Metronidazole resistance and virulence factors in Helicobacter pylori as markers for treatment failure in a paediatric population.
The eradication rate obtained using the classical triple therapy containing metronidazole, amoxicillin and bismuth citrate, was determined in 57 paediatric patients with digestive disorders, according to the susceptibility to metronidazole of the Helicobacter pylori strains (determined by agar dilution) and the cagA and vacA status (determined by PCR). Eradication was obtained in 38 out of 43 patients (88.3%) infected by H. pylori with metronidazole MIC < or = 2 mg l(-1), in 3 out of 6 patients (50%) when MIC was 4-8 mg l(-1) and in 4 out of 8 patients (50%) when MIC was > 8 mg l(-1). Among patients infected with cagA+ and cagA- strains an eradication rate of 75% (6/8) and 75% (18/24) was found, and 50% (3/6) and 80% (21/26) among vacA s1- and vacA s2-infected subjects (P > 0.05). H. pylori eradication depends on the susceptibility of the strain to metronidazole, being higher in patients infected with susceptible H. pylori. However, according to our data the cagA or vacA status was not an important factor in treatment failure in the eradication of H. pylori.
López-Brea
M
M
Department of Clinical Microbiology, Hospital Universitario de la Princesa, Madrid, Spain.
Martínez
M J
MJ
Domingo
D
D
Sánchez
I
I
Alarcón
T
T
D000293:Adolescent; D000658:Amoxicillin / Q000627:therapeutic use; D000900:Anti-Bacterial Agents / Q000494:pharmacology* / Q000627:therapeutic use; D000897:Anti-Ulcer Agents / Q000627:therapeutic use; D000942:Antigens, Bacterial; D001426:Bacterial Proteins / Q000235:genetics; D002648:Child; D002675:Child, Preschool; D004352:Drug Resistance, Microbial; D004359:Drug Therapy, Combination; D016481:Helicobacter Infections / Q000188:drug therapy*; D016480:Helicobacter pylori / Q000187:drug effects* / Q000254:growth & development / Q000472:pathogenicity*; D006801:Humans; D008795:Metronidazole / Q000494:pharmacology* / Q000627:therapeutic use; D008826:Microbial Sensitivity Tests; D009942:Organometallic Compounds / Q000627:therapeutic use; D010406:Penicillins / Q000627:therapeutic use; D017211:Treatment Failure; D014774:Virulence / Q000235:genetics
D000900:Anti-Bacterial Agents; D000897:Anti-Ulcer Agents; D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D009942:Organometallic Compounds; D010406:Penicillins; C074689:VacA protein, Helicobacter pylori; C080866:cagA protein, Helicobacter pylori; D008795:Metronidazole; D000658:Amoxicillin; C002791:bismuth tripotassium dicitrate