Small Bowel Arteriovenous Malformations Research Articles

Challenges in Identifying and Resecting Small Bowel Arteriovenous Malformation

Challenges in Identifying and Resecting Small Bowel Arteriovenous Malformation

Intestinal arteriovenous malformations: a diagnostic and therapeutic challenge

Arteriovenous malformations (AVM) of the intestine are rare causes of gastrointestinal bleeding. Diagnosis depends upon accurate interpretation of imaging features and histopathology to differentiate them from other vascular malformations. Presentation of colonic AVM with mucous diarrhea and pain is rare and poses diagnostic challenges. Usually, patients presenting with bleed need surgical intervention. The current report discussed one patient with chronic liver disease, extrahepatic portal vein thrombosis with small bowel AVM and two patients with colonic AVM, highlighting management strategies adopted.

S2872 A Case of CMV Enteritis Resulting in Severe Obscure GI Bleeding

INTRODUCTION: Small bowel (SB) bleeding accounts for less than 5% of gastrointestinal (GI) bleeds, in non-IBD patients, with an even smaller portion originating from the jejunum [1]. Locating SB bleeds poses great challenges, frequently resulting in delay in diagnosis. Although SB arteriovenous malformations (AVMs) are most common, other rare etiologies such as infectious enteritis should be considered. CASE DESCRIPTION/METHODS: A 62 year old male was diagnosed with T-cell lymphoma with EBV positivity and placed on high-dose steroids for one month. Staging CT chest, abdomen, and pelvis incidentally revealed intraperitoneal free air with concerns for a gastric wall neoplasm. EGD revealed a 4cm, deep, non-bleeding, non-perforated ulcer in the gastric body (Image 1). Two weeks after, he had painless melanotic stools, requiring multiple transfusions. Emergent arteriography of the celiac and mesenteric arteries did not identify a source of bleeding. Repeat CT imaging was negative for worsening free air. His course continued to worsen, requiring high-dose vasopressors and continued transfusions. Emergent EGD and colonoscopy were performed. EGD revealed a known, non-bleeding gastric ulcer. Colonoscopy showed bright red blood to the cecum with scattered, non-bleeding, ischemic-appearing ulcers (Image 2). Repeat celiac angiogram was performed two more times, eventually revealing active bleeding from small jejunal artery branches which were embolized. Due to concern for ongoing bleeding, surgical resection of the distal jejunum and proximal ileum was performed. Gross pathology demonstrated extensive ulcerations, with biopsies negative for malignancy (Image 3). Serum testing for Cytomegalovirus (CMV) was positive for strongly elevated quantitative levels and the patient was started on Valganciclovir. DISCUSSION: Delays in diagnosing SB bleeds are not uncommon and can frequently be fatal. Our case presents a complex diagnostic scenario where bleeding was presumed to be from the known gastric lesion, but complicated by inability to perform EGD safely with pneumoperitoneum. Ultimately, the patient’s immunocompromised state and steroids predisposed him to opportunistic infections such as CMV, resulting in bleeding ulcers in the jejunum and ileum. Upon literature review, CMV enteritis is exceedingly rare and accounts for under 5% of all CMV infections in the GI tract [2]. Though rare, CMV enteritis has been reported to cause massive hemorrhage requiring emergent surgery and is often associated with high mortality.Figure 1.: 4cm non-bleeding ulcer in the gastric body seen on the initial EGD.Figure 2.: Scattered ischemic-appearing colonic ulcers.Figure 3.: Gross specimen of resected and ulcerated jejunum.

1950 An Unexpectedly Large Vascular Anomaly Causing Chronic Obscure GI Hemorrhage: A Case Report

INTRODUCTION: Approximately 5–10% of patients who present with an acute gastrointestinal (GI) hemorrhage have a primary small bowel source. While small bowel angioectasias are one of the most common causes of small bowel hemorrhage, it is rare to find large vascular anomalies in the small bowel as a cause of chronic GI bleed. CASE DESCRIPTION/METHODS: We present a case of a 56-year-old woman referred to our institution for management of obscure GI bleeding, associated with severe iron deficiency anemia. She had intermittent melena and occasional dark red blood mixed with stool. Extensive work up in an outside facility including 2 endoscopies, 2 colonoscopies, and a capsule endoscopy were unrevealing. After referral to our institution; push enteroscopy, colonoscopy and retrograde single balloon enteroscopy were performed and were negative for source of bleeding. Capsule endoscopy revealed a small oozing angioectasia in proximal jejunum. The lesion was treated with heater probe via anterograde single-balloon enteroscopy. Due to persistent melena and anemia, antegrade balloon enteroscopy was repeated and demonstrated an abnormal cluster of vascular-appearing lesions in the proximal jejunum that were marked with two hemostatic clips. CT angiogram was consistent with a large arteriovenous malformation (AVM). Interventional radiology performed glue embolization of the high-flow jejunal arteriovenous malformation. The post procedure course was complicated by ischemic proximal jejunum which was confirmed on repeat enteroscopy. Fortunately, her symptoms completely resolved with conservative management without surgical intervention. DISCUSSION: AVMs are abnormal lesions with a direct connection between the arterial and venous blood supply without any true capillary bed connecting them. While extremely rare within the GI tract, they can cause significant amount of bleeding and must be considered in patients with obscure GI bleeding or chronic iron deficiency anemia. Studies have shown that AVMs typically only account for 1–2% of upper GI bleeds. More common sites for AVMs include the cecum and ascending colon, while other sites like the small bowel are much more rare. Diagnostic work up typically begins with upper endoscopy followed by colonoscopy. However, these tests are often unrevealing when dealing with small bowel AVMs. Patient’s typically undergo capsule endoscopy for further evaluation, as seen in our patient. If the source of bleeding is still un-identified, then angiography or bleeding scans may be required.

2003 Extragastric Dieulafoy’s Lesion: A Rare and Often Missed Cause of Upper Gastrointestinal Bleeding

INTRODUCTION: Dieulafoy’s lesions (DL) are an important, potentially life threatening, cause of gastrointestinal (GI) bleeding. Dieulafoy’s lesions are dilated, aberrant, submucosal arteries that erode overlying GI mucosa in the absence of an underlying ulcer, aneurysm, or intrinsic mural abnormality. They account for approximately 1.5% of acute upper GI bleeding and 70% of these lesions are found within 6 cm of the gastroesophageal junction. Although uncommon, DL have been reported in the duodenum, distal stomach, and esophagus. We present a case describing the discovery and management of an extragastric DL within the duodenum. CASE DESCRIPTION/METHODS: An 83-year-old male with multiple comorbidities, on warfarin therapy, presented to the hospital by instruction of his primary care physician for evaluation of a low hemoglobin (Hgb). He has a history of chronic anemia with regularly monitored Hgb. The patient endorsed 4 days of painless, dark, loose stools. He reported a similar episode to this several years prior and underwent upper and lower endoscopy, which were unrevealing. Capsule endoscopy at that time did show a small bowel arteriovenous malformation, but otherwise unremarkable. On admission, the patient was hemodynamically stable with mild pallor noted on exam. Initial workup revealed Hgb of 6.8 g/dL and an INR of 3.1. Upper endoscopy was performed revealing a single spurting spot of active bleeding in the second part of the duodenum consistent with a DL. The area was successfully treated with epinephrine, coagulation, and hemostatic clips. He remained hospitalized for five days post-procedure for medical optimization. His Hgb remained stable and his warfarin was resumed. DISCUSSION: Dieulafoy’s lesions are a rare cause of upper GI bleeding that should always remain on the differential diagnosis. While gastric DL are well-known, there are few reports describing DL of the duodenum. The scarce nature of their occurrence make these lesions difficult to diagnose. Thorough endoscopic evaluation is usually the first diagnostic test performed for acute upper GI bleeding. Thus, this is the primary modality used for the diagnosis of DL. Initial EGD is diagnostic in only about 70% of cases due to relatively small lesion size, intermittently active bleeding, and lesion location. This case represents a patient with acute on chronic anemia that had previously undergone a thorough investigation with few answers. Serial Hgb monitoring and follow-up endoscopy led to the discovery and treatment of his duodenal DL.

Diagnosis and therapeutic strategies for small bowel vascular lesions.

Small bowel vascular lesions, including angioectasia (AE), Dieulafoy’s lesion (DL) and arteriovenous malformation (AVM), are the most common causes of obscure gastrointestinal bleeding. Since AE are considered to be venous lesions, they usually manifest as a chronic, well-compensated condition. Subsequent to video capsule endoscopy, deep enteroscopy can be applied to control active bleeding or to improve anemia necessitating blood transfusion. Despite the initial treatment efficacy of argon plasma coagulation (APC), many patients experience re-bleeding, probably because of recurrent or missed AEs. Pharmacological treatments can be considered for patients who have not responded well to other types of treatment or in whom endoscopy is contraindicated. Meanwhile, a conservative approach with iron supplementation remains an option for patients with mild anemia. DL and AVM are considered to be arterial lesions; therefore, these lesions frequently cause acute life-threatening hemorrhage. Mechanical hemostasis using endoclips is recommended to treat DLs, considering the high re-bleeding rate after primary APC cauterization. Meanwhile, most small bowel AVMs are large and susceptible to re-bleeding therefore, they usually require surgical resection. To achieve optimal diagnostic and therapeutic approaches for each type of small bowel lesion, the differences in their epidemiology, pathology and clinical presentation must be understood.

Diagnostic yield of capsule endoscopy for small bowel arteriovenous malformations in patients with hereditary hemorrhagic telangiectasia: a systematic review and meta-analysis.

Background and study aims Small bowel arteriovenous malformations (AVMs) pose a bleeding risk and have traditionally been diagnosed by invasive enteroscopic procedures in patients with hereditary hemorrhagic telangiectasia (HHT). Capsule endoscopy (CE) is emerging as a safe and non-invasive alternative for small intestinal evaluation, but its diagnostic yield and utility in diagnosing small bowel AVMs in HHT patients are understudied. The aim of this study was to meta-analyze the utility of CE for diagnosing AVMs in HHT patients. Methods A meta-analysis and systematic review of the literature on CE in HHT patients identified in the PubMed, EMBASE, Scopus, and Cochrane databases from inception to March 2018 were conducted. Summary effects were estimated using a random effects model. Results After applying exclusion criteria, five studies (n = 124 patients) were eligible for meta-analysis. The pooled diagnostic yield for visualization of small bowel AVMs by CE was 77.0 % (95 % CI 65.8 – 85.4 %, P < 0.001). Conclusions CE has a good diagnostic yield for small bowel AVMs in HHT. It can be regarded as a sufficient, noninvasive diagnostic modality for identifying small bowel AVMs in HHT patients.

(1357) - The Role of Beta Blockers in the Prevention of Gastrointestinal Bleeding After Left Ventricular Assist Device Implantation

Gastrointestinal bleeding (GIB) affects between 15 to 30% of LVAD recipients. Small bowel arteriovenous malformations (AVM) have been implicated in about one-third of GIB events. It is believed that LVADs reduce pulse pressure that triggers an increase in sympathetic tone, causing smooth-muscle relaxation, arteriovenous dilation and AVM. This mechanism of AVM is also seen in patients with advanced liver disease and portal hypertension. Beta-blockers cause splanchnic vasoconstriction reducing portal and collateral blood flow. Hence, we sought to determine the role of beta-blockers in reducing the incidence of GIB in LVAD recipients.

Use and Misuse of Small Bowel Video Capsule Endoscopy in Clinical Practice

Video capsule endoscopy (VCE) was introduced into the United States in 2000 and has significantly advanced the ability to visualize the small intestinal mucosa by using noninvasive technology. Compared with traditional imaging with small bowel barium imaging, the use of VCE has demonstrated the ability to enhance diagnostic yield in patients with suspected small bowel pathology by approximately 25%‐50% in patients with suspected small bowel disorders. 1‐3 Although the use of VCE has been recommended as the next step in patients with obscure gastrointestinal hemorrhage after a negative upper and/or lower endoscopic examination, 4 its use in other clinical scenarios such as small bowel inflammatory disorders may not be associated with similar diagnostic yields. The major complication associated with the use of VCE remains small bowel retention. Although the risk of this event is virtually nil in patients with obscure bleeding, it can approach 10% in patients with known inflammatory bowel disease (IBD). 5 A critical appraisement of appropriate use of this technology may help physicians and third-party payers to determine which subset of patients with suspected or known small bowel disorders would benefit the most from undergoing a VCE procedure. To critically examine the use of VCE in clinical practice, an evidence-based approach was performed by using the GRADE system, 6,7 and a critical review of the literature on capsule endoscopy was performed by using PubMed, SCOPUS, and the Cochrane Database from 2000‐2012. The quality of evidence could range from high (implying that further research was unlikely to change the authors’ confidence in the estimate of the effect) to moderate (further research would be likely to have an impact on the confidence in the estimate of effect) or low (further research would be expected to have an important impact on the confidence in the estimate of the effect and would be likely to change the estimate). The strength of a recommendation was graded as strong when the desirable effects of an intervention clearly outweigh the undesirable effects and as conditional when there was uncertainty about the tradeoffs. The evidence-based statements generated from this review are shown in Table 1. Studies including more than 20 patients were included for each topic to increase data quality when metaanalyses or randomized controlled trials were not available.

Successful treatment with thalidomide of a patient with congenital factor V deficiency and factor V inhibitor with recurrent gastrointestinal bleeding from small bowel arteriovenous malformations

Successful treatment with thalidomide of a patient with congenital factor V deficiency and factor V inhibitor with recurrent gastrointestinal bleeding from small bowel arteriovenous malformations

Allosensitization in Cardiac Transplantation

Allosensitization in Cardiac Transplantation

Adult extracorporeal membrane oxygenation and gastrointestinal bleeding from small bowel arteriovenous malformations: A novel treatment using spiral enteroscopy

Adult extracorporeal membrane oxygenation and gastrointestinal bleeding from small bowel arteriovenous malformations: A novel treatment using spiral enteroscopy

A Case of Small Bowel Arteriovenous Malformation with Intestinal Obstruction

A Case of Small Bowel Arteriovenous Malformation with Intestinal Obstruction

N-Butyl Cyanoacrylate Embolization of Small Bowel Arteriovenous Malformation Presenting with Acute Massive Lower Gastrointestinal Hemorrhage

A 58 year-old man presented to our emergency department with acute-onset bleeding from the rectum. On arrival, his systolic blood pressure was 80 mm Hg. Findings of physical examination were unremarkable except for pallor. His presenting hemoglobin level was 13.0 g/dL and hematocrit level was 37.4%. The patient's medical history was unremarkable for significant other comorbid conditions. The emergency department course was complicated by unresolved, massive rectal bleeding that resulted in transfusion of 12 units of blood and two units of platelets along with crystalloid solution.

Application of Wireless Capsule Endoscopy for the Evaluation of Iron Deficiency Anemia in Patients With Ileal Pouches

Although wireless capsule endoscopy (WCE) is widely used in the assessment of small bowel pathology, its application in patients with ileal pouches has not been evaluated. Persistent anemia has been observed in patients with ileal pouches, for which identification of etiology can be challenging. To assess the utility of WCE in ileal pouch patients with persistent anemia in conjunction with other diagnostic modalities. Ulcerative colitis patients with persistent anemia (hemoglobin <10 g/dL) at least 12 months after either ileal pouch-anal anastomosis or continent ileostomy surgery were studied. Esophagogastroduodenoscopy, pouch endoscopy, WCE, and celiac disease serology were studied. The final diagnosis of the etiology of anemia was based on the results from the combined assessment of clinical, endoscopic, histologic, and laboratory data. Seventeen ileal pouch patients (10 females, 7 males) with underlying inflammatory bowel disease were studied with a mean age 42.1+/-15.2 years. Nine patients (52.9%) had active pouchitis and 3 (17.6%) had Crohn's disease (CD). WCE was successfully completed in 16 patients (94.1%). Suspected causes of anemia were identified in 5 patients (29.4%): 2 patients with CD of the pouch and 1 patient with celiac disease, detected by esophagogastroduodenoscopy, pouch endoscopy, small bowel biopsy, and celiac disease serology, and 1 patient with CD of the small bowel and 1 patient with small bowel arterio-venous malformations shown on WCE only. WCE seemed to be feasible and well tolerated in patients with ileal pouches. WCE provided additional diagnostic information in the pouch patients with anemia.

Evolution from Primary Biliary Cirrhosis to Primary Biliary Cirrhosis/Autoimmune Hepatitis Overlap Syndrome

An asymptomatic 70-year-old Hispanic woman with type 2 diabetes was found in 2004 to have an AST of 132 U/L, ALT 146 U/L, alkaline phosphatase 1107 U/L, total serum bilirubin 3.5 mg/dL, and albumin 2.9 g/dL. Viral hepatitis testing was negative. Serum IgG, IgA, and IgM were all elevated, antimitochondrial antibody was weakly positive, and antinuclear antibody was negative. Liver biopsy was reported to show "evolving cirrhosis with marked lymphoid hyperplasia." Although the indication was nowhere stated, she was prescribed ursodeoxycholic acid 500 mg b.i.d, on which her biochemical tests initially improved. One year later she developed itching and jaundice. Imaging studies revealed multiple gallstones. An MRCP was suggestive of cirrhosis with a questionable common bile duct stricture, and she underwent ERCP with removal of gallbladder and common bile duct stones and placement of a biliary stent. A periampullary mass, which proved to be a somatostatinoma, was excised in 2006 via an open laparotomy, at which the stent was removed and a second liver biopsy performed. It was reported as showing chronic active hepatitis, activity stage 2, and fibrosis grade 3 with bridging. Her subsequent course was complicated by recurrent bleeding from small bowel arteriovenous malformations. Seen for the first time at Columbia University Medical Center in January 2007, she complained of continuing pruritus. AST was 69 U/L, ALT 43 U/L, alkaline phosphatase 491 U/L, and total bilirubin 3.3 mg/dL. Serum albumin was 2.6 g/dL. Antinuclear antibodies, negative in 2004, were now positive at 1:320, and antimitochondrial M2 antibodies were strongly positive. Serum IgG and IgA, but NOT IgM, were elevated. Review of her outside liver biopsies revealed features of primary biliary cirrhosis (PBC) in the first, and of both PBC and autoimmune hepatitis (AIH) in the second. The patient exhibits an overlap syndrome, in which both histologic and serologic features of AIH evolved in a setting initially most suggestive of PBC alone. The phenomenon of autoimmune overlap syndromes is discussed.

DIC as a Complication of HHT or Osler-Weber-Rendu Syndrome

The possibility of disseminated intravascular coagulopathy (DIC) as a complication of hereditary hemorrhagic telangectasia (HHT) has been described in the past[1]. However, due to the low incidence of HHT, information on the topic is scarce. We present a case of HHT complicated by DIC to support the clinical awareness needed with regards to DIC resulting in bleeding as a presentation of HHT. A 72 year old female presented with a severe episode of epistaxis and was found to be in DIC. She had been suffering from recurrent episodes of epistaxis for over 5 years. Her past medical history included pulmonary embolus, COPD, hypertension and diverticulosis. Her family history included recurrent epistaxis in her father and son. Physical examination on presentation demonstrated a telangectetic lesion on the tongue and fingertips and dried blood in her right nares. Laboratory data revealed WBC 7.67, HCT 37, MCV 86.2, Platelets 114, PT 24, INR 2.1, Fibrinogen < 70, and DDimer >5250. BUN 8, Cr 0.8. Endoscopy performed for hematemesis confirmed gastric arterio-venous malformations (AVMs). CT angio of abdomen and chest demonstrated pulmonary, liver, and gastrointestinal tract AVMs. Small bowel capsule study confirmed gastric AVMs with no small bowel AVMs. Genetic testing demonstrates single nucleotid (A) deletion at position 364 of the ALK-1 gene causing a truncated ALK-1 protein. A clinical diagnosis of HHT was confirmed. This case adds to the literature in support of the clinical relevance of DIC as a complication of HHT. Furthermore, in this case it was a part of the acute presentation which led to the diagnosis of HHT. [1] Ann N Y Acad Sci, 1981;370:851–4

Cost-Benefit Analysis of Double Balloon Enteroscopy Compared to Other Diagnostic Modalities for Obscure Gastrointestinal Hemorrhage

Background: Double balloon enteroscopy (DBE) is a new technology that allows for non-surgical exploration in patients with obscure bleeding. We created a decision analysis to determine the cost-effectiveness of initial DBE compared to capsule endoscopy (CE), push enteroscopy, intraoperative enteroscopy, or angiography for the diagnosis and management of small bowel arteriovenous malformations (AVMs). Methods: We created a decision tree (TreeAge Pro 2005, TreeAge, MA) to compare costs and outcomes for patients with transfusion-dependent obscure occult bleeding. The base case was no treatment. Competing alternative strategies included push enteroscopy, intraoperative enteroscopy, CE followed by DBE if a lesion was detected, angiography, and DBE. DBE was initiated using the oral approach, followed by the rectal approach if no lesion was found. Patients with unsuccessful treatment were assumed to have ongoing transfusion requirements of 4 units/month. We calculated that there would be a spontaneous cessation rate for AVM-related hemorrhage of 22% per year. We assumed that the probability of detecting an AVM on CE would be 67% (Triester Am J Gastro 2005) with a probability of finding an AVM on DBE of 60%. Procedural costs were obtained from the 2005 American Medical Association CPT website. Cost of CE was estimated at $1120, DBE oral approach $282, and DBE rectal approach $790. Costs of inpatient hospital services were obtained by using the 2004 Medicare Prospective Payment System DRG. The time horizon of the model was 1 year. Results: Baseline analysis results are shown in the Table. Initial oral DBE approach was the most effective strategy with an average cost-effectiveness ratio of $6000 per patient successfully treated compared to no therapy. Threshold values on sensitivity analysis that would lead to capsule-directed DBE as the preferred approach included a probability of AVM on oral DBE <59%, probability of AVM after capsule >66%, and probability of AVM on CE >69%. Intraoperative enteroscopy was preferred if the probability of success on oral DBE <54%. No other changes in probabilities or costs altered the model results. Conclusions: For patients with obscure occult bleeding from small bowel AVMs, initial DBE is a cost-effective approach.

Push enteroscopy in a UK district general hospital: experience of 51 cases over 2 years

To determine the number of patients referred for enteroscopy in a district general hospital (DGH), the indication, enteroscopic +/- histological diagnosis, and to compare findings with other series from tertiary referral centres or outside the UK. Retrospective case series over a 2-year period. In the 2-year period, 52 patients were referred for enteroscopy. All except one underwent enteroscopy. The mean age of the patients was 60 years (range 31-84 years). The main indications for enteroscopy were obscure gastrointestinal haemorrhage in 31 (61%) patients (19 with acute and 12 with chronic bleeding) and 7 (14%) patients with arteriovenous malformations (AVMs) on initial oesophagogastroduodenoscopy (OGD). Other indications included clinical deterioration in known coeliac disease in four (8%) patients and abnormal small-bowel follow-through in five (10%) patients. More than half (51%) of the enteroscopies were reported as abnormal, but 10 (38%) had pathology in the stomach or first part of the duodenum (D1) not diagnosed on initial OGD. Diagnoses of two T-cell lymphomas and one of pre-lymphomatous monoclonal T-cell proliferation were made in the refractory coeliac disease group. Indications (obscure gastrointestinal bleeding), most frequent findings (small-bowel AVMs), and 'missed' lesions within reach of a gastroscope (20%) were in keeping with other series. Enteroscopy is a useful tool in investigating patients with refractory coeliac disease. Its value in investigating patients with abnormal small-bowel radiology was not confirmed. The current need for push enteroscopy in a DGH is small (approximately 1 per 8000 population per year), but it would take only small changes in referral practice to escalate. Criteria for enteroscopy should be developed and refined with improving knowledge of the diagnostic yield for each indication and clinical outcome.

Small-bowel endoscopy.

An overview of the scientific literature on small-bowel enteroscopy demonstrates that sonde enteroscopy is becoming more and more limited in its indications. Push enteroscopy is now a well-accepted modality for evaluation of the patient with small-bowel disease, including those with undiagnosed causes for gastrointestinal bleeding, various types of malabsorption, and radiological abnormalities. Intraoperative enteroscopy has very specific indications, and there is a high rate of positive findings. It appears that an enterotomy with passage of a shorter, more maneuverable enteroscope is an acceptable way to evaluate the small bowel, although use of a sonde enteroscope may be an innovative method for intraoperative enteroscopy. In the evaluation of patients with iron-deficiency anemia or occult gastrointestinal bleeding in whom colonoscopy is negative, it is evidently more cost-effective to use a dedicated push enteroscope early on. The use of two different instruments--a gastroscope followed by a dedicated push enteroscope--is more expensive, and probably does not increase the yield for pathology. Many lesions that are responsible for obscure bleeding are actually located within reach of an upper intestinal endoscope, but are not recognized. This is probably due to inexperience on the part of the original endoscopist, who may see the pathology, but does not invoke it as the cause for bleeding. Outcome studies are now being performed, and there are some interesting considerations for combination hormonal therapy in patients with recurrent obscure bleeding, which most likely emanates from small-bowel arteriovenous malformations.