L'antibiogramme des bactéries anaérobies stricts

Prevalence and antibiotic susceptibility trends of periodontal pathogens in the subgingival microbiota of German periodontitis patients: A retrospective surveillance study

“…Furthermore, anaerobic pathogens display higher variability of MIC and zone diameters when compared to aerobes and results are therefore more difficult to interpret (Dubreuil, 2020). Here, susceptibility testing of periodontal pathogens was performed by disc diffusion and interpreted according to the recommendations effective in the study period [summarized in (Dubreuil, 1995)]. Importantly, under EUCAST the methodology remains under development because standardization and, in particular interlaboratory reproducibility of breakpoints, is a major difficulty (Nagy et al, 2018; Dubreuil, 2020).…”

“…However, extrapolation to breakpoints used for interpretation in agar dilution and E‐test is not possible. Interpretation of zone diameters was further limited to differentiation of ‘susceptible’ from ‘non‐susceptible’ isolates, following the French guidelines effective in the study period (Dubreuil, 1995). Notably, resistance may have been underestimated because very recent methodological studies define areas of technical uncertainty (ATU) that lie beyond the zone diameters used formerly to avoid very major errors and major errors, for example, an ATU of 17–20 mm was defined for amoxicillin‐clavulanate (Dubreuil, 2020).…”

“…After 3–5 days under anaerobic conditions zone diameters were measured with a calliper and interpreted according to (Dubreuil, 1995; Podbielski et al, 2007). Zone diameter breakpoints for resistance were defined accordingly, for example, susceptibility was defined if zone diameters were equal to or lay above the following: amoxicillin ≥24 mm, amoxicillin plus clavulanate ≥15 mm, metronidazole ≥24 mm, azithromycin ≥20 mm, ampicillin/sulbactam ≥28 mm, doxycycline ≥28 mm, clindamycin ≥15 mm and ciprofloxacin ≥35 mm (Dubreuil, 1995). All zone diameters between ≥15 mm and <16 mm for clindamycin (zone of uncertainty) and those for metronidazole >15 mm and <24 mm (zone of uncertainty) were evaluated by E‐Test antibiotic gradient strips (BioMerieux) to confirm resistance.…”

“…Antibiotic discs (Oxoid™/Fisher Scientific) for in vitro susceptibility testing contained 10 μg amoxicillin (AML), 30 μg amoxicillin/clavulanic acid (AMC 2:1), 20 µg ampicillin/sulbactam (SAM 1:1), 30 μg doxycycline (DO), 2 μg clindamycin (DA), 15 μg azithromycin (AZM), 5 μg ciprofloxacin (CIP) or 5 μg metronidazole (MTZ). After 3–5 days under anaerobic conditions zone diameters were measured with a calliper and interpreted according to (Dubreuil, 1995; Podbielski et al, 2007). Zone diameter breakpoints for resistance were defined accordingly, for example, susceptibility was defined if zone diameters were equal to or lay above the following: amoxicillin ≥24 mm, amoxicillin plus clavulanate ≥15 mm, metronidazole ≥24 mm, azithromycin ≥20 mm, ampicillin/sulbactam ≥28 mm, doxycycline ≥28 mm, clindamycin ≥15 mm and ciprofloxacin ≥35 mm (Dubreuil, 1995).…”