Hey team!
I am writing to share a high-value care pearl this week from the Things We Do For No Reason (TWDFNR) series! For those who haven’t read before, the Journal of Hospital Medicine’s TWDFNR series was inspired by ABIM’s Choosing Wisely Campaign and highlights practices that have become common in medicine but don’t necessarily add value for our patients.
This week, we will focus on serologic testing for H. pylori. Here are some highlights from an article by Xu and Graham, published 7/2021 in JHM.
-The preferred noninvasive diagnostic tests for H. pylori are the urea breath test and the stool antigen test (both are send-out and have a turn-around time of 2-6 days). For patients who get an endoscopy, histopathologic testing is also a preferred diagnostic method.
-Serologic testing is cheap, immediate, and convenient. However, the main drawback is that it cannot distinguish between active and prior infection, reducing its specificity.
-Why you might think serologic testing is helpful: Patients admitted for a GI bleed from peptic ulcer disease are appropriately started on PPIs in the hospital. PPIs, bismuth, and antimicrobials can all reduce the sensitivity of biopsy and stool and urea breath tests, but do not affect serologic testing.
However, there is no evidence that an immediate diagnosis of H. pylori improves patient outcomes. Many can safely complete a course of PPI therapy and be re-tested as an outpatient 4 weeks after completion of PPI therapy.
-Situations where serologic testing can be acceptable: high clinical pre-test probability – peptic ulcer disease on endoscopy without other risk factors who have reasons to have a potentially false-negative biopsy result (MALT lymphoma, treatment with PPIs/bismuth/antimicrobials, active ulcer bleeding during endoscopy). A positive serologic test here (provided they have not been positive before on testing) may prompt empiric initiation of eradication therapy. This may be especially helpful if you have concerns about a patient’s ability to follow-up.
-If you pursue serologic testing, only the IgG should be used. The IgA and IgM assays are available but are not FDA-approved and have poor diagnostic performance.
References:
https://www.journalofhospitalmedicine.com/jhospmed/article/243002/hospital-medicine/things-we-do-no-reasontm-serum-serologic-helicobacter?channel=27621
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4864555/