Reply to Prof. Dorta’s Editorial

Abstract

We are grateful to Prof. Dorta for his critical appraisal of the gas− troscopic breath test (GBT) [1,2]. However, we do not agree to major points in the criticisms raised in the editorial.GBT should not be misunderstood as a new principle for detect− ing Helicobacter pylori infection. The aim of the study was to de− scribe the feasibility of a progressive, validated, and noninvasive technique for 13 C−urea breath testing using continuous molecular correlation spectroscopy, providing real−time results, in a new clinical setting ± i. e., during gastroscopy.We are aware that in the study presented, strict criteria for con− traindications to biopsy sampling were applied, including treat− ment with nonsteroidal anti−inflammatory drugs (NSAIDs). However, the two most recent recommendations from the Amer− ican Society for Gastrointestinal Endoscopy (ASGE) are hardly evidence−based expert opinions, as they are based on very lim− ited published data [3,4]. In clinical reality, the use of aspirin, NSAIDs, and warfarin has been associated with significant upper and lower gastrointestinal bleeding [5 ± 11], and many gastroen− terologists would avoid taking biopsies in patients taking these medications. We agree that the risk of bleeding after biopsy may be relatively small, but the use of GBT for H. pylori testing can eliminate this avoidable risk in the large population under− going endoscopy.Most patients with an indication for H. pylori detection will in any case initially undergo an upper gastrointestinal endoscopy examination to evaluate related mucosal lesions; the test de− scribed by our group was designed for this group of patients alone. Thus, there is no additional risk of gastroscopy at all. In ad− dition, the very small risk involved in diagnostic gastroscopy needs to be distinguished from the risks of H. pylori testing. On the other hand, gastroscopic breath testing will certainly not be used in patients who have already undergone endoscopic evalu− ation. The use of GBT therefore does not mean replacing a simple breath test with a gastroscopic procedure; instead, it combines two standard diagnostic tests that can be clinically performed si− multaneously.Furthermore, there are no reasons to expect that the validity of the breath test will be significantly altered by concomitant oxy− gen therapy, which is often administered during gastroscopy un− der conscious sedation. Since the detection of H. pylori is based on the 12 C/ 13 C ratio in the breath, not on the concentration of CO 2 , we do not think that supplemental oxygen therapy during gastroscopy might be capable of affecting the results of the breath test. In addition, there are no data suggesting that H. py− lori urease activity might be sensitive to inhaled oxygen to any clinically relevant extent.It was not the aim of this feasibility study to provide an extensive economic analysis. This would require a larger number of patients and outcome data, which were both clearly beyond the scope of this study. However, the costs per test were included and compar− e...