Cross-sectional GI Imaging Should Precede Capsule Endoscopy in Evaluation of Overt-Obscure GI Bleeding With Negative Endoscopic Work-up

Abstract

A 54 year old female with GERD on daily omeprazole presented with 2 days of maroon stools which progressed to melena. She denied abdominal pain, hematemesis, or NSAID use. Physical exam was notable for stable vital signs, benign abdomen, and rectal exam with black stool positive for occult blood. Her hemoglobin was 8.2g/dL, decreased from 12 a week earlier, and BUN was 21mg/dL. She was started on IV pantoprazole and EGD revealed a few small fundic gland polyps, but no blood or ulcers. Colonoscopy revealed hematin scattered throughout the entire colon and distal terminal ileum. The patient continued to have melena and was referred for CT enterography (CTE). A 4.1 x 4.8 x 4.7 cm hypervascular mass was seen arising from the wall of the terminal ileum with large feeding vessels from the superior mesenteric artery. She underwent exploratory laparotomy with excision of an isolated mass and resection of 14cm small bowel. Pathology demonstrated a submucosal lesion without hemorrhage or necrosis with normal overlying mucosa; high-power exam showed bland spindle shaped cells with varying degrees of eosinophilic cytoplasm arranged in fascicles. Mitoses numbered < 2 per 50 high power fields. A c-kit (CD117) stain was positive, confirming the diagnosis of low-grade GIST. This case illustrates an example of active, overt-obscure GI bleeding (OGIB) diagnosed by CTE following negative colonoscopy and EGD. In this setting, guidelines favor proceeding to capsule endoscopy (CE) as a first-line diagnostic tool for evaluation of the small bowel. The few prospective studies directly comparing diagnostic yield of CTE vs CE for OGIB are conflicting, as sensitivity is influenced by lesioncharacteristics and timing of exam, among other factors. In this patient who was unable to receive a CE in the hospital, CTE presented a safe, noninvasive initial step towards an expedient diagnosis. Most guidelines incorporate both CE and CTE after negative colonoscopy and endoscopy. With overt-obscure bleeding, we believe CTE may be superior given its widespread availability and ability to detect masses and bleeding lesions. Further prospective studies are needed to elucidate the optimal approach. In the meantime, we as endoscopists evaluating GI bleeding should think beyond just endoscopic approaches and consider CTE in the appropriate setting.Figure 1