A positive C14 breath test is considered to be a case of H. pylori infection, as the C14 breath test is the main clinical test for H. pylori. H. pylori has a strong binding capacity to C14, so this characteristic can be used to detect the presence of this bacterial infection in the body. The procedure is to swallow a drug containing a C14 marker before performing the C14 breath test, wait a few moments for the H. pylori to bind to the C14 marker, and then perform the breath test with a C14 breathalyzer. indicates the presence of H. pylori infection in the body.