The Inappropriateness of Using Rifampicin E-Test to Predict Rifabutin Resistance in Helicobacter pylori.
J Infect Dis
; 226(Suppl 5): S479-S485, 2022 12 08.
Article
in En
| MEDLINE
| ID: mdl-36478247
ABSTRACT
BACKGROUND:
The aim of this study was to evaluate the rifamycin cross-resistance in Helicobacter pylori, and whether the use of rifampicin E-test strips to screen H. pylori rifabutin resistance is appropriate.METHODS:
A total of 89 H. pylori isolates were included. Rifampicin minimum inhibitory concentrations (MICs) were obtained by E-test, while the MICs for rifapentine, rifaximin, and rifabutin were determined by agar dilution method. The rifamycin resistance rates based on different breakpoints were compared. Isolates with high-level rifampicin resistance were subjected to whole-genome sequencing.RESULTS:
A wide distribution of MICs (mostly in the range 0.125-8â mg/L) was observed for rifampicin, rifapentine, and rifaximin. Using MIC >1, ≥ 4, and > 4â mg/L as the breakpoints, resistance rates to rifampicin/rifapentine/rifaximin were 60.4%/48.3%/38.2%, 28.1%/25.8%/23.6%, and 15.7%/16.9%/7.9%, respectively. However, the rifabutin MICs of all the tested H. pylori isolates were extremely low (≤0.016â mg/L). Applying MIC ≥ 0.125â mg/L as the breakpoint, rifabutin resistance was nil. No mutation was found in the rpoB gene sequences of the 2 isolates with high-level rifampicin resistance.CONCLUSIONS:
There is a lack of cross-resistance between rifabutin and other rifamycins in H. pylori. The use of rifampicin E-test to predict H. pylori rifabutin resistance is inappropriate.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Helicobacter pylori
/
Rifabutin
Type of study:
Prognostic_studies
/
Risk_factors_studies
Language:
En
Journal:
J Infect Dis
Year:
2022
Document type:
Article
Affiliation country: