Differential Diagnosis for Bleeding per Rectum post Aortic Aneurysm Repair
- Single most likely diagnosis
- Aortoenteric fistula: This is a serious and potentially life-threatening complication that can occur after aortic aneurysm repair. It involves the formation of a fistula (an abnormal connection) between the aorta and the intestine, which can lead to severe bleeding. The presentation of bleeding per rectum post-aortic aneurysm repair makes this a highly likely diagnosis.
- Other Likely diagnoses
- Ischemic colitis: This condition occurs when there is a reduction in blood flow to the colon, which can happen after aortic aneurysm repair due to the manipulation of blood vessels or emboli. Ischemic colitis can cause bleeding, pain, and other symptoms, making it a plausible cause for bleeding per rectum in this scenario.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Graft infection: Although less common, infection of the graft used in the aortic aneurysm repair can lead to severe complications, including fistula formation, sepsis, and death. Early detection and treatment are crucial, making this a "do not miss" diagnosis.
- Colon perforation: This is a rare but potentially fatal complication that could occur due to the surgical procedure itself or as a result of ischemia. Prompt recognition and intervention are necessary to prevent severe outcomes.
- Rare diagnoses
- Hemorrhagic colitis due to other causes: Other rare causes of hemorrhagic colitis, such as infectious colitis or inflammatory bowel disease exacerbation, could potentially present with similar symptoms but are less directly related to the aortic aneurysm repair itself.
- Angiodysplasia or other vascular malformations: These are rare conditions that could cause gastrointestinal bleeding but are not typically associated with aortic aneurysm repair. They would be considered if other more common causes are ruled out.