Achlorhydria Differential Diagnoses

Updated: Mar 05, 2019
  • Author: Divyanshoo Rai Kohli, MD; Chief Editor: BS Anand, MD  more...
  • Print

Diagnostic Considerations

Important considerations

Long-term proton pump inhibitor (PPI) therapy has been associated with two major complications. As described previously, there is an association with hip fractures in patients with achlorhydria on PPI therapy. In addition, the current use of gastric acid suppressive therapy has been associated with an increased risk of community-acquired pneumonia (CAP).

Sustained achlorhydria has been observed after PPI treatment in a patient with Zollinger-Ellison syndrome (ZES), starting soon after treatment began and becoming complete within 6 months.

Gastric resection, leading to surgically induced achlorhydria, has been associated with severe postoperative infections. It has been observed in humans that the lack of an acidic environment may favor bacterial overgrowth. This, in turn, can lead to various nutrient deficiencies with significant clinical manifestations.

According to a study from the Netherlands by Janssen et al, patients with achlorhydria who take nonsteroidal anti-inflammatory drugs (NSAIDs) develop upper gastrointestinal ulcers during NSAID use in a similar fashion as patients who produce acid normally. [17]

Drug-induced achlorhydria is a particularly important condition in elderly patients, in whom it may be associated with secondary bacterial overgrowth.

Patients with pernicious anemia and achlorhydria may demonstrate impaired absorption of iron and may be screened for iron deficiency.

Differential Diagnoses