Stenotrophomonas maltophilia


With the widespread use of antibiotics and dramatic improvement in patients survival, newer organisms, such as Stenotrophomonas maltophilia (Denton et al, 1996; Denton et al, 1998; Talmaciu et al, 2000; Krzewinski et al, 2001), Achromobacter xylosoxidans (Dunne & Maisch, 1995; Krzewinski et al, 2001; Tan et al, 2002) and nontuberculous mycobacteria (Tomashefski et al, 1996; Torrens et al, 1998; Olivier et al, 2003) are becoming more widespread. The reasons for their emergence are complex but may relate to the selective pressure exerted by repeated exposure to antibiotic therapy, improved laboratory isolation techniques and enhanced reporting. All may be associated with either simple colonisation or respiratory exacerbations in those persistently colonised with large numbers of these organisms.

Stenotrophomonas maltophilia

The reported prevalence of S. maltophilia in CF Centres is typically 15-20% (Denton, 1997), although most patients appear only intermittently rather than chronically colonised. The main risk factor for acquisition appears to be the selective antibiotic pressure (Denton et al, 1996; Talmaciu et al, 2000; Marchac et al, 2004). The organism is widespread in the home and hospital environments, particularly in water sources (Denton et al, 1998). Equipment used to deliver aerosolised therapy may also be contaminated with S. maltophilia (Denton et al, 2003) and act as a source of infection. Studies have failed to show a clear clinical impact of S. maltophilia on people with CF (Goss et al, 2002; Goss et al, 2004). Therefore the need for, and optimum approach to therapy, remain uncertain. Most evidence suggests that cotrimoxazole (‘Septrin’) has the greatest efficacy against S. maltophilia (Conway et al, 2003). Although a study specifically using isolates from people with CF found high levels of resistance (San Gabriel et al, 2004), cotrimoxazole was often synergistic when used in combination with agents such as ticarcillin-clavulanate (‘Timentin’) or piperacillin-tazobactam (‘Tazocin’). Other agents with frequent in vitro activity against S. maltophilia include tetracyclines (e.g. minocycline, doxycycline), ceftazidime, colistin and tigecycline (Insa et al, 2007).

Key points

• Prevalence of S. maltophilia in CF Centres is typically 15-20%

• The organism is widespread in the home and hospital environments

• Studies have failed to show a clear clinical impact of S. maltophilia on people with CF


Conway SP, Brownlee KG, Denton M, et al. Antibiotic treatment of multidrug-resistant organisms in cystic fibrosis. Am J Respir Med 2003; 2: 321-332.[PubMed]

Denton M, Todd NJ, Littlewood JM. Role of anti-pseudomonal antibiotics in the emergence of Stenotrophomonas maltophilia in cystic fibrosis patients. Eur J Clin Microbiol Infect Dis 1996; 15: 402-405. [PubMed]

Denton M. Stenotrophomonas maltophilia: an emerging problem in cystic fibrosis patients. Rev Med Microbiol 1997; 8: 15-19.

Denton M, Todd NJ, Kerr KG, et al. Molecular epidemiology of Stenotrophomonas maltophilia isolated from clinical specimens from patients with cystic fibrosis and associated environmental samples. J Clin Microbiol 1998; 36: 1953-1958. [PubMed]

Denton M, Rajgopal A, Mooney L, et al. Stenotrophomonas maltophilia contamination of nebulizers used to deliver aerosolized therapy to in-patients with cystic fibrosis. J Hosp Infect 2003; 55:180-183.[PubMed]

Dunne WM Jr, Maisch S. Epidemiological investigation of infections due to Alcaligenes species in children and patients with cystic fibrosis: use of repetitive-element sequence polymerase chain reaction. Clin Infect Dis 1995; 20: 836-841. [PubMed]

Goss CH, Otto K, Aitken ML, et al. Detecting Stenotrophomonas maltophilia does not reduce survival of patients with cystic fibrosis. Am J Respir Crit Care Med 2002; 166: 356-361. [PubMed]

Goss CH, Mayer-Hamblett N, Aitken ML, et al. Association between Stenotrophomonas maltophilia and lung function in cystic fibrosis. Thorax 2004; 59: 955-959. [PubMed]

Insa R, Cercenado E, Goyanes MJ, et al. In-vitro activity of tigecycline against clinical isolates of Acinetobacter baumannii and Stenotrophomonas maltophilia. J Antimicrob Chemother 2007; 59: 583-585. [PubMed]

Krzewinski JW, Nguyen CD, Foster JM, et al. Use of random amplified polymorphic DNA PCR to examine epidemiology of Stenotrophomonas maltophilia and Achromobacter (Alcaligenes) xylosoxidans from patients with cystic fibrosis. J Clin Microbiol 2001; 39: 3597-3602. [PubMed]

Marchac V, Equi A, Le Bihan-Benjamin C, et al. Case-control study of Stenotrophomonas maltophilia acquisition in cystic fibrosis patients. Eur Respir J 2004; 23: 98-102. [PubMed]

Olivier KN, Weber DJ, Wallace RJ Jr, et al. Nontuberculous mycobacteria I: multicenter prevalence study in cystic fibrosis. Am J Respir Crit Care Med 2003; 15: 828-834. [PubMed]

San Gabriel P, Zhou J, Tabibi S, et al. Antimicrobial susceptibility and synergy studies of Stenotrophomonas maltophilia isolates from patients with cystic fibrosis. Antimicrob Agents Chemother 2004; 48: 168-171. [PubMed]

Talmaciu I, Varlotta L, Mortensen J, et al. Risk factors for emergence of Stenotrophomonas maltophilia in cystic fibrosis. Pediatr Pulmonol 2000; 30: 10-15. [PubMed]

Tan K, Conway SP, Brownlee KG, et al. Alcaligenes infection in cystic fibrosis. Pediatr Pulmonol 2002; 34:101-104 .[PubMed]

Tomashefski JF Jr, Stern R, Demko CA, et al. Nontuberculous mycobacteria in cystic fibrosis. An autopsy study. Am J Respir Crit Care Med 1996; 154: 523-528. [PubMed]

Torrens JK, Dawkins P, Conway SP, et al. Non-tuberculous mycobacteria in cystic fibrosis. Thorax 1998; 53: 182-185. [PubMed]