S1655 Increased Prevalence of Achlorhydria With Age in an Asian Population: Should We Be Screening for Achlorhydria in Patients Aged 50 and over: 22 Years Experience From a Large Hospital

Abstract

Introduction: Achlorhydria (AC) is a state in which the stomach is unable to produce hydrochloric acid. AC can be categorized as either permanent or temporary based on its causes. It can lead to several conditions including pernicious anemia (PA) which can cause irreversible neurological deficits. Diagnostic techniques of AC can be easily performed during esophagogastroduodenoscopy (EGD) by staining Congo red on the gastric mucosa. Methods: This analysis involved a large single center retrospective study aimed at determining the prevalence of AC in Thailand among EGD patients. Results: A total of 3,597 patients underwent EGD including Congo red staining method at the Vichaiyut Hospital from January 2010 to December 2019; 223 ones were excluded due to concurrent use of proton pump inhibitors. Results revealed that 18 from 3,374 patients (0.53%) had AC. Seven presented with permanent AC (5F, 2M) (median age = 69 years; range 58-92; Table). All 7 patients were found to have high levels of serum gastrin (mean = 2,485 pg/ml; S.D. = 689 pg/ml) and were pathologically confirmed with intestinal metaplasia. All 7 patients with permanent AC were found only when they were over 55 years old. Among 11 patients with temporary AC (5M, 6F: mean age 73.4 years; SD = 13.2 years), all had gastrointestinal Helicobacter pylori bacterial infection after being examined. After successful treatment for H. pylori and re- examination with Congo red, AC was absent among patients with temporary AC. All 11 patients with temporary AC were found only when they were over 45 years old. If counting only patients over 45 years of age, the prevalence of AC was 0.68% (18/2,614). No adverse events arising from Congo red occurred (Figure). Conclusion: Achlorhydria (AC) is relatively rare. Permanent and temporary AC were found only when they were over 55 and 45 years old, respectively. Staining Congo red on gastric mucosa can be safely and routinely incorporated into the EGD procedure for early detection of AC. We recommended a low-cost screening test such as serum vitamin B levels for screening only in patients aged 50 and over.Figure 1.: Congo red changes its color from red to dark blue or black in an acidic environment. Table 1. - Characteristics of patients with permanent AC Patients’s number Age (years) Serum Vitamin B12 (pg/mL)(normal value = 187-883 pg/mL) Anti-Intrinsic factor Serum gastrin level (pg/mL) 1 58 2000 Positive 2000 2 86 2000 Positive 3000 3 69 405 Positive 3000 4 69 224 Negative 1300 5 80 1642 Positive 3000 6 92 265 Positive 3000 7 68 100 Negative 2100