High prevalence of atrophic body gastritis in patients with unexplained microcytic and macrocytic anemia - A prospective screening study

OBJECTIVE: Atrophic body gastritis (ABG) is characterized by atrophy of the gastric body mucosa, hypergastrinemia, and hypo/achlorhydria. Its associat ion with pernicious anemia is well recognized. Gastric hypo/achlorhydria is known to affect iron absorption but ABG is rarely considered as a possible cause of iron deficiency (microcytic) anemia. The aims of this study were to validate a screening methodology for the detection of ABG in a consecuti ve series of patients with microcytic and macrocytic anemia and to investig ate the clinical and gastric morphofunctional characteristics of the two he matological presentations of ABG. METHODS: A two-part prospective study was carried out. Part A aimed to vali date the screening methodology to detect the presence of ABG in patients wi th macrocytic and microcytic anemia who have no specific GI symptoms, by me asuring their gastrin levels and verified by performing gastroscopy with bi opsy. Part B aimed to detect the presence of ABG in a larger sample of anem ic patients by our validated method and, by pooling the data of ABC patient s, to determine the clinical, gastric histological, and functional characte ristics pertaining to the macrocytic and microcytic presentations of ABG. RESULTS: In part A, ABG was detected in 37.5% of patients with macrocytic a nd in 19.5% of those with microcytic anemia. Pooling the data of the ABG pa tients from part A and part B, microcytic ABG patients were on average 20 y r younger than those with macrocytic anemia. The majority of microcytic ABG patients were female, most of whom were premenopausal. H. pylori infection was widely represented in the microcytic ABG group (61.1%). They also had a lesser grade of body mucosal atrophy and lower hypergastrinemia levels, s uggesting a less severe oxyntic damage of shorter duration. CONCLUSIONS: Macrocytic anemia is not the only hematological presentation o f ABG. Physicians evaluating patients with unexplained iron deficiency anem ia should consider ABG as a possible cause by determining fasting gastrin l evels and performing gastroscopy with biopsies of the body mucosa. (Am J Ga strocnterol 1999;94:766-772, (C) 1999 by Am. Coll. of Gastroenterology).