Confounding Presentation of Small Bowel Ischemia in an IBS Patient and Diagnosis and Treatment Utilizing CO2 Angiography: New None-nephrotoxic Diagnostic Modality

Abstract

Introduction: Mesenteric ischemia is a difficult diagnosis to make but should be considered in older patients with weight loss. Since, CKD is a common comorbidity in patients with vascular disease contrast agents may contraindicated. CO2 angiography is a non-nephrotoxic alternative to vascular intervention. Case: The patient is a 90 year old female with a 40 year history of functional dyspepsia and IBS - diarrhea. 1 year PTA (prior to admission) she began noting vague post-prandial epigastric discomfort relieved with belching and probiotics. 9 months PTA, she noted early satiety and nausea following greasy food ingestion resulting in decrease intake and a 20lbs weight loss. Malignancy work-up (EGD, colonoscopy, CT abdomen/pelvis without contrast because of ↓ GFR, standard lab work) were negative except for marked atherosclerosis of the aorta and a small benign antral ulcer. She was treated with PPI and sucralfate. 7 months PTA, repeat EGD revealed another, small clean based antral ulcer at a different site with negative histology. She had now lost 40 lbs. with a BMI of 20. She attributed her weight loss to severe siderophobia as her postprandial epigastric pain occurred 20 minutes following meals with an intensity of 7-9/10, lasting 2-3 hours. She was also noted to have a retinal artery occlusion possibly 2nd to an atheromatous plaque which alerted us to the possibility of mesenteric ischemia. PE: Significant abdominal bruit. A CTA or MRA could not be performed because of her CKD.Figure 1Figure 2She was referred to vascular surgery who performed a Doppler US noting a >70 % stenosis of the SMA. Because of her CKD, she underwent CO2 angiography which identified a 90-99% stenosis of the SMA. After 6 hours, the SMA was catheterized and a stent was placed across the stenosis resulting in >50% flow. She had immediate and complete symptom relief. After 6 months, she had gained 20 lbs. Discussion: Mesenteric ischemia can present insidiously at first with vague, non-specific symptoms. When this is combined with a history of well-established functional GI disease, further delay in diagnosis can occur. Therefore, a high suspicion for the diagnosis of mesenteric ischemia is necessary and any new symptoms in a functional disease patient should be followed closely. For patients with CKD, CO2 angiography with digital subtraction angiography (DSA) is a preferred alternative to contrast angiography for treatment of mesenteric ischemia. This technique, which is relatively unknown to radiologists, is a therapeutic advance which few gastroenterologists recognize. It is a new armamentarium that can be used in older patients with poor kidney function. Further discussion and Illustrations of CO2 angiography will accompany the abstract.