**13. Role of** *H. pylori* **vaccine**

Efforts to develop a vaccine against *H. pylori* have had little success over the last three decades. However, a large phase 3 clinical trial in China of an oral vaccine containing urease B has shown over 70% protection against infection. Nevertheless, the vaccine is not yet available, and more data is required before it can be widely used [1].

### **14. Follow-up**

After treatment, it is important to assess the success or failure of the treatment. The optimal testing time depends on the choice of treatment and the test used. However, it is generally recommended to retest after four weeks of stopping antibiotics and two weeks after discontinuing PPI therapy. Various methods, both invasive and non-invasive, can be used for retesting, including the UBT, stool antigen test, and endoscopy [16]. According to the ACG, UBT or stool antigen test should be performed to confirm the eradication of *H. pylori* [16]. Endoscopy is indicated after treatment of *H. pylori* infection in two conditions: complicated PUD and gastric ulcer. The most common complications of PUD are bleeding, perforation, and obstruction/stenosis, which require either endoscopy/surgery for initial management. Non-invasive methods

#### *Current Perspective on the Treatment of* Helicobacter pylori *Infection DOI: http://dx.doi.org/10.5772/intechopen.114135*

cannot be used in these cases because patients should be on a prolonged course of PPI, thus endoscopy is usually done to confirm eradication after treatment [16].

Gastric ulcer carries the risk of underlying malignancy, and therefore retesting with endoscopy and biopsy is necessary following eradication [16]. This not only confirms the eradication status with absolute certainty but also allows for the assessment of any underlying risk of malignancy by obtaining a biopsy from the margin of the ulcer. In cases of gastric ulcer, both before and after treatment biopsy is indicated to exclude malignancy [16]. However, in places where advanced endoscopy with new imaging techniques is available, if an ulcer appears benign with regular margins, repeat endoscopy after eradication may not be necessary [16]. Endoscopy is indicated after eradication in conditions such as for surveillance of premalignant lesions, early gastric cancer, familial gastric cancer, and gastric MALT lymphoma. The frequency of surveillance depends on the underlying conditions [16].
