title: Factors associated with treatment failure of Helicobacter pylori infection in a developing country.
abstract: BACKGROUND
  Although no regimen can eradicate in 100% of patients, factors that may affect the eradication rates have been poorly studied.
  
  
  OBJECTIVE
  To evaluate factors associated with treatment failure.
  
  
  METHODS
  One hundred patients were treated with pantoprazole plus clarithromycin and furazolidone for eradication. Clarithromycin and furazolidone resistance was evaluated by the agar dilution method. Point mutations in 23S rRNA genes related to clarithromycin resistance were investigated by polymerase chain reaction and restriction length fragment polymorphism and A by polymerase chain reaction. The data were analyzed by logistic regression.
  
  
  RESULTS
  eradication occurred in 85 of 97 patients who completed the treatment (87.6%; 95% CI = 79.0-93.1). All strains were susceptible to furazolidone, and nine were resistant to clarithromycin (A2142G or A2143G mutation was detected in all of them). The treatment failure was significant and independently associated with clarithromycin resistance (OR = 7.79; 95% CI = 1.73-35.01), A-negative status (OR = 4.81; 95% CI = 1.14-20.14), and male gender (OR = 4.20; 95% CI = 1.01-17.78), but not with the type of disease, mean age, smoking, alcohol consumption, and the degree of the antral and oxyntic gastritis.
  
  
  CONCLUSIONS
  Resistance to clarithromycin, A-negative status, and gender were predictive factors of eradication failure.
mesh_terms: D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D000293:Adolescent; D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D000891:Anti-Infective Agents, Local / Q000008:administration & dosage / Q000627:therapeutic use*; D000897:Anti-Ulcer Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001562:Benzimidazoles / Q000008:administration & dosage / Q000627:therapeutic use*; D017291:Clarithromycin / Q000008:administration & dosage / Q000627:therapeutic use*; D003906:Developing Countries; D024881:Drug Resistance, Bacterial; D004359:Drug Therapy, Combination; D005260:Female; D005664:Furazolidone / Q000008:administration & dosage / Q000627:therapeutic use*; D016481:Helicobacter Infections / Q000188:drug therapy*; D016480:Helicobacter pylori / Q000187:drug effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009853:Omeprazole / Q000031:analogs & derivatives; D000077402:Pantoprazole; D012307:Risk Factors; D012737:Sex Factors; D013454:Sulfoxides / Q000008:administration & dosage / Q000627:therapeutic use*; D017211:Treatment Failure
chemical_list: D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D000900:Anti-Bacterial Agents; D000891:Anti-Infective Agents, Local; D000897:Anti-Ulcer Agents; D001562:Benzimidazoles; D013454:Sulfoxides; D005664:Furazolidone; D000077402:Pantoprazole; D017291:Clarithromycin; D009853:Omeprazole