Chien-Jung Pien1, Han-Yueh Kuo2, Shu-Wen Chang3, Pei-Ru Chen3, Hui-Wen Yeh4, Chih-Chin Liu5, Ming-Li Liou6. 1. Division of Infectious Disease, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan. 2. Department of Internal Medicine, National Taiwan University Hospital Hsin-Chu Branch, Hsin-Chu City, Taiwan; School of Medicine, National Yang-Ming University, Taipei, Taiwan; School of Medicine, National Taiwan University, Taipei, Taiwan. 3. Department of Medical Laboratory Medicine and Biotechnology, Yuanpei University, Hsin-Chu City, Taiwan. 4. Department of Laboratory Medicine, National Taiwan University Hospital Hsin-Chu branch, Hsin-Chu City, Taiwan. 5. Department of Bioinformatics, Chung Hua University, Hsin-Chu City, Taiwan. 6. Department of Medical Laboratory Medicine and Biotechnology, Yuanpei University, Hsin-Chu City, Taiwan; Department of Computer Science and Information Engineering, Providence University, Taichung City, Taiwan. Electronic address: actt19604@gmail.com.
Abstract
OBJECTIVES: Stenotrophomonas maltophilia is a bacterial pathogen associated with health-care associated infections, particularly in immunocompromised patients. Members of the fluoroquinolone drug class are frequently used to treat S. maltophilia infection; however, S. maltophilia resistance to fluoroquinolones, especially levofloxacin, has been increasing. METHODS: We sought to identify risk factors associated with levofloxacin resistance using a case-control study. We examined sputum from 76 S. maltophilia-positive patients admitted to our hospital between January 1, 2010 and June 30, 2011. Case groups were defined as patients who had S. maltophilia infections resistant to levofloxacin, and control groups were defined as patients who had S. maltophilia infections susceptible to levofloxacin treatment. Patient information including demographics, previous antibiotic use, and other traits were recorded. In addition, S. maltophilia isolates from patient sputum were assessed for antibiotic resistance as well as for the presence of genes associated with drug resistance. RESULTS: Previous antibiotic treatment with first- or second-generation cephalosporin was found more often in the levofloxacin-susceptible group; by contrast, previous piperacillin/tazobactam treatment occurred more often in the levofloxacin-resistant group. Three genes associated with drug resistance, including SmeA, SmeD, and SpgM were not significantly different between these groups. CONCLUSION: Piperacillin/tazobactam treatment is associated with subsequent isolation of levofloxacin-resistant S. maltophilia from the respiratory tract.
OBJECTIVES:Stenotrophomonas maltophilia is a bacterial pathogen associated with health-care associated infections, particularly in immunocompromised patients. Members of the fluoroquinolone drug class are frequently used to treat S. maltophilia infection; however, S. maltophilia resistance to fluoroquinolones, especially levofloxacin, has been increasing. METHODS: We sought to identify risk factors associated with levofloxacin resistance using a case-control study. We examined sputum from 76 S. maltophilia-positivepatients admitted to our hospital between January 1, 2010 and June 30, 2011. Case groups were defined as patients who had S. maltophilia infections resistant to levofloxacin, and control groups were defined as patients who had S. maltophilia infections susceptible to levofloxacin treatment. Patient information including demographics, previous antibiotic use, and other traits were recorded. In addition, S. maltophilia isolates from patient sputum were assessed for antibiotic resistance as well as for the presence of genes associated with drug resistance. RESULTS: Previous antibiotic treatment with first- or second-generation cephalosporin was found more often in the levofloxacin-susceptible group; by contrast, previous piperacillin/tazobactam treatment occurred more often in the levofloxacin-resistant group. Three genes associated with drug resistance, including SmeA, SmeD, and SpgM were not significantly different between these groups. CONCLUSION:Piperacillin/tazobactam treatment is associated with subsequent isolation of levofloxacin-resistant S. maltophilia from the respiratory tract.