[Helicobacter pylori erradication and its relation to antibiotic resistance and CYP2C19 status].
OBJECTIVE
to assess the efficacy of rabeprazole (RPZ), amoxicillin (Am), and clarithromycin (Cla) (7 vs. 14 days) in the eradication of H. pylori, and to determine the effect of strain-specific antibiotic resistance and host CYP2C19 status.


METHODS
first, we determined the CYP2C19 status of 100 healthy subjects to establish a sample size for the clinical trial. Then, 59 H. pylori-infected patients were randomized to receive RPZ (20 mg daily) plus Cla (500 mg b.d.) and Am (1,000 mg b.d.) for 7 vs. 14 days. The MIC for Am and Cla were determined using the agar dilution method. The CYP2C19 genotype was determined by the PCR-RFLP method.


RESULTS
In the per-protocol analysis (PP) eradication rates were 89.7 and 72% for the 7- and 14-day groups (p = 0.159). In the intention to-treat analysis (ITT) eradication rates were 86.7 and 62.1% in the 7- and 14-day groups, respectively (p = 0.06). None of the strains was resistant to Am, and 4 strains were resistant to Cla: 3 (11.1%) in the 14-day group and 1 (4%) in the 7-day group. Neither strain-specific antibiotic resistance nor host CYP2C19 status influenced eradication rates.


CONCLUSIONS
both 7- and 14-day therapies were effective for H. pylori eradication. Strain resistance and CYP2C19 status do not seem to influence eradication rates in the studied population.
Garza González
E
E
Departamento de Microbiología. Facultad de Medicina, Universidad Autónoma de Nuevo León, México.
Giasi González
E
E
Martínez Vázquez
M A
MA
Pérez Pérez
G I
GI
González
G M
GM
Maldonado Garza
H J
HJ
Bosques Padilla
F J
FJ
D053799:2-Pyridinylmethylsulfinylbenzimidazoles / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D000328:Adult; D000658:Amoxicillin / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D000897:Anti-Ulcer Agents / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D001189:Aryl Hydrocarbon Hydroxylases / Q000235:genetics; D017291:Clarithromycin / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D065731:Cytochrome P-450 CYP2C19; D003627:Data Interpretation, Statistical; D024881:Drug Resistance, Bacterial; D004359:Drug Therapy, Combination; D005260:Female; D005838:Genotype; D016481:Helicobacter Infections / Q000188:drug therapy*; D016480:Helicobacter pylori / Q000187:drug effects; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D006899:Mixed Function Oxygenases / Q000235:genetics; D064750:Rabeprazole; D013997:Time Factors
D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D000900:Anti-Bacterial Agents; D000897:Anti-Ulcer Agents; D064750:Rabeprazole; D000658:Amoxicillin; D006899:Mixed Function Oxygenases; D001189:Aryl Hydrocarbon Hydroxylases; C045793:CYP2C19 protein, human; D065731:Cytochrome P-450 CYP2C19; D017291:Clarithromycin