Fecal Occult Blood Testing
Based on aggregate data from recent reports, the majority of pathologic occult GI bleeding arises from the upper GI tract….nearly twice as often as from the lower GI tract. Any lesion that involves vascular disruption can bleed, and the potential specific causes of occult bleeding are legion. By general category, these can be inflammatory (the most common cause of iron deficiency anemia in adults is peptic ulcer or erosive disease), traumatic (which may account for up to 10% of iron deficiency in older adults, primarily from large hiatal hernias). The picture here shows linear erosions caused by respiratory or diaphragmatic trauma within a hiatal hernia, vascular (there are many types of vascular malformations, and they are often multiple), and finally, neoplastic (cancers invade mucosal vessels and cause bleeding, such as might occur with this colorectal cancer shown in the image).
Causes of Occult GI Bleeding
Jump to section:
- Occult Gastrointestinal (GI) Bleeding: Definition
- Quantity of GI Bleeding Required to "See" Blood in Stool
- Fecal Occult Blood Tests
- Why Detect Occult GI Bleeding?
- Causes of Fe Deficiency in Industrialized Countries (Average %)
- Causes of Occult GI Bleeding
- Fecal Detection of Ingested Blood
- Iron Deficiency or Anemia: Which Test?
- CRC Screening: Target Lesions
- Occult Bleeding From Colorectal Cancer
- Fecal Blood Testing for Colorectal Cancer (CRC)
- FOBT Screening
- Stool Test Detection of CRN in Screen Setting
- Laboratory Testing vs Office Digital Rectal Exam (DRE)
- Evaluation of Fecal Immunochemical Testing (FIT) Assays
- FIT Specificity
- CRC Screening by FOBTs
- CRC Screening Guidelines*
- CRC Screening: Which Fecal Blood Test?
- Soft Indications for FOBT Use?
- Fecal Occult Blood Tests Summary
- Mayo Medical Laboratories Tests