Incidence of iron deficiency anemia in patients with large diaphragmatic hernia. A controlled study.

The incidence of anemia in 259 patients with a diaphragmatic hernia large enough to be seen on a routine chest roentgenogram was compared with that in 259 age- and sex-matched controls. Eighteen patients with diaphragmatic hernia were anemic, compared to one control subject (P less than 0.001). In thirteen patients with diaphragmatic hernia and in one control the anemia was proven to be caused by iron deficiency. The findings provide additional evidence that a large diaphragmatic hernia can cause anemia secondary to chronic gastrointestinal blood loss, which is usually not the result of reflux esophagitis.