Factors associated with treatment failure of Helicobacter pylori infection in a developing country.

Background: Although no regimen can eradicate in 100% of patients, factors that may affect the eradication rates have been poorly studied.

Goal: To evaluate factors associated with treatment failure.

Study: 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.

Conclusion: Resistance to clarithromycin, A-negative status, and gender were predictive factors of eradication failure.