Prospective Evaluation of Gastrointestinal Lesions by Bidirectional Endoscopy in Patients with Iron Deficiency Anemia
Supot Pongprasobchai MD*, Tassanee Sriprayoon MD*, Sathaporn Manatsathit MD*
Affiliation : *Division of Gastroenterology, Department of Internal Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
Background : Occult bleeding from the gastrointestinal (GI) lesions is a common cause of iron deficiency anemia (IDA). The
information concerning the prevalence and the appropriate strategy for evaluation of IDA in Thai patients is scanty.
Objective : Prospectively evaluate Thai patients with IDA for GI lesions using bidirectional endoscopy.
Material and Method: Consecutive patients with IDA were investigated by esophagogastroduodenoscopy (EGD) and
colonoscopy. Significant GI lesions were identified. Clinical data and results of the fecal occult blood testing (FOBT) were
collected to determine factors associated with the presence of GI lesions.
Results : One hundred three patients were included in this study and the mean age was 63.6 + 15.2 years old. Significant GI
lesions were detected in 58 patients (56%), 43% by EGD, 25% by colonoscopy. Twelve patients (12%) had dual lesions
identified from both EGD and colonoscopy. The most common lesions were peptic ulcers (22%) and colonic carcinoma
(13%). Anti-platelets use and positive FOBT were associated with the significant GI lesions with odds ratios of 2.37 (95% CI
1.05-5.36, p = 0.036) and 2.83 (95% CI 1.05-7.68, p = 0.038), respectively. FOBT had sensitivity, specificity, positive
predictive value, and negative predictive value for significant GI lesions at 81%, 40%, 68%, and 66%, respectively. Site-
specific symptoms correctly guided the route of endoscopy in 60-80% of the patients.
Conclusion : EGD resulted in a better yield than colonoscopy and was the preferred route of initial endoscopy unless there
was suggestive site-specific symptom. Bidirectional endoscopy was finally required in most patients unless a cancerous lesion
was detected by the initial endoscopy.
Keywords : Iron deficiency anemia, Bidirectional endoscopy, Esophagogastroduodenoscopy, Colonoscopy, Fecal occult blood test
