The role of video capsule endoscopy in the evaluation of iron deficiency anaemia.

It is widely accepted that chronic occult blood loss from the gastrointestinal tract is a major cause of iron deficiency anaemia. Endoscopists are often asked to evaluate iron deficiency anaemia and identify the source of bleeding. This review offers an effective diagnostic strategy for this common clinical problem. After investigating the normal upper and lower parts of the gastrointestinal tract, the source of bleeding remains unidentified in about 10% of patients. The existing guidelines for evaluation of iron deficiency anaemia in patients above the age of 45, who have undergone standard upper and lower gastrointestinal examinations, are limited to a "treat and observe" phase. Small bowel X-ray series fail to detect many mucosal lesions, particularly vascular ectasias. While enteroscopy offers direct visual inspection of the small bowel mucosa beyond the reach of the standard upper endoscopes, this instrument reaches only 80-120 cm beyond the ligament of Treitz and its sensitivity in identifying the source of bleeding varies (24-75% of patients). A new and conceptually simple approach to examining the entire small intestine is video capsule endoscopy of the small bowel. This review addresses the optimal role of video capsule endoscopy in iron deficiency anaemia patients and offers guidelines for the appropriate gastrointestinal evaluation in such patients.