hypochlorhydriaachlorhydria

Hypochlorhydriaachlorhydria is not a widely standardized term but may be used to describe a spectrum of reduced to absent gastric acid production. Hypochlorhydria denotes lower-than-normal gastric acid output; achlorhydria denotes near absence of hydrochloric acid in the stomach. Together, they indicate persistently elevated gastric pH that can impair digestion and defense against ingested pathogens.

Normal stomach acid activates pepsin, aids iron and vitamin B12 absorption, and helps control gastric microbial populations. When acid production falls, protein digestion is less efficient, and deficiencies in B12 and iron can develop with longer-lasting effects. Patients may experience symptoms such as indigestion, bloating, and early satiety, though symptoms are nonspecific.

Common causes include autoimmune gastritis with loss of parietal cells (pernicious anemia), chronic Helicobacter pylori infection, aging, and long-term use of acid-suppressing medications such as proton pump inhibitors or H2 blockers. Gastric surgery, gastric atrophy, and nutritional deficiencies can also contribute. Hypochlorhydria can be transient, while achlorhydria implies more sustained impairment.

Diagnosis relies on gastric pH testing or secretagogue tests, endoscopy with biopsy, and laboratory evaluation showing elevated serum gastrin and nutrient deficiencies (notably B12 and iron). Autoimmune gastritis carries a higher risk of gastric cancer and neuroendocrine tumors due to mucosal atrophy and intestinal metaplasia.

Management focuses on treating the underlying cause, correcting deficiencies with vitamin B12 and iron as needed, and monitoring for complications. Continued avoidance of exacerbating acid suppression is typically advised; any consideration of acid-replacement therapy should be guided by a clinician, as inappropriate use can cause harm. Regular follow-up is recommended.