. Statistical analysis was performed using STATA 14 software to report antibiotic resistance of S. maltophilia clinical isolates worldwide.

RESULTS

223 studies (39 case reports/case series and 184 prevalence studies) were collected for analysis. A meta-analysis of prevalence studies demonstrated that the most antibiotic resistance worldwide was to levofloxacin, trimethoprim-sulfamethoxazole (TMP/SMX), and minocycline (14.4%, 9.2%, and 1.4%, respectively). Resistance to TMP/SMX (36.84%), levofloxacin (19.29%), and minocycline (1.75%) were the most prevalent antibiotic resistance types found in evaluated case reports/case series studies. The highest resistance rate to TMP/SMX was reported in Asia (19.29%), Europe (10.52%), and America (7.01%), respectively.

CONCLUSION

Considering the high resistance to TMP/SMX, more attention should be paid to patients' drug regimens to prevent the emergence of multidrug-resistant S. maltophilia isolates.

Global prevalence and antibiotic resistance in clinical isolates of Stenotrophomonas maltophilia: a systematic review and meta-analysis

Introduction

Stenotrophomonas maltophilia is a little-known environmental opportunistic bacterium that can cause broad-spectrum infections. Despite the importance of this bacterium as an emerging drug-resistant opportunistic pathogen, a comprehensive analysis of its prevalence and resistance to antibiotics has not yet been conducted.

Methods

A systematic search was performed using four electronic databases (MEDLINE via PubMed, Embase, Scopus, and Web of Science) up to October 2019. Out of 6,770 records, 179 were documented in the current meta-analysis according to our inclusion and exclusion criteria, and 95 studies were enrolled in the meta-analysis.

Results

Present analysis revealed that the global pooled prevalence of S. maltophilia was 5.3 % [95% CI, 4.1-6.7%], with a higher prevalence in the Western Pacific Region [10.5%; 95% CI, 5.7-18.6%] and a lower prevalence in the American regions [4.3%; 95% CI, 3.2-5.7%]. Based on our meta-analysis, the highest antibiotic resistance rate was against cefuroxime [99.1%; 95% CI, 97.3-99.7%], while the lowest resistance was correlated with minocycline [4·8%; 95% CI, 2.6-8.8%].

Discussion

The results of this study indicated that the prevalence of S. maltophilia infections has been increasing over time. A comparison of the antibiotic resistance of S. maltophilia before and after 2010 suggested there was an increasing trend in the resistance to some antibiotics, such as tigecycline and ticarcillin-clavulanic acid. However, trimethoprim-sulfamethoxazole is still considered an effective antibiotic for treating S. maltophilia infections.

Appropriate antibiotic therapy is a predictor of outcome in patients with Stenotrophomonas maltophilia blood stream infection in the intensive care unit

BACKGROUND/PURPOSE

The study was to assess the relationship between antibiotic therapy and the outcome in intensive care unit (ICU) patients with Stenotrophomonas maltophilia bloodstream infection (BSI).

METHODS

ICU patients with monomicrobial S. maltophilia BSI from January 2004 to December 2019 were included and divided into two groups-those with- and without appropriate antibiotic therapy after BSI-for comparison. The primary outcome was the relationship between appropriate antibiotic therapy and 14-day mortality. The secondary outcome was the influence of different antibiotic therapies: levofloxacin- and trimethoprim-sulfamethoxazole (TMP/SMX)-containing regimens, on 14-day mortality.

RESULTS

A total of 214 ICU patients were included. Patients received appropriate antibiotic therapy (n = 133) after BSI had a lower 14-day mortality than those (n = 81) without appropriate antibiotic therapy (10.5% vs. 46.9%, p < 0.001). No difference on 14-day mortality between groups of patients by time of appropriate antibiotic therapy was observed (p > 0.05). After a propensity score matching, the results is consistent that 14-day mortality were lower in patients with appropriate antibiotic therapy than those without appropriate antibiotic therapy (11.5% vs. 39.3%, p < 0.001). Among patients with S. maltophilia BSI receiving appropriate antibiotic therapy, there was a trend levofloxacin-containing regimens is associated with lower mortality than TMP/SMX-containing regimens (HR 0.233, 95% CI 0.050-1.084, p = 0.063).

CONCLUSION

Appropriate antibiotic therapy was associated with decreased 14-day mortality in ICU patients with S. maltophilia BSI regardless of time. Levofloxacin-containing regimens may be better choice than TMP/SMX -containing regimens in treating ICU patients with S. maltophilia BSI.

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

Introduction

Stenotrophomonas 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 Methods

We retrospectively evaluated antimicrobial treatment in adult patients with nosocomial SM bacteraemia, with the 14th and 30th-day mortality as the outcome.

Results

In 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.

Dengue co-infection in a blood stream infection caused by Stenotrophomonas maltophilia: A case report

Stenotrophomonas maltophilia (S. maltophilia) is an emerging opportunistic bacterial pathogen with resistance to several commonly used antibiotics. Owing to its multidrug resistance (MDR), management of S. maltophilia blood stream infection (BSI) is challenging and requires the selection of appropriate antibiotic therapy. The presence of thrombocytopenia and shock are independent risk factors associated with increased mortality in patients with S. maltophilia BSI. We describe an unusual case of S. maltophilia BSI in a middle-age female complicated by dengue fever. We highlight the importance of early recognition of both dengue and S. maltophilia infection in management of such cases.

Risk factors and outcomes of Stenotrophomonas maltophilia bacteraemia: a comparison with bacteraemia caused by Pseudomonas aeruginosa and Acinetobacter species

Stenotrophomonas maltophilia (SM) is an important nosocomial pathogen that exhibits intrinsic resistance to various antimicrobial agents. However, the risk factors for SM bacteraemia have not been sufficiently evaluated. From January 2005 to September 2012, we retrospectively compared the clinical backgrounds and outcomes of SM bacteraemic patients (SM group) with those of bacteraemic patients due to Pseudomonas aeruginosa (PA group) or Acinetobacter species (AC group). DNA genotyping of the SM isolates using the Diversilab system was performed to investigate the genetic relationships among the isolates. The SM, PA, and AC groups included 54, 167, and 69 patients, respectively. Nine of 17 patients in the SM group receiving trimethoprim-sulfamethoxazole prophylaxis developed SM bacteraemia. Independent risk factors for SM bacteraemia were the use of carbapenems and antipseudomonal cephalosporins and SM isolation within 30 days prior to the onset of bacteraemia. Earlier SM isolation was observed in 32 of 48 patients (66.7%) with SM bacteraemia who underwent clinical microbiological examinations. Of these 32 patients, 15 patients (46.9%) had the same focus of bacteraemia as was found in the previous isolation site. The 30-day all-cause mortality rate among the SM group (33.3%) was higher than that of the PA group (21.5%, p = 0.080) and the AC group (17.3%, p = 0.041). The independent factor that was associated with 30-day mortality was the SOFA score. DNA genotyping of SM isolates and epidemiological data suggested that no outbreak had occurred. SM bacteraemia was associated with high mortality and should be considered in patients with recent use of broad-spectrum antibiotics or in patients with recent isolation of the organism.

Stenotrophomonas maltophilia infection during allogeneic hematopoietic stem cell transplantation: a single-center experience

To examine risk factors for Stenotrophomonas maltophilia (S. maltophilia) infection during allogeneic hematopoietic stem cell transplantation (allo-HSCT), we retrospectively analyzed 259 patients who underwent allo-HSCT. Not only S. maltophilia infection but also S. maltophilia colonization was associated with mortality during allo-HSCT. Among 52 episodes in 39 patients in whom S. maltophilia was detected, documented infection developed in 33 episodes (25 patients). The onset of S. maltophilia infection in the period from the conditioning regimen to engraftment was associated with a high mortality rate. Breakthrough S. maltophilia infection developed in 24% of the patients during prophylactic administration of fluoroquinolones, to which S. maltophilia is sensitive. Reinsertion of a central venous catheter (CVC) immediately after removal was suggested to be a risk for persistent S. maltophilia infection in the period of neutropenia. Our results indicated that (i) onset of S. maltophilia infection in the period from the conditioning therapy to engraftment and (ii) removal and immediate reinsertion of a CVC as treatment after the onset of S. maltophilia infection are possible risk factors for S. maltophilia-related mortality during allo-HSCT.

Minimal Inhibitory Concentration of Ceftazidime and Co-trimoxazole for Stenotrophomonas Maltophilia using E-test

Background

Stenotrophomonas maltophilia, previously named as Pseudomonas or Xanthomonas maltophilia, is an important nosocomial pathogen

Aim

The purpose of the present study was to investigate the prevalence of S. maltophilia in Iranian hospitals and its susceptibility to available antimicrobial agents.

Setting and design:

A cross-sectional study in Imam Khomeini Hospital affiliated to Tehran University of Medical Sciences.

Materials and Methods

All blood specimens were sent to the laboratory for blood culture and biochemical analysis. One hundred samples were positive for S. maltophilia. We used disk diffusion and E-test in order to determine minimal inhibitory concentration (MIC) of ceftazidime and co-trimoxazole as the first line antibiotics for S. maltophilia. The tests were performed and interpreted according to the guidelines of Clinical Laboratory Standards Institute (CLSI).

Statistical analysis:

Chi-square test and Kappa measurement of agreement were applied as appropriate.

Results

S. maltophilia was the most frequent pathogen (895 specimens; 38.9%) isolated from the samples which were mostly from emergency ward (780 specimens; 33.9%). Ceftazidime MIC₅₀ and MIC₉₀ were 2 and 32 μg/ml, respectively (sensitive ≤8 μg/ml and resistant ≥32 μg/ml according to CLSI guideline). MIC₅₀ and MIC₉₀ for co-trimoxazole were 0.5 and 2 μg/ml, respectively (sensitive ≤2 μg/ml and resistant ≥4 μg/ml according to CLSI guideline).

Conclusion

S. maltophilia is the most frequent pathogen in our hospital with a high susceptibility to both ceftazidime and co-trimoxazole.

Stenotrophomonas maltophilia: an emerging opportunist human pathogen

Stenotrophomonas maltophilia has emerged as an important opportunistic pathogen in the debilitated host. S maltophilia is not an inherently virulent pathogen, but its ability to colonise respiratory-tract epithelial cells and surfaces of medical devices makes it a ready coloniser of hospitalised patients. S maltophilia can cause blood-stream infections and pneumonia with considerable morbidity in immunosuppressed patients. Management of infection is hampered by high-level intrinsic resistance to many antibiotic classes and the increasing occurrence of acquired resistance to the first-line drug co-trimoxazole. Prevention of acquisition and infection depends upon the application of modern infection-control practices, with emphasis on the control of antibiotic use and environmental reservoirs.