Aurélie Chauffour1, Florence Morel2, Florence Reibel3, Stéphanie Petrella4, Claudine Mayer4, Emmanuelle Cambau5, Alexandra Aubry6. 1. Sorbonne Université, INSERM, U1135, Centre d'Immunologie et des Maladies Infectieuses, Cimi-Paris, Paris, France. 2. Sorbonne Université, INSERM, U1135, Centre d'Immunologie et des Maladies Infectieuses, Cimi-Paris, Paris, France; AP-HP, Sorbonne-Université, Hôpital Pitié-Salpêtrière, Centre National de Référence des Mycobactéries et de la Résistance des Mycobactéries aux Antituberculeux, Paris, France. 3. Sorbonne Université, INSERM, U1135, Centre d'Immunologie et des Maladies Infectieuses, Cimi-Paris, Paris, France; AP-HP, Sorbonne-Université, Hôpital Pitié-Salpêtrière, Centre National de Référence des Mycobactéries et de la Résistance des Mycobactéries aux Antituberculeux, Paris, France; Laboratoire de Biologie, Groupe Hospitalier Nord-Essonne, Site de Longjumeau, Longjumeau, France. 4. Unité de Microbiologie Structurale, Institut Pasteur, CNRS UMR 3528, Paris, France; Université Paris Diderot, Sorbonne Paris Cité, Paris, France. 5. AP-HP GHU Nord, Service de Mycobactériologie Spécialisée et de Référence, Centre National de Référence des Mycobactéries et de la Résistance des Mycobactéries aux Antituberculeux, Paris, France; Université de Paris, Paris Diderot, INSERM, IAME UMR1137, Paris, France. 6. Sorbonne Université, INSERM, U1135, Centre d'Immunologie et des Maladies Infectieuses, Cimi-Paris, Paris, France; AP-HP, Sorbonne-Université, Hôpital Pitié-Salpêtrière, Centre National de Référence des Mycobactéries et de la Résistance des Mycobactéries aux Antituberculeux, Paris, France. Electronic address: alexandra.aubry@sorbonne-universite.fr.
Abstract
BACKGROUND: The fact that Mycobacterium leprae does not grow in vitro remains a challenge in the survey of its antimicrobial resistance (AMR). Mainly molecular methods are used to diagnose AMR in M. leprae to provide reliable data concerning mutations and their impact. Fluoroquinolones (FQs) are efficient for the treatment of leprosy and the main second-line drugs in case of multidrug resistance. OBJECTIVES: This study aimed at performing a systematic review (a) to characterize all DNA gyrase gene mutations described in clinical isolates of M. leprae, (b) to distinguish between those associated with FQ resistance or susceptibility and (c) to delineate a consensus numbering system for M. leprae GyrA and GyrB. DATA SOURCES: Data source was PubMed. STUDY ELIGIBILITY CRITERIA: Publications reporting genotypic susceptibility-testing methods and gyrase gene mutations in M. leprae clinical strains. RESULTS: In 25 studies meeting our inclusion criteria, 2884 M. leprae isolates were analysed (2236 for gyrA only (77%) and 755 for both gyrA and gyrB (26%)): 3.8% of isolates had gyrA mutations (n = 110), mostly at position 91 (n = 75, 68%) and 0.8% gyrB mutations (n = 6). Since we found discrepancies regarding the location of substitutions associated with FQ resistance, we established a consensus numbering system to properly number the mutations. We also designed a 3D model of the M. leprae DNA gyrase to predict the impact of mutations whose role in FQ-susceptibility has not been demonstrated previously. CONCLUSIONS: Mutations in DNA gyrase are observed in 4% of the M. leprae clinical isolates. To solve discrepancies among publications and to distinguish between mutations associated with FQ resistance or susceptibility, the consensus numbering system we proposed as well as the 3D model of the M. leprae gyrase for the evaluation of the impact of unknown mutations in FQ resistance, will provide help for resistance surveillance.
BACKGROUND: The fact that Mycobacterium leprae does not grow in vitro remains a challenge in the survey of its antimicrobial resistance (AMR). Mainly molecular methods are used to diagnose AMR in M. leprae to provide reliable data concerning mutations and their impact. Fluoroquinolones (FQs) are efficient for the treatment of leprosy and the main second-line drugs in case of multidrug resistance. OBJECTIVES: This study aimed at performing a systematic review (a) to characterize all DNA gyrase gene mutations described in clinical isolates of M. leprae, (b) to distinguish between those associated with FQ resistance or susceptibility and (c) to delineate a consensus numbering system for M. leprae GyrA and GyrB. DATA SOURCES: Data source was PubMed. STUDY ELIGIBILITY CRITERIA: Publications reporting genotypic susceptibility-testing methods and gyrase gene mutations in M. leprae clinical strains. RESULTS: In 25 studies meeting our inclusion criteria, 2884 M. leprae isolates were analysed (2236 for gyrA only (77%) and 755 for both gyrA and gyrB (26%)): 3.8% of isolates had gyrA mutations (n = 110), mostly at position 91 (n = 75, 68%) and 0.8% gyrB mutations (n = 6). Since we found discrepancies regarding the location of substitutions associated with FQ resistance, we established a consensus numbering system to properly number the mutations. We also designed a 3D model of the M. leprae DNA gyrase to predict the impact of mutations whose role in FQ-susceptibility has not been demonstrated previously. CONCLUSIONS: Mutations in DNA gyrase are observed in 4% of the M. leprae clinical isolates. To solve discrepancies among publications and to distinguish between mutations associated with FQ resistance or susceptibility, the consensus numbering system we proposed as well as the 3D model of the M. leprae gyrase for the evaluation of the impact of unknown mutations in FQ resistance, will provide help for resistance surveillance.