A hematologist's view of unexplained iron deficiency anemia in males: impact of Helicobacter pylori eradication.

BACKGROUND AND OBJECTIVES: Helicobacter pylori infection with, or without coexisting autoimmune gastritis has been implicated in several recent studies as an important cause of IDA in patients with unexplained iron deficiency anemia (IDA). However, the role of H. pylori in the causation of IDA is still unsettled as the vast majority of reported patients were premenopausal women in whom menstrual blood loss was likely the dominant factor determining IDA.

DESIGN AND METHODS: Prospective study of 44 consecutive male IDA patients referred for hematologic evaluation. Following standard endoscopic studies, all patients were screened for non-bleeding GI conditions including celiac disease, autoimmune gastritis and H. pylori gastritis. All subject with H. pylori infection were offered triple therapy for H. pylori eradication.

RESULTS: Only 15 patients had a likely source of blood loss identified. The 29 males with "unexplained" IDA were distinguished by their younger age (36+/-20 vs. 57+/-17 years p<0.001), poor initial response to oral iron treatment, and high prevalence of H. pylori infection (25 of 29 vs. 5 of 15 p<0.0001) with (10) or without (15) coexistent autoimmune gastritis. Three had celiac disease. Following H. pylori eradication, all patients achieved normal hemoglobin levels with follow-up periods ranging from 4 to 69 months (38+/-15 months mean+/-1SD). This was accompanied by a significant decrease in H. pylori IgG antibodies and serum gastrin. Sixteen patients discontinued iron treatment, maintaining normal hemoglobin and ferritin and may be considered cured. Remarkably, 4 of the 16 achieved normal hemoglobin without ever having received oral iron after H. pylori eradication.

INTERPRETATION AND CONCLUSIONS: The favorable long-term clinical results of H. pylori eradication offer strong evidence for a cause-and-effect relation between H. pylori and IDA. Recognition of the respective roles of H. pylori and autoimmune gastritis in the pathogenesis of iron deficiency may have a strong impact on the clinical management of unexplained and refractory iron deficiency anemia.