title: Cure of refractory duodenal ulcer and infection caused by Helicobacter pylori by high doses of omeprazole and amoxicillin in a homozygous CYP2C19 extensive metabolizer patient.
abstract: A 53-year old female patient with duodenal ulcer and Helicobacter pylori infection was treated three times with a proton pump inhibitor-based triple therapy, such as lansoprazole-clarithromycin-amoxicillin (INN, amoxicilline) and lansoprazole-minocycline-cefaclor. However, the H pylori infection was not cured. A culture test revealed that her infection was a clarithromycin-resistant but amoxicillin-sensitive strain of H pylori. Moreover, a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis revealed that she was a homozygous extensive metabolizer of cytochrome P450 (CYP) 2C19 (wt/wt). The usual dose of the proton pump inhibitor was therefore assumed to be insufficient for her and then she was treated with a high dose of omeprazole (120 mg/day) and amoxicillin (2,250 mg/day) for 2 weeks. The H pylori infection and the ulcer lesion were then cured. One of the factors associated with success or failure of cure of H pylori infection by the proton pump inhibitor-based triple therapy appeared to be CYP2C19 genotype status. Dual treatment with a sufficient dose of a proton pump inhibitor plus amoxicillin could cure H pylori infection even after the failure to cure H pylori infection by a usual proton pump inhibitor-based triple therapy in patients with the wt/wt homozygous extensive metabolizer genotype of CYP2C19.
authors.affiliation: First Department of Medicine, Hamamatsu University School of Medicine, Japan. furuta@akiha.hama-med.ac.jp
authors.forename: T
authors.initials: T
authors.lastname: Furuta
authors.forename: M
authors.initials: M
authors.lastname: Takashima
authors.forename: N
authors.initials: N
authors.lastname: Shirai
authors.forename: F
authors.initials: F
authors.lastname: Xiao
authors.forename: H
authors.initials: H
authors.lastname: Hanai
authors.forename: K
authors.initials: K
authors.lastname: Ohashi
authors.forename: T
authors.initials: T
authors.lastname: Ishizaki
mesh_terms: D000658:Amoxicillin / Q000008:administration & dosage / Q000627:therapeutic use*; D000897:Anti-Ulcer Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001189:Aryl Hydrocarbon Hydroxylases; D065731:Cytochrome P-450 CYP2C19; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics*; D004359:Drug Therapy, Combination; D004381:Duodenal Ulcer / Q000188:drug therapy* / Q000235:genetics / Q000382:microbiology / Q000473:pathology; D004384:Duodenoscopy; D004791:Enzyme Inhibitors / Q000008:administration & dosage / Q000627:therapeutic use*; D005260:Female; D016481:Helicobacter Infections / Q000150:complications / Q000188:drug therapy* / Q000235:genetics / Q000473:pathology; D016480:Helicobacter pylori; D006720:Homozygote; D006801:Humans; D008875:Middle Aged; D006899:Mixed Function Oxygenases / Q000235:genetics*; D009853:Omeprazole / Q000008:administration & dosage / Q000627:therapeutic use*; D010406:Penicillins / Q000008:administration & dosage / Q000627:therapeutic use*; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D012008:Recurrence; D016896:Treatment Outcome
chemical_list: D000897:Anti-Ulcer Agents; D004791:Enzyme Inhibitors; D010406:Penicillins; D000658:Amoxicillin; D003577:Cytochrome P-450 Enzyme System; D006899:Mixed Function Oxygenases; D001189:Aryl Hydrocarbon Hydroxylases; C045793:CYP2C19 protein, human; D065731:Cytochrome P-450 CYP2C19; D009853:Omeprazole