Long-term follow-up of Helicobacter pylori serology after successful eradication.

We conclude that a 20% decline in IgG concentration has an overall sensitivity of 93% for determining H. pylori eradication 12-21 months after H. pylori treatment. Serology is an attractive alternative to endoscopy or urea breath tests in monitoring patients after H. pylori treatment, but serum IgG levels should not be expected to reach seronegative range after successful H. pylori eradication.