Stenotrophomonas maltophilia-Associated Dacryocystitis in Leukemia-Infiltrated Lacrimal Sacs: Case and Review of Literature

A 91-year-old female with a history of chronic lymphocytic leukemia developed recurrent bouts of bilateral dacryocystitis. She underwent incision and drainage of the lacrimal sac with culture demonstrating the rare bacteria Stenotrophomonas maltophilia. She underwent subsequent dacryocystectomy with biopsy revealing bilateral involvement of chronic lymphocytic leukemia in the lacrimal sac. Stenotrophomonas maltophilia has been associated with immune suppression and is rarely seen in dacryocystitis. Local and/or systemic immune deregulation or suppression may play a role in lacrimal sac infection with this bacterium in some patients.

Optimization of Aztreonam in Combination With Ceftazidime/Avibactam in a Cystic Fibrosis Patient With Chronic Stenotrophomonas maltophilia Pneumonia Using Therapeutic Drug Monitoring: A Case Study

ABSTRACT

In this clinician-therapeutic drug monitoring (TDM) consultant interaction, the authors describe the use of TDM in an 11-year-old female patient with cystic fibrosis receiving ceftazidime/avibactam and aztreonam for the treatment of persistent pulmonary exacerbations caused by Stenotrophomonas pneumonia. Serum drug concentrations at a steady state confirmed inadequate antimicrobial exposure, and continuous infusions of both ceftazidime/avibactam and aztreonam were required to optimize the percentage of time when free drug remained above the minimum inhibitory concentration (MIC), known as fT > MIC. After dose adjustment, this continuous infusion strategy resulted in 100% target attainment for fT > MIC. This case illustrates the importance of TDM, and the logistical issues encountered with the use of alternative dosing strategies in pediatric patients with CF.

Removal of nitrogen from wastewater of date processing industries using a Saudi Arabian mesophilic bacterium, Stenotrophomonas maltophilia Al-Dhabi-17 in sequencing batch reactor

The main aim of the present study was to assess the technical feasibility of nutrients removal from the wastewater from the date processing industries in sequencing batch reactor. Heterotrophic nitrifying and aerobic denitrifying bacteria were isolated from the soil sediment samples. The bacterial strain Al-Dhabi-17 effectively removed nutrients than other isolates from the wastewater and characterized as Stenotrophomonas maltophilia Al-Dhabi-17. The nutrient removal efficacy was improved by optimizing process parameters. Removal of NH₄⁺ from the medium reached 42% within 60 h of cultivation and the nitrification rate was 111 ± 3.1 mg after 24 h. After 96 h, NO₃^- reached 6 ± 0.4 mg/mL concentration. The strain S. maltophilia Al-Dhabi-17 showed the ability to utilize NH₄⁺ ranged between 100 and 300 mg/L. The supplemented sucrose, glucose and date molasses reached maximum nitrification process after 72 h (p < 0.05). Reduction of NH₄⁺ -N reached 73.4% within 48 h time in the medium supplemented with date molasses. Nutrient removal was observed in the broad pH range (6.0-8.5) and maximum nutrient removal achieved at alkaline range (p < 0.05). Sequencing batch reactor was fed with wastewater and nutrient removal was analyzed under optimized condition. The associated chemical oxygen demand, phosphate and total nitrogen removal efficiencies for the suspended growth sequencing batch reactor were 96.5%, 97.9% and 88.4%, respectively. The sequencing batch reactor inoculated with S. maltophilia Al-Dhabi-17 showed promising for nitrogen removal.

In Vitro Activity and In Vivo Efficacy of Cefiderocol against Stenotrophomonas maltophilia

Cefiderocol is a novel siderophore cephalosporin antibiotic with broad coverage against difficult-to-treat Gram-negative bacteria, including those resistant to carbapenems. Its activity against Stenotrophomonas maltophilia was investigated in vitro against clinical isolates and in lung infection models using strains either resistant (SR202006) or susceptible (SR201934, SR200614) to trimethoprim-sulfamethoxazole. Cefiderocol demonstrated potent in vitro activity against all 217 S. maltophilia clinical isolates tested (MIC50, 0.063 μg/ml; MIC90, 0.25 μg/ml). Cefiderocol also demonstrated low MICs against the trimethoprim-sulfamethoxazole-resistant S. maltophilia strains (i.e., SR202006; MIC, 0.125 μg/ml). In a neutropenic mouse lung infection model, cefiderocol (30 mg/kg body weight and 100 mg/kg) demonstrated a significant, dose-dependent reduction in the lung viable bacteria cell count compared with untreated controls in S. maltophilia infection and was the only antibiotic tested to show a similar significant effect in a trimethoprim-sulfamethoxazole-resistant S. maltophilia infection. In immunocompetent rat lung infection models of S. maltophilia, humanized dosing of cefiderocol (2 g every 8 h) and meropenem (1 g every 8 h) revealed pharmacokinetic profiles similar to those in human subjects, and the humanized cefiderocol dosing significantly reduced the lung viable bacteria cell count compared with baseline controls, which received no intervention. Together, the results from these studies suggest that cefiderocol could provide an effective alternative treatment option for S. maltophilia infections in the lower respiratory tract, particularly strains resistant to empirical antibiotics, such as trimethoprim-sulfamethoxazole or minocycline.

Role of Stenotrophomonas maltophilia isolation in patients with non-CF bronchiectasis

INTRODUCTION

Stenotrophomonas maltophilia is a bacteria whose role in patients with cystic fibrosis (CF) bronchiectasis has been previously studied; little is known about its role in non-CF bronchiectasis.

MATERIALS AND METHODS

Aim of our study is to investigate the risk factors for S. maltophilia acquisition and its clinical impact on bronchiectasis patients. A retrospective observational cohort study enrolling patients attending the Bronchiectasis Clinic at the Royal Infirmary of Edinburgh, Scotland, UK. A total of 167 bronchiectasis patients undergoing intravenous (IV) antibiotic therapy were selected and divided according to single or chronic S. maltophilia isolation in sputum. The risk factors and prognostic impact were studied.

RESULTS

Single isolation was independently associated with lower baseline % predicted forced expiratory volume in 1 s [odds ratio (OR) 0.98; 95% confidence interval (CI) 0.970-1.044; P = 0.025] and with less radiological involvement (OR 0.379; 95% CI 0.175-0.819; P = 0.01). Chronic isolation was associated with the number of IV antibiotic courses in the year before and after the first isolation (OR 1.2; 95% CI 1.053-1.398; P = 0.007) and with the absence of Pseudomonas aeruginosa colonization (OR 0.207; 95% CI 0.056-0.764; P = 0.02). In the chronic isolation group, there were more exacerbations and more need of IV antibiotics in the year after the first isolation.

CONCLUSIONS

Poor lung function is the main independent risk factor for single isolation of S. maltophilia. For chronic colonization, the main independent risk factor is the number of IV antibiotic courses and the absence of P. aeruginosa chronic colonization. Only when chronically present, S. maltophilia had a clinical impact with more exacerbations.

Insights for the Growth of Stenotrophomonas maltophilia in a Diabetic Patient with Long-Term Antibiotic Use: A Case Study

BACKGROUND

Stenotrophomonas maltophilia is an uncommon gram-negative bacterium often found in individuals with long-standing broad-spectrum antibiotic use or catheter use; individuals undergoing hemodialysis; and individuals with prolonged respiratory disease, specifically, cystic fibrosis. To our knowledge, there are few reported cases of S maltophilia being the causative pathogen of infection in a diabetic foot wound.

METHODS

Following multiple surgical procedures and deep tissue cultures, S maltophilia was determined to be a secondary opportunistic colonizer of the wound, necessitating a change in antibiotic therapy.

RESULTS

The cultured pathogen was sensitive to ceftazidime, levofloxacin, and trimethoprim-sulfamethoxazole. The treatment team chose to use ceftazidime, as it also provided antibiotic coverage for the initial wound and blood cultures. Change in antibiotic therapy was initiated following multiple surgical procedures and angioplasty of the lower limb. The patient was discharged with a peripheral intravenous central catheter for outpatient antibiotic therapy.

CONCLUSIONS

Prolonged exposure to broad-spectrum antibiotics in individuals with multiple comorbidities including diabetes mellitus provides an advantageous environment for growth of uncommon multidrug-resistant organisms. Stenotrophomonas maltophilia may complicate the treatment of diabetic foot infections as an opportunistic pathogen. Understanding the implication of long-term broad-spectrum antibiotic treatment in the diabetic patient is important in managing postoperative complications and determining the correct course of treatment. The emergence of atypical pathogens in diabetic wounds must be managed appropriately.

Activity of Cefiderocol Alone and in Combination with Levofloxacin, Minocycline, Polymyxin B, or Trimethoprim-Sulfamethoxazole against Multidrug-Resistant Stenotrophomonas maltophilia

The production of an L1 metallo-β-lactamase and an L2 serine active-site β-lactamase precludes the use of β-lactams for the treatment of Stenotrophomonas maltophilia infections. Preclinical data suggest that cefiderocol is the first approved β-lactam with reliable activity against S. maltophilia, but data on strains resistant to current first-line agents are limited, and no studies have assessed cefiderocol-based combinations. The objective of this study was to evaluate and compare the in vitro activity of cefiderocol alone and in combination with levofloxacin, minocycline, polymyxin B, or trimethoprim-sulfamethoxazole (TMP-SMZ) against a collection of highly resistant clinical S. maltophilia isolates. For this purpose, the MICs of cefiderocol, ceftazidime, levofloxacin, minocycline, polymyxin B, and TMP-SMZ for 37 S. maltophilia isolates not susceptible to levofloxacin and/or TMP-SMZ were determined. Nine strains with various cefiderocol MICs were then tested in time-kill experiments with cefiderocol alone and in combination with comparators. The only agents for which susceptibility rates exceeded 40% were cefiderocol (100%) and minocycline (97.3%). Cefiderocol displayed the lowest MIC50 and MIC90 values (0.125 and 0.5 mg/liter, respectively). In time-kill experiments, synergy was observed when cefiderocol was combined with levofloxacin, minocycline, polymyxin B, or TMP-SMZ against 4/9 (44.4%), 6/9 (66.7%), 5/9 (55.5%), and 6/9 (66.7%) isolates, respectively. These data suggest that cefiderocol displays potent in vitro activity against S. maltophilia, including strains resistant to currently preferred agents. Future dynamic and in vivo studies of cefiderocol alone and in combination are warranted to further define cefiderocol's synergistic capabilities and its place in therapy for S. maltophilia infections.

Renal Transplant Recipient with Concurrent COVID-19 and Stenotrophomonas maltophilia Pneumonia Treated with Trimethoprim/Sulfamethoxazole Leading to Acute Kidney Injury: A Therapeutic Dilemma

BACKGROUND Although coronavirus disease 2019 (COVID-19) manifests primarily as a lung infection, its involvement in acute kidney injury (AKI) is gaining recognition and is associated with increased morbidity and mortality. Concurrent infection, which may require administration of a potentially nephrotoxic agent, can worsen AKI and lead to poor outcomes. Stenotrophomonas maltophilia is a multidrug-resistant gram-negative bacillus associated with nosocomial infections, especially in severely immunocompromised and debilitated patients. Trimethoprim/sulfamethoxazole combination (TMP/SMX) is considered the treatment of choice but can itself lead to AKI, posing a significant challenge in the management of patients with concomitant COVID-19 and S. maltophilia pneumonia. CASE REPORT A 64-year-old male with end-stage renal disease and post renal transplant presented with severe respiratory symptoms of COVID-19 and was intubated upon admission. His renal functions were normal at the time of admission. The patient subsequently developed superimposed bacterial pneumonia with S. maltophilia requiring administration of TMP/SMX. However, TMP/SMX led to the development of AKI, which continued to worsen despite appropriate management including hemodialysis. This coincided with and most likely resulted in the patient's clinical deterioration and ultimate death. CONCLUSIONS The etiology of kidney disease involvement in patients with COVID-19 is still evolving and appears to be multifactorial. The condition can significantly worsen especially when nephrotoxic agents are given, probably due to a cumulative or synergistic effect. Great caution should be taken when administering nephrotoxic agents in the setting of COVID-19 as it can lead to adverse patient outcomes.

Degradation kinetics of carbendazim by Klebsiella oxytoca, Flavobacterium johnsoniae, and Stenotrophomonas maltophilia strains

The fungicide carbendazim is an ecotoxic pollutant frequently found in water reservoirs. The ability of microorganisms to remove pollutants found in diverse environments, soil, water, or air is well documented. Although microbial communities have many advantages in bioremediation processes, in many cases, those with the desired capabilities may be slow-growing or have low pollutant degradation rates. In these cases, the manipulation of the microbial community through enrichment with specialized microbial strains showing high specific growth rates and high rates and efficiencies of pollutant degradation is desirable. In this work, bacteria of the genera Klebsiella, Flavobacterium, and Stenotrophomonas, isolated from the biofilm attached to the packed zones of a biofilm reactor, were able to grow individually in selective medium containing carbendazim. In the three bacteria studied, the mheI gene encoding the first enzyme involved in the degradation of the fungicide carbendazim was found. Studying the dynamics of growth and carbendazim degradation of the three bacteria, the effect of co-formulants was also evaluated. The pure compound and a commercial formulation of carbendazim were used as substrates. Finally, the study made it possible to define the biokinetic advantages of these strains for amendment of microbial communities.

Activity of cefiderocol against high-risk clones of multidrug-resistant Enterobacterales, Acinetobacter baumannii, Pseudomonas aeruginosa and Stenotrophomonas maltophilia

BACKGROUND

Cefiderocol is a novel siderophore cephalosporin, developed for activity against MDR Gram-negative bacilli (MDR-GNB).

OBJECTIVES

To assess the in vitro antibacterial activity of cefiderocol against a collection of MDR-GNB clinical isolates from hospitals in southern Spain.

METHODS

Two hundred and thirty-one isolates of successful clones were tested: 125 Enterobacterales (121 ESBL- and/or carbapenemase-producing Klebsiella pneumoniae and 4 carbapenemase-producing Enterobacter cloacae), 80 Acinetobacter baumannii, 6 Pseudomonas aeruginosa and 20 Stenotrophomonas maltophilia. Ceftolozane/tazobactam, ceftazidime, ceftazidime/avibactam, cefepime, aztreonam, meropenem, amikacin, ciprofloxacin, colistin and tigecycline were used as comparators against Enterobacterales, P. aeruginosa and A. baumannii. Minocycline, levofloxacin and trimethoprim/sulfamethoxazole were studied against S. maltophilia instead of aztreonam, ciprofloxacin and cefepime. MICs were determined by broth microdilution according to CLSI guidelines. MIC determination was performed in CAMHB for all antimicrobials except cefiderocol, where iron-depleted CAMHB was used.

RESULTS

Cefiderocol showed potent in vitro activity against the isolates analysed. MIC50 and MIC90 values were in the ranges 0.125-8 mg/L and 0.5-8 mg/L, respectively, and 98% of isolates were inhibited at ≤4 mg/L. Only five isolates showed cefiderocol MICs of >4 mg/L: three ST2/OXA-24/40-producing A. baumannii, one ST114/VIM-1-producing E. cloacae and one ST114/VIM-1 + OXA-48-producing E. cloacae. All KPC-3-producing K. pneumoniae were susceptible to cefiderocol, even those resistant to ceftazidime/avibactam. P. aeruginosa isolates showed cefiderocol MICs of <4 mg/L, including those resistant to ceftolozane/tazobactam. S. maltophilia isolates displayed cefiderocol MICs of <4 mg/L, including those resistant to levofloxacin and/or trimethoprim/sulfamethoxazole.

CONCLUSIONS

Cefiderocol showed excellent activity against MDR-GNB, including carbapenem-resistant isolates, and was the most active antimicrobial tested against this collection.

Antibiotic treatment for Stenotrophomonas maltophilia in people with cystic fibrosis

BACKGROUND

Stenotrophomonas maltophilia is one of the most common emerging multi-drug resistant organisms found in the lungs of people with cystic fibrosis and its prevalence is increasing. Chronic infection with Stenotrophomonas maltophilia has recently been shown to be an independent predictor of pulmonary exacerbation requiring hospitalization and antibiotics. However, the role of antibiotic treatment of Stenotrophomonas maltophilia infection in people with cystic fibrosis is still unclear. This is an update of a previously published review.

OBJECTIVES

The objective of our review is to assess the effectiveness of antibiotic treatment for Stenotrophomonas maltophilia in people with cystic fibrosis. The primary objective is to assess this in relation to lung function and pulmonary exacerbations in the setting of acute pulmonary exacerbations. The secondary objective is to assess this in relation to the eradication of Stenotrophomonas maltophilia.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. We also searched a registry of ongoing trials and the reference lists of relevant articles and reviews. Date of latest search: 03 March 2020.

SELECTION CRITERIA

Randomized controlled trials of Stenotrophomonas maltophilia mono-infection or Stenotrophomonas maltophilia co-infection with Pseudomonas aeruginosa in either the setting of an acute pulmonary exacerbation or a chronic infection treated with suppressive antibiotic therapy.

DATA COLLECTION AND ANALYSIS

Both authors independently assessed the trials identified by the search for potential inclusion in the review.

MAIN RESULTS

We identified only one trial of antibiotic treatment of pulmonary exacerbations that included people with cystic fibrosis with Stenotrophomonas maltophilia. However, this trial had to be excluded because data was not available per pathogen.

AUTHORS' CONCLUSIONS

This review did not identify any evidence regarding the effectiveness of antibiotic treatment for Stenotrophomonas maltophilia in people with cystic fibrosis. Until such evidence becomes available, clinicians need to use their clinical judgement as to whether or not to treat Stenotrophomonas maltophilia infection in people with cystic fibrosis. Randomized clinical trials are needed to address these unanswered clinical questions.

Effect of copper-resistant Stenotrophomonas maltophilia on maize (Zea mays) growth, physiological properties, and copper accumulation: potential for phytoremediation into biofortification

In this study, Cu-tolerant PGP bacteria were isolated from the contaminated soils of Tapi (Surat, Gujarat, India). From a set of 118 bacteria isolated from the contaminated soil, the isolate RBTS7 was found to be efficient in tolerating 0.3 g (w/v) Cu. The isolate was identified as Stenotrophomonas maltophilia, based on biochemical and 16S rRNA gene sequencing. Further, the isolate was also found to produce indole acetic acid (140 µg/ml) and siderophore, and solubilize potassium. Inoculation study was carried out in the presence and absence of Cu in the greenhouse. The results revealed that S. maltophilia enhanced plant growth and biomasses compared to control. In addition to plant growth attributes, the isolate also enhanced chlorophyll a and b (434.1 and 496.7%) contents and antioxidant properties such as proline (168.2%), total phenolic compounds (33.5%), and ascorbic acid oxidase (62.3%) compared to control with Cu and without Cu. Inoculation of S. maltophilia + Cu enhanced the uptake of Cu in maize root (77.4%) and stem (112.0%) compared to Cu-stressed control. The results clearly indicated the inoculation of S. maltophilia reduced the toxicity of Cu and in turn enhanced the plant growth and mobilization of Cu to the plant parts.

Characteristics of Stenotrophomonas maltophilia infection in children in Sichuan, China, from 2010 to 2017

Stenotrophomonas maltophilia (S. maltophilia) is an important nosocomial bacterial pathogen. However, the clinical features of children with S. maltophilia infection, the predisposing factors, and the antibiotic susceptibility of the bacteria have not been fully evaluated.In this study, the data of children with S. maltophilia infection from the West China Second University Hospital of Sichuan University (Chengdu, China) between July 2010 and October 2017 were collected and analyzed. The clinical features of enrolled children, the predisposing factors, and the antibiotic susceptibility were reported.In total, infection of S. maltophilia was identified in 128 patients. Most of these patients were under 1 year old (67.2%) and were mainly diagnosed as pneumonia (69%). A large proportion had underlying diseases (45.3%), received immunosuppressive therapy (53.1%), had undergone invasive operations (41.4%), had a history of carbapenem antibiotics use within 7 days before culture acquisition (54.7%), history of intensive care unit (ICU) hospitalization within previous 30 days (34.4%), and other risk factors. In particular, invasive operation (95% confidence interval [CI]: 1.125-14.324, P = .032), especially mechanical ventilation (95% CI: 1.277-20.469, P = .021), and ICU admission (95% CI: 1.743-22.956, P = .005) were independent risk factors for the children to develop severe S. maltophilia infection. As for antibiotic susceptibility, trimethoprim sulfamethoxazole (TMP-SMX), piperacillin tazobactam, ticarcillin clavulanate, and ceftazidime exhibited strong antibacterial activities against S. maltophilia, the susceptibility rates were 97.5%, 86.7%, 92.9%, and 81.5%, respectively.We report the clinical features of children with S. maltophilia infection, the predisposing factors and the antibiotic susceptibility. TMP-SMX can continue to be the first choice for the treatment of S. maltophilia infection. Piperacillin tazobactam, ticarcillin clavulanate, and the third generation cephalosporins can be used as alternative drugs.

Carbon selection for nitrogen degradation pathway by Stenotrophomonas maltophilia: Based on the balances of nitrogen, carbon and electron

A novel strain DQ01 capable of simultaneous removal of nitrate and ammonium under the aerobic condition was isolated from the landfill leachate and identified as Stenotrophomonas maltophilia. The result showed that S. maltophilia had carbon selection for the nitrogen removal pathway, and preferred to utilize carboxylate rather than carbohydrate, as carboxylate could directly participate in TCA cycle without Embden Meyerhof Parmas (EMP). Nitrogen and carbon balances confirmed that the ammonium assimilation was the main or even sole removal pathway for S. maltophilia, and carboxylate was more conducive to heterotrophic nitrification-aerobic denitrification (HN-AD) process due to the serious self-alkalization and higher reduction potential of carboxylate, which followed: NH₄⁺ → NO₂^- → NO₃^- → NO₂^- → NO due to the lack of nor and nos. Meanwhile, the higher C/N and nitrate could generate a more powerful ion transport driving force to accelerate the electron transfer in the denitrifying respiratory chain.

The Synthesis and Characterization of PEG-SH-Modified Gold Nanoparticle in One-Pot Synthesis by Stenotrophomonas maltophilia

Colloidal gold nanoparticles have been researched and utilized in many technical applications. However, the conventionalmethods to produce polyethyleneglycol (PEG) immobilized gold nanoparticles have to take several steps, including residual solvent removing. In the study, we propose an idea green route to synthesize gold nanoparticles by using Stenotrophomonas maltophilia in a one-pot reaction. The relationship between Au precursor and S. maltophilia was evaluated systematically. After PEG-SH addition, the bacterial cell wall was broken down and the synthetic nanoparticles could be released into culture medium. Furthermore, we identified that the crystal structure of synthetic gold nanoparticle was face-center cubic and PEG-SH was immobilized on synthetic gold nanoparticle ideally. The size of Au-PEG-SH was smaller than 30 nm. These findings suggest that gold nanoparticle with PEG-SH modification could be prepared in an eco-friendly one-pot reaction through the metabolic activity of S. maltophilia.

Stenotrophomonas maltophilia AHL-Degrading Strains Isolated from Marine Invertebrate Microbiota Attenuate the Virulence of Pectobacterium carotovorum and Vibrio coralliilyticus

Many Gram-negative aquacultural and agricultural pathogens control virulence factor expression through a quorum-sensing (QS) mechanism involving the production of N-acylhomoserine (AHL) signalling molecules. Thus, the interruption of QS systems by the enzymatic degradation of signalling molecules, known as quorum quenching (QQ), has been proposed as a novel strategy to combat these infections. Given that the symbiotic bacteria of marine invertebrates are considered to be an important source of new bioactive molecules, this study explores the presence of AHL-degrading bacteria among 827 strains previously isolated from the microbiota of anemones and holothurians. Four of these strains (M3-1, M1-14, M3-13 and M9-54-2), belonging to the species Stenotrophomonas maltophilia, were selected on the basis of their ability to degrade a broad range of AHLs, and the enzymes involved in their activity were identified. Strain M9-54-2, which showed the strongest AHL-degrading activity, was selected for further study. High-performance liquid chromatography-mass-spectrometry confirmed that the QQ enzyme is not a lactonase. Strain M9-54-2 degraded AHL accumulation and reduced the production of enzymatic activity in Pectobacterium carotovorum CECT 225^T and Vibrio coralliilyticus VibC-Oc-193 in in vitro co-cultivation experiments. The effect of AHL inactivation was confirmed by a reduction in potato tuber maceration and brine shrimp (Artemia salina) mortality caused by P. carotovorum and Vibrio coralliilyticus, respectively. This study strengthens the evidence of marine organisms as an underexplored and promising source of QQ enzymes, useful to prevent infections in aquaculture and agriculture. To our knowledge, this is the first time that anemones and holothurians have been studied for this purpose.

Fatal Neutropenic Enterocolitis Caused by Stenotrophomonas maltophilia: A Rare and Underrecognized Entity

Although Stenotrophomonas maltophilia causes substantial morbidity and mortality in immunocompromised patients, it has not been described as a causal pathogen of neutropenic enterocolitis (NEC). We describe the first case of histologically-confirmed NEC caused by S. maltophilia accompanied by bacteremia and pneumonia after salvage chemotherapy for acute myeloid leukemia relapse following a second hematopoietic stem cell transplantation. S. maltophilia should be included as a pathogenic organism of NEC in severely immunocompromised patients to prevent a delayed diagnosis, which carries a high risk of inappropriate antimicrobial selection and fatal outcome.

Degradation of 4-chlorophenol and microbial diversity in soil inoculated with single Pseudomonas sp. CF600 and Stenotrophomonas maltophilia KB2

Soil contamination with chlorophenols is a serious problem all over the world due to their common use in different branches of industry and agriculture. The objective of this study was to determine whether bioaugmenting soil with single Pseudomonas sp. CF600 and Stenotrophomonas maltophilia KB2 and additional carbon sources such as phenol (P) and sodium benzoate (SB) could enhance the degradation of 4-chlorophenol (4-CP). During the degradation experiment, the number of bacteria as well as the structural and functional diversity of the soil microbial communities were determined. It was found that the most effective degradation of 4-CP in the soil was observed after it was inoculated with CF600 and the addition of SB. The biodegradation of five doses of 4-CP in this soil proceeded within 100 days. At the same time, the rate of the disappearance of 4-CP in the soil that had been bioaugmented with CF600 and contaminated with 4-CP and P was 5-6.5 times lower compared to its rate of disappearance in the soil that had been contaminated with 4-CP. The biodegradation of 4-CP in all of the treated and untreated soils was accompanied by a systematic decrease in the number of heterotrophic bacteria (THB) ranging between 13 and 40%. It was also proven that the tested aromatic compounds affected the soil microbial community structure through an increase in the marker fatty acids for Gram-negative bacteria (BG-) and fungi (F). The essential changes in the patterns of the fatty acid methyl esters (FAMEs) for the polluted soil included an increase in the fatty acid saturation and hydroxy fatty acid abundance. The obtained results also indicated that the introduction of CF600 into the soil contaminated with 4-CP and SB or P caused an increase in the functional diversity of the soil microorganisms. In contrast, in the soil that had been inoculated with KB2 and in the non-inoculated soil, the addition of 4-CP and P decreased the microbial activity. In conclusion, the inoculation of both strains into contaminated soil with aromatic compounds caused irreversible changes in the functional and structural diversity of the soil microbial communities.

Unusual case of rapid growing intraabdominal abscess caused by Stenotrophomonas maltophilia after laparoscopic appendectomy due to perforated appendicitis: A case report

INTRODUCTION

An intraabdominal abscess due to Stenotrophomonas maltophilia (S maltophilia) infection is a very rare clinical manifestation. S maltophilia is a glucose nonfermentative, aerobic, gram-negative, mobile, and biofilm-forming bacterium. It is an opportunistic pathogen and uncommon cause of infection. Respiratory tract infections (pneumonia) and bloodstream infections (bacteremia) are the most common clinical manifestations of S maltophilia infection.

CONCLUSIONS

This case report describes an unusual case of a rapidly growing, extremely large intraabdominal abscess (within 1 week during antibiotic therapy), which was detected 2 weeks after a laparoscopic appendectomy was performed for perforated appendicitis and was caused by multidrug-resistant S maltophilia infection.

A Case of Bacteremia Urinary Tract Infection Caused by Stenotrophomonas maltophilia in an 8-month-old Boy

Bacteremic urinary tract infection (UTI) caused by Stenotrophomonas maltophilia rarely occurs in pediatric patients. We report a case of bacteremic UTI caused by S. maltophilia in an 8-month-old boy with a congenital ureteropelvic junction obstruction on the left side. The patient was brought to our hospital with a chief complaint of fever. He had undergone a nephrostomy tube insertion 4 months previously, and the tube had been removed 2 weeks before presentation at our hospital. He had a white blood cell count of 6,100/μL and a serum C-reactive protein level of 4.51 mg/dL. A microscopic urinalysis and Gram stain showed numerous Gram-negative bacilli and many leukocytes, and an ultrasonography showed grade 4 hydronephrosis of the left kidney. Based on these findings, we diagnosed the infant as having a complex UTI and started the intravenous administration of piperacillin/tazobactam. After 2 days, a urine culture showed Gram-negative bacilli (107 CFU/mL). Gram-negative bacilli were also cultured from two blood samples that were taken from different vessels at the time of admission. The Gram-negative bacilli were identified as S. maltophilia via the automated bacterial identification system. The patient recovered after a 2-week intravenous piperacillin/tazobactam treatment and subsequent oral treatment with trimethoprim-sulfamethoxazole. Since medical devices are susceptible to contamination with S. maltophilia, we suspect that the nephrostomy tube was the most likely source of infection.

Antibiotic treatment for Stenotrophomonas maltophilia in people with cystic fibrosis

BACKGROUND

Stenotrophomonas maltophilia is one of the most common emerging multi-drug resistant organisms found in the lungs of people with cystic fibrosis and its prevalence is increasing. Chronic infection with Stenotrophomonas maltophilia has recently been shown to be an independent predictor of pulmonary exacerbation requiring hospitalization and antibiotics. However, the role of antibiotic treatment of Stenotrophomonas maltophilia infection in people with cystic fibrosis is still unclear. This is an update of a previously published review.

OBJECTIVES

The objective of our review is to assess the effectiveness of antibiotic treatment for Stenotrophomonas maltophilia in people with cystic fibrosis. The primary objective is to assess this in relation to lung function and pulmonary exacerbations in the setting of acute pulmonary exacerbations. The secondary objective is to assess this in relation to the eradication of Stenotrophomonas maltophilia.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. We also searched a registry of ongoing trials and the reference lists of relevant articles and reviews.Date of latest search: 27 May 2016.

SELECTION CRITERIA

Any randomized controlled trial of Stenotrophomonas maltophilia mono-infection or Stenotrophomonas maltophilia co-infection with Pseudomonas aeruginosa in either the setting of an acute pulmonary exacerbation or a chronic infection treated with suppressive antibiotic therapy.

DATA COLLECTION AND ANALYSIS

Both authors independently assessed the trials identified by the search for potential inclusion in the review.

MAIN RESULTS

The initial search strategy identified only one trial of antibiotic treatment of pulmonary exacerbations that included people with cystic fibrosis with Stenotrophomonas maltophilia. However, this trial had to be excluded because data was not available per pathogen.

AUTHORS' CONCLUSIONS

This review did not identify any evidence regarding the effectiveness of antibiotic treatment for Stenotrophomonas maltophilia in people with cystic fibrosis. Until such evidence becomes available, clinicians need to use their clinical judgement as to whether or not to treat Stenotrophomonas maltophilia infection in people with cystic fibrosis. Randomized clinical trials are needed to address these unanswered clinical questions.

[Stenotrophomonas maltophilia as the cause of ventilator-associated pneumonia in a female patient with toxic epidermal necrolysis and Clostridium colitis: time for off-label tigecycline?]

Toxic epidermal necrolysis (TEN) is an autoimmune disease which is usually caused by a reaction to drugs. It affects mainly the skin and mucous membranes. It is a rare condition with a high mortality rate. Fatal outcomes in patients with TEN are mostly due to infectious complications. As antimicrobial drugs may induce this syndrome, the management of this condition is very complicated. Tigecycline is still a relatively new antibiotic approved in Europe for use in complicated intra-abdominal infections and complicated skin and soft tissue infections. Among major advantages of tigecycline in patients with TEN are its good penetrability into tissues, wide spectrum of activity that makes it suitable for use as monotherapy, and last but not least, in comparison with other antimicrobials, a very low potential for exacerbation of the severity of the underlying disease by further stimulation of the immune system. A case report is presented of a successful management of an 81-year-old woman with TEN and multiple infectious complications in different anatomic locations, the most serious of which was ventilator-associated pneumonia caused by Stenotrophomonas maltophilia. Her general condition was further aggravated by Clostridium colitis. Tigecycline was used as the therapeutic option for ventilator-associated pneumonia, although prescribed off-label.Key words: toxic epidermal necrolysis - tigecycline - off-label indications - Clostridium colitis.

[Orbital cellulitis with concomitant bacteraemia (Stenotrophomonas maltophilia) as a complication of an intraorbital foreign body--a case report and literature review]

This is a case report of a 53-year-old man, who presented in the Department of Ophthalmology with signs of orbital cellulitis on the right side, which developed over a few days following an injury. Computed tomography revealed inflammatory infiltration of the orbital soft tissues, penetrating to the sella turcica. Orbital swab and blood cultures revealed the presence of Enterobacter and Peptostreptococcus spp. as well as Stenotrophomonas maltophilia, respectively. Review of the literature relevant to the presented case was performed based on the PubMed databasesearch, using the following keywords: intraorbital foreign body, orbital cellulitis, neuroinfection, Stenotrophomonas maltophiia.. Summarizing, the orbital injury-associated infections can be potentially life-threatening, due to the proximity of the anterior cranial fossa. Hence, they require prompt diagnosis and intensive treatment.

Antibiotic treatment for Stenotrophomonas maltophilia in people with cystic fibrosis

BACKGROUND

Stenotrophomonas maltophilia is one of the most common emerging multi-drug resistant organisms found in the lungs of people with cystic fibrosis and its prevalence is increasing. Chronic infection with Stenotrophomonas maltophilia has recently been shown to be an independent predictor of pulmonary exacerbation requiring hospitalization and antibiotics. However, the role of antibiotic treatment of Stenotrophomonas maltophilia infection in people with cystic fibrosis is still unclear.

OBJECTIVES

The objective of our review is to assess the effectiveness of antibiotic treatment for Stenotrophomonas maltophilia in people with cystic fibrosis. The primary objective is to assess this in relation to lung function and pulmonary exacerbations in the setting of acute pulmonary exacerbations. The secondary objective is to assess this in relation to the eradication of Stenotrophomonas maltophilia.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. We also searched a registry of ongoing trials and the reference lists of relevant articles and reviews.Date of latest search: 20 February 2014.

SELECTION CRITERIA

Any randomized controlled trial of Stenotrophomonas maltophilia mono-infection or Stenotrophomonas maltophilia co-infection with Pseudomonas aeruginosa in either the setting of an acute pulmonary exacerbation or a chronic infection treated with suppressive antibiotic therapy.

DATA COLLECTION AND ANALYSIS

Both authors independently assessed the trials identified by the search for potential inclusion in the review.

MAIN RESULTS

The initial search strategy identified only one study of antibiotic treatment of pulmonary exacerbations that included cystic fibrosis patients with Stenotrophomonas maltophilia. However, this study had to be excluded because data was not available per pathogen.

AUTHORS' CONCLUSIONS

This review did not identify any evidence regarding the effectiveness of antibiotic treatment for Stenotrophomonas maltophilia in people with cystic fibrosis. Until such evidence becomes available, clinicians need to use their clinical judgement as to whether or not to treat Stenotrophomonas maltophilia infection in patients with cystic fibrosis. Randomized clinical trials are needed to address these unanswered clinical questions.

Clinical and histopathologic findings in cutaneous sting ray wounds: a case report

Human injuries related to stingray attacks include deep puncture wounds, envenomation, and foreign body reactions owing to retained tail fragments. Herein we report a patient who sustained a stingray injury that produced a subcutaneous granulomatous dermatitis and panniculitis with necrobiosis and review the topic of stingray injuries.

Severe brain damage in premature infants associated with postnatal infection

AIM

This study examined clinical features and neuroimaging characteristics of severe brain damage in premature infants with postnatal infection.

METHODS

We retrospectively analyzed clinical data of two preterm infants who developed extensive encephalomalacia secondary to postnatal infection.

RESULTS

Two premature boys experienced serious postnatal infection at about 3 weeks after birth; the infection was characterized by lethargy, apnea, increased CRP, severe bilateral pneumonia, positive sputum culture for multidrug-resistant bacteria, and mild changes of cerebrospinal fluid. Both infants required ventilation and antibiotic therapy. While both infants survived, a very extensive encephalomalacia was documented by serial cranial ultrasound, MRI and CT scans 3 to 4 weeks after postnatal infection. Their mothers had no premature ruptures of membranes and no signs of antenatal infection, suggesting potential postnatal infection in the infants.

CONCLUSION

More studies are needed to better understand the underlying mechanism of encephalomalacia associated with postnatal infection. To facilitate early diagnosis and effective treatment, cranial ultrasound scans should be done routinely in premature infants with serious postnatal infection.

[Biological characteristics of phage SM1 for Stenotrophomonas maltophilia and its effect in animal infection model]

OBJECTIVE

To investigate the biological characteristics of phage SM1 for stenotrophomonas maltophilia (Sm) and its effect in animal infection model.

METHODS

Phage SM1 isolated from raw sewage of hospital was identified by the plaque method. The morphology of phage SM1 was observed by electron micrographics with negative staining. The extraction and electrophoresis of phage SM1 DNA were performed. Optimal multiplicity of infection, resistant mutation rate, one step growth curve and the effectiveness in animal models of phage SM1 were determined.

RESULTS

One Sm specific phage of myoviridae double-stranded DNA was identified, and named SM1. Electrophoresis of DNA demonstrated that the size of phage SM1 genome was about 50 kb. The growth curve of phage SM1 showed that the durations of incubation and burst period were 15 min and 50 min, respectively; and the burst size was 187. The resistant mutation rate of phage SM1 was 6 x 10(-10). All mice treated with phage SM1 survived after 7 d of infection with stenotrophomonas maltophilia.

CONCLUSION

The phage SM1 has a relatively broad host range, a shorter incubation period,an apparent burst size and a lower resistant mutation rate. The therapy of phage SM1 for Sm infection in mice is effective.

Non healing legs ulcers infected with Stenotrophomonas maltophilia

Stenotrophomonas maltophilia (S.M.) is a Gram-negative bacillus, naturally resistant to cephalosporins and carbapenems, which can colonize different sites and may be responsible for serious infections for which treatment is a real challenge. This was rarely reported as cutaneous pathogenic organism causing cellulitis-like lesions, paronychia, mucocutaneous ulcers and ecthyma gangrenosum in immunocompromised individuals. We report a case of non-healing legs ulcer infected with Stenotrophomonas maltophilia.

Stenotrophomonas maltophilia infections in a general hospital: patient characteristics, antimicrobial susceptibility, and treatment outcome

Introduction

Stenotrophomonas maltophilia is acquiring increasing importance as a nosocomial pathogen.

Methods

We retrospectively studied the characteristics and outcome of patients with any type of S. maltophilia infection at the University Hospital of Heraklion, Crete, Greece, between 1/2005–12/2010. S. maltophilia antimicrobial susceptibility was tested with the agar dilution method. Prognostic factors for all-cause in-hospital mortality were assessed with multivariate logistic regression.

Results

Sixty-eight patients (median age: 70.5 years; 64.7% males) with S. maltophilia infection, not related to cystic fibrosis, were included. The 68 patients were hospitalized in medical (29.4%), surgical (26.5%), hematology/oncology departments (23.5%), or the intensive care units (ICU; 20.6%). The most frequent infection types were respiratory tract (54.4%), bloodstream (16.2%), skin/soft tissue (10.3%), and intra-abdominal (8.8%) infection. The S. maltophilia-associated infection was polymicrobial in 33.8% of the cases. In vitro susceptibility was higher to colistin (91.2%), trimethoprim/sulfamethoxazole and netilmicin (85.3% each), and ciprofloxacin (82.4%). The empirical and the targeted treatment regimens were microbiologically appropriate for 47.3% and 63.6% of the 55 patients with data available, respectively. Most patients received targeted therapy with a combination of agents other than trimethoprim/sulfamethoxazole. The crude mortality and the mortality and the S. maltophilia infection-related mortality were 14.7% and 4.4%, respectively. ICU hospitalization was the only independent prognostic factor for mortality.

Conclusion

S. maltophilia infection in a general hospital can be associated with a good prognosis, except for the patients hospitalized in the ICU. Combination reigmens with fluoroquinolones, colistin, or tigecycline could be alternative treatment options to trimethoprim/sulfamethoxazole.

Antibiotic treatment for Stenotrophomonas maltophilia in people with cystic fibrosis

BACKGROUND

Stenotrophomonas maltophilia is one of the most common emerging multi-drug resistant organisms found in the lungs of people with cystic fibrosis and its prevalence is increasing. Chronic infection with Stenotrophomonas maltophilia has recently been shown to be an independent predictor of pulmonary exacerbation requiring hospitalization and antibiotics. However, the role of antibiotic treatment of Stenotrophomonas maltophilia infection in people with cystic fibrosis is still unclear.

OBJECTIVES

The objective of our review is to assess the effectiveness of antibiotic treatment for Stenotrophomonas maltophilia in people with cystic fibrosis. The primary objective is to assess this in relation to lung function and pulmonary exacerbations in the setting of acute pulmonary exacerbations. The secondary objective is to assess this in relation to the eradication of Stenotrophomonas maltophilia.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. We also searched a registry of ongoing trials and the reference lists of relevant articles and reviews.Date of latest search: 06 July 2011.

SELECTION CRITERIA

Any randomized controlled trial of Stenotrophomonas maltophilia mono-infection or Stenotrophomonas maltophilia co-infection with Pseudomonas aeruginosa in either the setting of an acute pulmonary exacerbation or a chronic infection treated with suppressive antibiotic therapy.

DATA COLLECTION AND ANALYSIS

Both authors independently assessed the trials identified by the search for potential inclusion in the review.

MAIN RESULTS

The initial search strategy identified only one study of antibiotic treatment of pulmonary exacerbations that included cystic fibrosis patients with Stenotrophomonas maltophilia. However, this study had to be excluded because data was not available per pathogen.

AUTHORS' CONCLUSIONS

This review did not identify any evidence regarding the effectiveness of antibiotic treatment for Stenotrophomonas maltophilia in people with cystic fibrosis. Until such evidence becomes available, clinicians need to use their clinical judgement as to whether or not to treat Stenotrophomonas maltophilia infection in patients with cystic fibrosis. Randomized clinical trials are needed to address these unanswered clinical questions.

[A case-control study on the risk factors for lower respiratory tract infection by Stenotrophomonas maltophilia in a medical intensive care unit]

OBJECTIVE

To explore the risk factors for lower respiratory tract infection by Stenotrophomonas maltophilia in the medical intensive care unit (MICU) in Fujian Provincial Hospital.

METHODS

A 1:4 matched case-control study was carried out in the MICU in Fujian Provincial Hospital. Thirty-five patients with hospital-acquired lower respiratory tract infection by Stenotrophomonas maltophilia from 2007 to 2010 were included as cases, and 140 patients without lower respiratory tract infection served as controls. The case group included 22 cases with respiratory diseases, 4 with cerebrovascular diseases, 4 with cardiovascular diseases, 1 with hemorrhage of the digestive tract, 1 with acute pancreatitis, 1 with chronic kidney disease, 1 with cervical cancer and 1 with Alzheimer's disease. While the control group included 30 cases with respiratory diseases, 44 with cerebrovascular diseases, 14 with cardiovascular diseases, 2 with malignant tumors and 50 with others. Patients' information, general situation before being admitted to MICU, drug therapy, invasive procedures and hospital-acquired infection were analyzed. Conditional logistic regression was performed to identify independent risk factors.

RESULTS

Univariate analysis showed that factors such as more than 4 underlying diseases (OR = 4.63), APACHE-II score ≥ 20(OR = 10.29), stay in the general ward more than 1 week before being admitted to MICU, treatment with more than 3 kinds of antibiotics (OR = 8.03), endotracheal intubation (OR = 4.10) or tracheotomy (OR = 50.29) and mechanical ventilation (OR = 7.95) were risk factors for hospital-acquired lower respiratory tract infection by Stenotrophomonas maltophilia. Multivariate logistic regression showed that variables such as APACHE-II score (OR = 8.39), kinds of antibiotics used (OR = 5.96) and tracheotomy (OR = 28.92) were independent risk factors (P < 0.01).

CONCLUSIONS

Underlying diseases, the severity of diseases, tracheotomy, mechanical ventilation, and the use of wide-spectrum antibiotics are important risk factors for lower respiratory tract infection by Stenotrophomonas maltophilia in MICU. To identify these factors and take preventive measures earlier may be useful for decreasing Stenotrophomonas maltophilia infection-related mortality.

The emergence of Stenotrophomonas maltophilia

Superbug or opportunist?

Emerging and Unusual Gram-Negative Infections in Cystic Fibrosis

People with cystic fibrosis (CF) have chronic airway infection and frequent exposure to antibiotics, which often leads to the emergence of resistant organisms. In addition to the development of multiresistance in common CF pathogens such as Pseudomonas aeruginosa, several newer, inherently resistant gram-negative species are becoming more common, including Burkholderia cepacia complex, Stenotrophomonas maltophilia, Achromobacter (Alcaligenes) xylosoxidans, certain Ralstonia species, and those within the new genus Pandoraea. Many of these are closely related and have similar phenotypes, making accurate laboratory identification challenging. Although their role in contributing to pulmonary disease in CF is not clear, some, such as those of the B. cepacia complex, are clearly linked to an adverse prognosis, and both treatment and infection control issues can pose a real challenge.

[Mesenteric vein thrombosis and protein C and S deficiency in a patient with chronic hepatitis C on treatment with interferon and ribavirin]

We describe the case of a 67 year old male with chronic hepatitis C on treatment with pegylated interferon and ribavirin who, after two and a half months of combined treatment, presented with a picture of acute mesenteric vein thrombosis that required urgent surgery. It re-occurred several days later and was his cause of death. In the thrombophilia study carried out immediately after surgery a decrease in protein C and S was considered as a cause of hypercoagulability. Protein C and S deficiency, natural anticoagulants synthesised in the liver, in patients without hepatic disease is a known cause of mesenteric thrombosis. Its decrease has also been described in the context of chronic hepatic diseases, including C virus chronic hepatitis, although it is not known for sure if this hypercoagulability state is a primary or secondary manifestation. Chronic hepatitis C and treatment with interferon has often been associated with a procoagulant state, and on many occasions due to different factors and mechanisms.

[Primary intracerebral hemorrhage due to probable cerebral amyloid angiopathy complicated by brain abscess: case report]

Cerebral amyloid angiopathy (CAA), in which deposition of amyloid within the arterial media and adventitia is the remarkable feature, causes spontaneous lober cerebral hemorrhage in elderly person, and some reports show the quite high occurrence rate of this entity among intracerebral hemorrhage in patents above 70 years old. Brain abscess resulting from intracerebral hemorrhage is rare. To our knowledge, no report of such hemorrhage which is caused by CAA has been published so far. We report a case of brain abscess, from which Stenotrophomonas maltophilia was isolated, following spontaneous non-hypertensive intracerebral hemorrhage caused by probable CAA, with a review of the relevant literature.

Stenotrophomonas maltophilia pneumonia after bone marrow transplantation: case report with emphasis on the high-resolution CT findings

A 6-year-old female patient who underwent bone marrow transplantation because of Fanconi anaemia presented with fever, dyspnoea and cough 17 days after the procedure. The physical examination revealed diffuse crackles. Chest radiographs demonstrated diffuse alveolar opacities in both lungs. High-resolution CT showed a diffuse and bilateral lung lesion characterized by multifocal areas of air-space consolidation associated with ground-glass attenuation and small centrilobular nodules. The culture of the material obtained with bronchoalveolar lavage only demonstrated growth of Stenotrophomonas maltophilia. The patient rapidly presented respiratory insufficiency and death in the same day.

Intensive care unit-acquired Stenotrophomonas maltophilia: incidence, risk factors, and outcome

Introduction

The aim of this study was to determine incidence, risk factors, and impact on outcome of intensive care unit (ICU)-acquired Stenotrophomonas maltophilia.

Methods

This prospective observational case-control study, which was a part of a cohort study, was conducted in a 30-bed ICU during a three year period. All immunocompetent patients hospitalised >48 hours were eligible. Patients with non-fermenting Gram-negative bacilli (NF-GNB) at ICU admission were excluded. Patients without ICU-acquired S. maltophilia who developed an ICU-acquired NF-GNB other than S. maltophilia were also excluded. Screening (tracheal aspirate and skin, anal, and nasal swabs) for NF-GNB was performed in all patients at ICU admission and weekly. Univariate and multivariate analyses were performed to determine risk factors for ICU-acquired S. maltophilia and for ICU mortality.

Results

Thirty-eight (2%) patients developed an S. maltophilia ICU-acquired colonisation and/or infection and were all successfully matched with 76 controls. Chronic obstructive pulmonary disease (COPD) and duration of antibiotic treatment (odds ratio [OR] [95% confidence interval (CI)] = 9.4 [3 to 29], p < 0.001, and 1.4 [1 to 2.3], p = 0.001, respectively) were independently associated with ICU-acquired S. maltophilia. Mortality rate (60% versus 40%, OR [95% CI] = 1.3 [1 to 1.7, p = 0.037]), duration of mechanical ventilation (23 ± 16 versus 7 ± 11 days, p < 0.001), and duration of ICU stay (29 ± 21 versus 15 ± 17 days, p < 0.001) were significantly higher in cases than in controls. In addition, ICU-acquired infection related to S. maltophilia was independently associated with ICU mortality (OR [95% CI] = 2.8 [1 to 7.7], p = 0.044).

Conclusion

COPD and duration of antibiotic treatment are independent risk factors for ICU-acquired S. maltophilia. ICU-acquired S. maltophilia is associated with increased morbidity and mortality rates. ICU-acquired infection related to S. maltophilia is an independent risk factor for ICU mortality.

Skin manifestation of Stenotrophomonas maltophilia infection--a case report and review article

INTRODUCTION

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.

MATERIALS AND METHODS

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.

RESULTS

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.

CONCLUSION

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.