SEROLOGY TO MONITOR THE EFFICACY OF ANTI-HELICOBACTER-PYLORI TREATMENT

Objective: To assess the usefulness of monitoring anti-Helicobacter py lori antibodies to judge the efficacy of anti-Helicobacter treatment. Patients and methods: Twelve patients in whom eradication of H. pylori by triple therapy failed were compared with 24 successfully treated p atients, matched for age, sex, diagnosis and time lag between the star t of treatment and the second serum sample. Anti-H. pylori IgC antibod ies were measured using a commercial enzyme-linked immunosorbent assay before and 3-4 months after treatment. Results: Antibody titres decre ased by 25-78% in 22 out of 23 successfully treated patients with a pr etreatment antibody titre above the cut-off point. The antibody titre decreased in only two out of the nine evaluable patients in whom eradi cation failed. Kolmogorov-Smirnov test results were consistent with a normal distribution of the decrease in the natural logarithm of antibo dy titres. Based on these data, a 40% decrease in the antibody titre 3 -4 months after treatment confirms eradication with almost 100% specif icity and 75% sensitivity.Conclusion: When the pretreatment antibody t itre is above the cut-off level, a decrease in this titre 3-4 months a fter treatment can be used to monitor the efficacy of anti-H. pylori t reatment.