Pervasive occult gastrointestinal bleeding in an Alaska native population with prevalent iron deficiency: role of Helicobacter pylori gastritis

Chronic gastrointestinal infection with the bacterium Helicobacter pylori may be responsible for the chronic iron deficiency seen in many Alaska natives. Researchers studying the Yupik eskimos found that many had anemia even though their diet is rich in iron. In a detailed study of 140 adults, 90% had blood in their stool. Among 70 who had endoscopy, 97% had evidence of severe Helicobacter pylori infection that caused ulcers and hemorrhages. They also had evidence of gastritis, which is an inflammation of the stomach. This could account for their gastrointestinal bleeding.
Objective.--To confirm prevalent iron deficiency among Yupik Eskimos living in Alaska and to explore the frequency of and potential lesions accounting for occult gastrointestinal bleeding. Design.--Descriptive survey. Setting.--Rural Arctic community. Subjects.--A total of 140 adult volunteers from 3 villages in the Yukon-Kuskokwim Delta region of western Alaska. Main Outcome Measures.--Daily iron intake, hematologic and biochemical indexes of iron status, fecal hemoglobin levels, stool parasites, and endoscopic findings. Results.--While dietary iron intake by Yupiks was similar to that of a reference population, iron deficiency prevalence was increased 13-fold in Yupik men and 4-fold in Yupik women. Fecal hemoglobin levels were elevated in 90% of subjects contrasted with only 4% of a reference group; median levels were 5.9 and 0.5 mg of hemoglobin per gram of stool, respectively. Among 70 Yupik subjects with elevated fecal hemoglobin levels who had endoscopy performed, 68. (97%) had an abnormal gastric appearance consisting of erythema, mucosal thickening, diffuse mucosal hemorrhages, erosions, or ulcerations. Gastric biopsies revealed chronic active gastritis with associated Helicobacter pylori in 68 (99%) of 69. No other hemorrhagic gastrointestinal disease was detected. Conclusions.--Based on this study sample, occult gastrointestinal bleeding appears to be pervasive in the Yupik population and likely underlies the prevalent iron deficiency. An atypical hemorrhagic gastritis associated with H pylori infection is present almost universally and may represent the bleeding source. JAMA. 1997;277:1135-1139