Tags

Type your tag names separated by a space and hit enter

Rifaximin-resistant Clostridium difficile strains isolated from symptomatic patients.
Anaerobe. 2017 Dec; 48:269-272.A

Abstract

BACKGROUND

Rifaximin has been proposed as an alternative treatment for specific cases of Clostridium difficile infection (CDI) and intestinal decontamination. Rifaximin-resistant C. difficile has occasionally been reported. Antibiotic susceptibility testing relies on anaerobic agar dilution (reference method), which is cumbersome and not routinely used. There is no commercial test for detection of resistance to rifaximin.

OBJECTIVES

To assess resistance to rifaximin by C. difficile and to evaluate the correlation between the results of the rifampicin E-test and susceptibility to rifaximin.

METHODS

We compared the in vitro susceptibility of clinical CDI isolates to rifaximin over a 6-month period using the agar dilution method with susceptibility to rifampicin using the E-test. All isolates were characterized using PCR-ribotyping. Clinical data were recorded prospectively.

RESULTS

We recovered 276 consecutive C. difficile isolates and found that 32.2% of episodes were caused by rifaximin-resistant strains. The MICs for rifaximin ranged from <0.0009-256 mg/L, with a geometric mean (GM) of 0.256 mg/L, an MIC50/90 of 0.015/>256 mg/L. Rifaximin and rifampicin MICs were comparable, and all strains classed as resistant by agar dilution were correctly classified as resistant by E-test. The most common ribotypes were 001 (37.2%), 078/126 (14.3%), and 014 (12.0%). Ribotype 001 exhibited the highest MICs for rifaximin.

CONCLUSIONS

Resistance to rifaximin was common; resistance rates were higher in ribotype 001 strains. Susceptibility to rifaximin determined by agar dilution correlated with susceptibility to rifampicin determined using the E-test, including rifaximin-resistant strains. Our results suggest that the rifampicin E-test is a valid method for the prediction of rifaximin-resistant C. difficile.

Authors+Show Affiliations

Department of Clinical Microbiology and Infectious Diseases, Hospital General Universitario Gregorio Marañón, Madrid, Spain; Medicine Department, School of Medicine, Universidad Complutense de Madrid (UCM), Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain. Electronic address: helenrei@hotmail.com.Department of Clinical Microbiology and Infectious Diseases, Hospital General Universitario Gregorio Marañón, Madrid, Spain.Department of Clinical Microbiology and Infectious Diseases, Hospital General Universitario Gregorio Marañón, Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain.Department of Clinical Microbiology and Infectious Diseases, Hospital General Universitario Gregorio Marañón, Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain; CIBER de Enfermedades Respiratorias (CIBERES CB06/06/0058), Madrid, Spain.Department of Clinical Microbiology and Infectious Diseases, Hospital General Universitario Gregorio Marañón, Madrid, Spain; Medicine Department, School of Medicine, Universidad Complutense de Madrid (UCM), Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain; CIBER de Enfermedades Respiratorias (CIBERES CB06/06/0058), Madrid, Spain.Department of Clinical Microbiology and Infectious Diseases, Hospital General Universitario Gregorio Marañón, Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain.Department of Clinical Microbiology and Infectious Diseases, Hospital General Universitario Gregorio Marañón, Madrid, Spain; Medicine Department, School of Medicine, Universidad Complutense de Madrid (UCM), Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain; CIBER de Enfermedades Respiratorias (CIBERES CB06/06/0058), Madrid, Spain. Electronic address: emilio.bouza@gmail.com.

Pub Type(s)

Journal Article

Language

eng

PubMed ID

28988773

Citation

Reigadas, E, et al. "Rifaximin-resistant Clostridium Difficile Strains Isolated From Symptomatic Patients." Anaerobe, vol. 48, 2017, pp. 269-272.
Reigadas E, Muñoz-Pacheco P, Vázquez-Cuesta S, et al. Rifaximin-resistant Clostridium difficile strains isolated from symptomatic patients. Anaerobe. 2017;48:269-272.
Reigadas, E., Muñoz-Pacheco, P., Vázquez-Cuesta, S., Alcalá, L., Marín, M., Martin, A., & Bouza, E. (2017). Rifaximin-resistant Clostridium difficile strains isolated from symptomatic patients. Anaerobe, 48, 269-272. https://doi.org/10.1016/j.anaerobe.2017.10.002
Reigadas E, et al. Rifaximin-resistant Clostridium Difficile Strains Isolated From Symptomatic Patients. Anaerobe. 2017;48:269-272. PubMed PMID: 28988773.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Rifaximin-resistant Clostridium difficile strains isolated from symptomatic patients. AU - Reigadas,E, AU - Muñoz-Pacheco,P, AU - Vázquez-Cuesta,S, AU - Alcalá,L, AU - Marín,M, AU - Martin,A, AU - Bouza,E, Y1 - 2017/10/06/ PY - 2017/07/28/received PY - 2017/09/14/revised PY - 2017/10/05/accepted PY - 2017/10/11/pubmed PY - 2018/6/22/medline PY - 2017/10/10/entrez KW - Antimicrobial susceptibility KW - C. difficile KW - Ribotype KW - Rifampicin KW - Rifaximin SP - 269 EP - 272 JF - Anaerobe JO - Anaerobe VL - 48 N2 - BACKGROUND: Rifaximin has been proposed as an alternative treatment for specific cases of Clostridium difficile infection (CDI) and intestinal decontamination. Rifaximin-resistant C. difficile has occasionally been reported. Antibiotic susceptibility testing relies on anaerobic agar dilution (reference method), which is cumbersome and not routinely used. There is no commercial test for detection of resistance to rifaximin. OBJECTIVES: To assess resistance to rifaximin by C. difficile and to evaluate the correlation between the results of the rifampicin E-test and susceptibility to rifaximin. METHODS: We compared the in vitro susceptibility of clinical CDI isolates to rifaximin over a 6-month period using the agar dilution method with susceptibility to rifampicin using the E-test. All isolates were characterized using PCR-ribotyping. Clinical data were recorded prospectively. RESULTS: We recovered 276 consecutive C. difficile isolates and found that 32.2% of episodes were caused by rifaximin-resistant strains. The MICs for rifaximin ranged from <0.0009-256 mg/L, with a geometric mean (GM) of 0.256 mg/L, an MIC50/90 of 0.015/>256 mg/L. Rifaximin and rifampicin MICs were comparable, and all strains classed as resistant by agar dilution were correctly classified as resistant by E-test. The most common ribotypes were 001 (37.2%), 078/126 (14.3%), and 014 (12.0%). Ribotype 001 exhibited the highest MICs for rifaximin. CONCLUSIONS: Resistance to rifaximin was common; resistance rates were higher in ribotype 001 strains. Susceptibility to rifaximin determined by agar dilution correlated with susceptibility to rifampicin determined using the E-test, including rifaximin-resistant strains. Our results suggest that the rifampicin E-test is a valid method for the prediction of rifaximin-resistant C. difficile. SN - 1095-8274 UR - https://www.unboundmedicine.com/medline/citation/28988773/Rifaximin_resistant_Clostridium_difficile_strains_isolated_from_symptomatic_patients_ L2 - https://linkinghub.elsevier.com/retrieve/pii/S1075-9964(17)30197-X DB - PRIME DP - Unbound Medicine ER -