RESUMEN

A clinical trial was conducted in Argentina to determine the efficacy of clarithromycin plus lansoprazole for the treatment of Helicobacter pylori in duodenal ulcers and non-ulcer dyspepsia. PCR-RFLP was conducted on an 820-bp amplified product of the ureC gene of H. pylori to determine the genetic heterogeneity of 83 pretreatment and 21 post-treatment isolates. Twelve different restriction patterns were observed when digested with Sau 3A or Hha I, resulting in 40 different RFLP types. Comparison of isolates before treatment to after treatment showed that 20 of 20 patients had the same RFLP type. In addition, the presence of the cytotoxin-associated gene (cagA) and the vacuolating gene (vacA) were determined. All pretreatment isolates were positive for vacA whereas 75% of the pretreatment isolates were positive for cagA. The results of this study indicate that a high degree of heterogeneity exists among H. pylori and that infection is not limited to a small number of RFLP types.

Asunto(s)

Antibacterianos/uso terapéutico , Antígenos Bacterianos , Proteínas Bacterianas/efectos de los fármacos , Proteínas Bacterianas/genética , Claritromicina/uso terapéutico , Genes Bacterianos/efectos de los fármacos , Infecciones por Helicobacter/microbiología , Helicobacter pylori/clasificación , Helicobacter pylori/genética , Inhibidores de la Síntesis de la Proteína/uso terapéutico , Gastropatías/microbiología , Proteínas Bacterianas/biosíntesis , Biopsia , Sondas de ADN , Infecciones por Helicobacter/tratamiento farmacológico , Humanos , Reacción en Cadena de la Polimerasa/métodos , Polimorfismo de Longitud del Fragmento de Restricción , Reproducibilidad de los Resultados , Serotipificación/métodos , Gastropatías/tratamiento farmacológico