Although guidelines exist for H. pylori test selection in the setting of dyspepsia, order volumes at a national reference laboratory (ARUP Laboratories) suggest that many physicians order less accurate (but less expensive) tests than what has been recommended; therefore, we analyzed the potential economic impact of these practices.

Methods:

We compared four testing strategies: 1) IgG, 2) IgG and IgA, 3) fecal antigen, 4) urease breath testing, and 5) IgG followed by fecal antigen confirmation. In addition, we included the possibility that PPI therapy may be administered prior to testing, which is the recommended course of action in areas of low prevalence for H. pylori. We used Markov chain Monte Carlo (MCMC) simulation modelling. Testing costs and direct medical costs were tracked along with cure rates. The possibility of a gastro-duodenal endoscopy and possible biopsy after unsuccessful relief of dyspeptic symptoms were also modeled.

Results:

The most inexpensive treatment/diagnosis route is to begin with empiric PPI therapy, followed by a fecal antigen test to assess infection status if symptoms continue (mean = $211, SD = $139). The most expensive route is empiric PPI Therapy followed by IgG and IgA serology if the patient remains symptomatic (mean = $578, SD = $368). Its expense may be due to the low sensitivity and specificity of these tests. This result is most significant as the serological tests are the most frequently ordered and of the least diagnostic value. False negatives from these tests can result in continued symptoms due to inappropriate treatment and additional diagnostic tests to conclusively determine the cause of the symptoms. Upon sensitivity analysis, the cost of the gastro-duodenal endoscopy (range = $400-$1000) had the heaviest influence on model outcome.

Conclusions:

Many physicians may be basing treatment for h. pylori infection on outdated serological tests. The fecal antigen detection test appears to be excellent in both diagnostic value and cost. The breath test has may have best diagnostic value, but at a premium cost. The great cost of endoscopy and its associated morbidity relative to the diagnostic tests that may inadvertently lead to the procedure emphasize the importance of avoiding unnecessary endoscopies. The use of the fecal antigen or breath tests may decrease the rate of unnecessary endoscopy and / or biopsy.