H pylori 'test and treat' should be offered to patients with un-investigated dyspepsia, says NICE. It recommends two types of testing for H pylori €“ a carbon-13 (13C) urea breath test or a stool antigen test.1

It does not recommend 'office-based' blood testing (eg using finger-prick test kits) as results may not be conclusive. If the kit is testing for antibodies, these will persist and test positive even if H pylori has been eradicated. However, lab testing of blood samples can be used where performance has been locally validated.1,17

The breath test involves a patient collecting a breath sample after fasting for several hours, ideally overnight. The first sample gives a baseline reading. The patient then swallows the 13C test solution. Another breath sample is collected after 30 minutes, and the breath samples are sent off for laboratory analysis with results sent to the patient's GP. The analysis tests for H pylori urease acting on the 13C-urea, releasing carbon dioxide and ammonia. The 13C-labelled CO2 is absorbed into the bloodstream and exhaled.26

If a patient has been using a PPI or antibiotics, there should be at least a two week 'wash out' period before an initial testing for H pylori with a breath test or the stool antigen test. Similarly, wait a month after H pylori eradication treatment before doing a retest.1,17