From the Guidelines
Stenotrophomonas maltophilia infections should be treated with trimethoprim-sulfamethoxazole (TMP-SMX) as the first-line treatment, with alternative options including fluoroquinolones, minocycline, or tigecycline for patients with sulfa allergies. The treatment of S. maltophilia infections is challenging due to its natural resistance to many antibiotics, including carbapenems, most beta-lactams, and aminoglycosides 1.
Key Considerations
- The first-line treatment for S. maltophilia infections is trimethoprim-sulfamethoxazole (TMP-SMX), typically dosed at 5-20 mg/kg/day of the trimethoprim component, divided into 2-4 doses for 7-14 days depending on infection severity.
- For patients with sulfa allergies, alternative options include fluoroquinolones (levofloxacin 750 mg daily or moxifloxacin 400 mg daily), minocycline (100 mg twice daily), or tigecycline (100 mg loading dose followed by 50 mg every 12 hours) 1.
- Combination therapy may be necessary for severe infections.
- Infection control measures, including proper hand hygiene and device management, are essential to prevent transmission in healthcare settings, as recommended by the ESCMID guidelines 1.
- Patients with cystic fibrosis, prolonged hospitalization, mechanical ventilation, or indwelling catheters are at higher risk for acquiring this opportunistic pathogen.
Infection Control Measures
- Contact precautions, including the use of gloves and gowns, should be implemented for all colonized patient encounters in all hospital settings to reduce the risk of acquisition 1.
- Environmental cleaning and disinfection, including the use of disinfectant agents and meticulous cleaning, should be performed to reduce transmission of S. maltophilia 1.
- Educational programs should be conducted to ensure that healthcare workers understand the importance of preventing the spread of S. maltophilia and the measures that have proven to be effective in preventing its transmission 1.
From the Research
Characteristics of Stenotrophomonas maltophilia
- Stenotrophomonas maltophilia is an emerged opportunistic pathogen 2
- It is a Gram-negative, biofilm-forming bacterium 3
- Intrinsic multidrug resistance makes treating infections caused by S. maltophilia a great clinical challenge 2
Resistance Mechanisms
- Intrinsic resistance may be due to reduced outer membrane permeability or to the multidrug efflux pumps 4
- Specific mechanisms of resistance such as aminoglycoside-modifying enzymes or the heterogeneous production of metallo-beta-lactamase have contributed to the multidrug-resistant phenotype displayed by this pathogen 4
- The presence of class 1 integrons and efflux pumps also contribute to its resistance to antibiotics 3
Treatment Options
- Trimethoprim-sulfamethoxazole (SXT) is recognized as the first-line therapy for S. maltophilia infections 2, 4, 3
- Other treatment options include levofloxacin (LVX), minocycline (MIN), ticarcillin-clavulanic acid, and tigecycline 4, 5, 3
- Novel therapeutic options such as cefiderocol (FDC) and ceftazidime-avibactam plus aztreonam (CZA-ATM) are suggested, based on limited but promising clinical data 2
- Combination therapy of SXT, LVX, MIN, or FDC, or monotherapy with CZA-ATM are recommended therapeutic options for severe-to-moderate S. maltophilia infections 2
Emerging Trends and Future Directions
- The prevalence of S. maltophilia infection in the general population is increasing 3
- There is an alarming trend in resistance to traditionally effective agents such as ceftazidime, ticarcillin-clavulanate, and fluoroquinolones 3
- Novel treatment strategies for Stenotrophomonas infection are desperately needed, and current research is focused on developing new therapies 6