Abstracts [2576] Figure 3. Terminal ileum biopsy showing small bowel mucosa with chronic active inflammation, crypt architectural distortion, colonic crypts containing eosinophils and neutrophils. [2577] Figure 3. Push enteroscopy identifying an oozing mass, found in the jejunum, that was consistent with peritoneal mesothelioma. [2577] Figure 1. CT displaying a lymph node inseparable from a loop of proximal small bowel measuring 7.3 3 2.4 cm; correlating with an intensely FDG avid lymph node on PET/CT in image 2. [2578] [2577] Figure 2. PET/CT showing FDG avidity of the small bowel. 2578 Meckel’s Diverticulum: A Diverticulum Like No Other Mira Alsheikh, MD1, Fady Haddad, MD2, Stephen Mulrooney, MD3. 1 2 Staten Island University Hospital, Staten Island, NY; Northwell Health Staten Island University 3 Hospital, Staten Island, NY; Staten Island University Hospital, Northwell Health, Staten Island, NY. INTRODUCTION: Meckel’s diverticulum (MD) is a relatively uncommon cause of gastrointestinal (GI) bleeding in adults. “Often looked for and seldom found,” MD is challenging to diagnose despite the various imaging modalities available. Herein, we present the case of a young man who presented with lower GI hemorrhage and negative endoscopy, bleeding scan, and angiography. Meckel’s diverticulum was later diagnosed via scintigraphy scan. We review the noninvasive diagnostic imaging for Meckel’s diverticulum, mainly technetium-99m (Tc 99m) pertechnetate scan, and bleeding scan. © 2019 by The American College of Gastroenterology Figure 1. Meckel’s diverticulum, macroscopic view. CASE DESCRIPTION/METHODS: A 26-year-old man presented with multiple episodes of melena. He had acute onset anemia. Workup, including upper endoscopy, colonoscopy, and push enteroscopy were not able to identify the site of bleeding even after repeat procedures. A computed tomography scan with intravenous contrast and mesenteric angiography were also unrevealing. A Technetium 99m bleeding scan was read as negative. Persistent bleeding necessitated recurrent transfusions. Capsule endoscopy was deployed. A Meckel’s scan (Tc 99m Pertechnetate scan) revealed an abnormal focus of uptake in the right lower abdomen suggesting the diagnosis of Meckel’s diverticulum. The patient underwent laparoscopic resection of the diverticulum and was discharged home (Figures 1 and 2). A retrospective review of the bleeding scan revealed isolated uptake in the location of the Meckel’s Diverticulum. Review of the capsule endoscopy revealed a diverticulum in the small bowel in the right lower quadrant without active bleeding (Figure 3). DISCUSSION: Bleeding Meckel’s diverticulum is easier to diagnose than MD presenting with other symptoms, but still an outstanding challenge. High suspicion for MD should be sought in the evaluation of a young patient presenting with GI bleeding; the gold standard for diagnosis is the technetium-99m pertechnetate scan or so-called Meckel’s scan. Bleeding scan is another noninvasive imaging modality that helps to detect a bleeding MD. Although both scans use Tc 99m, the mechanism is different. Meckel’s scan uses Tc 99m, which is secreted by parietal cells in the mucus, thus detecting gastric cells within MD. On the other hand, the bleeding scan works via identifying Tc 99m that is bound to hemoglobin, therefore identifying a bleeding MD. Both scans are noninvasive and safe. The use of either one should be tailored according to the clinical presentation. The American Journal of GASTROENTEROLOGY Copyright © 2019 by The American College of Gastroenterology. Unauthorized reproduction of this article is prohibited. S1417 S1418 Abstracts decreasing the absorption of fat-soluble vitamins K & Vitamin D. The parathyroids release more PTH in an attempt to maintain serum calcium levels through increasing osteoclastic activity. Other mechanisms active in celiac disease also increases bone resorption (See Figure 2). Bisphosphonates are a standard treatment for preventing osteoporotic fractures, by reducing osteoclastic activity. In this patient with active celiac disease, with low availability of dietary calcium, this resulted in hypocalcemia. This can be mitigated with closer observation and adjustment of doses of vitamin D and calcium supplementation when administering bisphosphonates. 2580 Nothing but NET: A Case of Neuroendocrine Tumor in the Duodenal Bulb Michelle Baliss, DO1, Mohammad Bilal, MD1, Sheharyar Merwat, MD2. 2 The University of Texas Medical Branch, Galveston, TX; University of Texas Medical Branch, Galveston, TX. 1 [2578] Figure 2. Microscopic examination with hematoxylin-eosin stain shows the margin of Meckel’s diverticulum with the normal intestinal mucosa. Notice the ectopic gastric mucosa with mucous and parietal cells. INTRODUCTION: Neuroendocrine tumors (NETs) are rare neoplasms that comprise approximately 2% of all malignant tumors in the gastrointestinal system. The ileum remains the most common site of NETs in the small intestine, making up .70% of small bowel NETs. Duodenal NETs are exceedingly rare, comprising 2-3% of all gastrointestinal NETs and 1-3% of all duodenal tumors. We present a rare case of a patient diagnosed with a duodenal bulb NET. CASE DESCRIPTION/METHODS: A 66-year-old male with a past history of gastroesophageal reflux disease and hypertension presented to the gastroenterology clinic with a chief complaint of intermittent halitosis for the past year. The symptoms were unrelated to food intake. His recent dental examination was normal. He did not have a family history of gastrointestinal malignancies. His physical examination was unremarkable. Laboratory data including Helicobacter pylori antigen was unremarkable. He underwent esophagogastroduodenoscopy which demonstrated a 15 mm nodule in the duodenal bulb (Figure 1). Histopathological examination of the nodule showed a welldifferentiated neuroendocrine tumor. Neuroendocrine immunohistochemical stains were positive for chromogranin and synaptophysin. Ki-67 was positive in 1% of tumor cells. CT scan of the abdomen revealed a 1.2 3 0.8 3 0.7 cm well-defined hyperattenuating structure in the posterior wall of the duodenal bulb (Figure 2). On endoscopic ultrasound, the lesion appeared to be located within the deep mucosa and submucosa without invasion of adjacent structures (Figure 3). The patient has been referred to medical oncology. DISCUSSION: The duodenum is an uncommon location for NETs. Duodenal NETs are typically small, single-lesion neoplasms, the majority of which are non-functional and diagnosed during the 6th decade of life. Unlike NETs of the jejunum and ileum that lack a gender preference, duodenal NETs carry a slight male predominance. Metastasis to regional lymph nodes is seen in ;60% of cases and to the liver in less than 10% of cases. The absence of neuroendocrine clinical syndromes in .90% of duodenal NETs coupled with the rarity of this malignancy creates a noteworthy diagnostic challenge. It is therefore not surprising that the majority of these cases are diagnosed incidentally during work-up for other symptoms. With a rising annual incidence of NETs, it is important for gastroenterologists to keep this diagnosis in mind as a differential for any nodule in the duodenum. 2581 Acute Lymphoblastic Leukemia Presenting With Mesenteric Ischemia [2578] Figure 3. Videocapsule endoscopy: Meckel diverticulum. 2579 Calcium Disorders in Celiac Disease Usman Naseer, MBBS1, Ali Wazir, MBBS1, Raina A. Patel, MD2, Haider Rahman, MD1, Jae Chung, DO1, Mackenzie LaPorte, MBA, BS3, Elise Malecki, MD, PhD3. 1 2 3 Albany Medical Center, Albany, NY; Stratton Veteran Affairs Medical Center, Albany, NY; Albany Medical College, Albany, NY. INTRODUCTION: Celiac disease is known to affect calcium homeostasis in various ways leading to osteoporosis and osteopenia. We present a case of active celiac disease complicated by hypocalcemia and osteoporosis. CASE DESCRIPTION/METHODS: The patient is a 74-year-old male with known Celiac disease diagnosed 25 years ago. He had known hypocalcemia with secondary hyperparathyroidism treated with calcium and calcitriol supplements to maintain calcium levels (Corrected Calcium: 8.5 mg/dl with PTH of 89 pg/ml and 25-hydroxy Vitamin D of 80 ng/ml). The patient had a mechanical fall, a few months ago and subsequent DEXA scan showed osteoporosis (Bone mineral density of L1-L4 vertebral bodies was 3.5 standard deviation below normal). The patient was treated with an infusion of zoledronic acid. A week later the patient presented with malabsorptive diarrhea likely due to reported non-compliance with a gluten-free diet. On admission labs, he was noted to have severe hypocalcemia (ionized 0.8, corrected calcium was 6.7). Of note, his PTH had increased to 385. Incidentally, his INR was also noted to be mildly elevated at 1.5. Despite this, he had no apparent symptoms of hypocalcemia. During the admission, the patient had an EGD and biopsies were done showing mucosal changes consistent with celiac disease confirming dietary non-adherence. Hypocalcemia was treated with IV infusion of Calcium and he was discharged on increased doses of Calcitriol and calcium supplements with close follow-up with endocrinology. DISCUSSION: Celiac disease affects the small intestine including duodenum, the primary site of absorption of divalent ions including calcium. The intraluminal dietary fats bind to this calcium The American Journal of GASTROENTEROLOGY Michelle Baliss, DO1, Timothy Krill, MD1, Hamza Abdulla, MD1, Sreeram Parupudi, MD, FACG2. 1 2 The University of Texas Medical Branch, Galveston, TX; University of Texas Medical Branch, Galveston, TX. INTRODUCTION: Acute lymphoblastic leukemia (ALL) is a malignancy of B/T-cell lymphoid precursors that predominantly affects the pediatric population. Presenting symptoms are usually related to bone marrow and organ infiltration. Arterial thrombosis is extremely rare and seldom seen as a presenting manifestation of acute leukemia. To our knowledge, we present the first case of mesenteric ischemia due to complete occlusion of the superior mesenteric artery (SMA) as the first manifestation of T-cell ALL. CASE DESCRIPTION/METHODS: A 44-year-old male presented with severe upper abdominal pain, vomiting and diarrhea for 1 day. Physical examination was notable for diffuse abdominal tenderness and pain out of proportion to exam. Initial laboratory data showed WBC of 2.02 3 103/mL with 30% blasts. Lactic acid was within normal limits. CT of the abdomen revealed a thrombus in the SMA resulting in complete occlusion (Figure 1). An emergent open SMA thrombectomy was performed following failure of catheter-directed thrombolysis. Diffuse ischemic changes were visualized in the jejunum necessitating a partial small bowel resection (Figure 2). Intraoperative transesophageal echocardiogram was negative for intracardiac thrombus or valvular pathology. A peripheral blood smear revealed a large population of immature cells with fine chromatin and a high nuclear to cytoplasmic ratio (Figure 3). Flow cytometry showed a large population of blasts constituting about 22% of cells, positive for CD5, CD7, and CD10. The immunophenotypic appearance confirmed the diagnosis of T-ALL. He was referred to medical oncology for bone marrow biopsy. DISCUSSION: This is the first reported case of acute arterial occlusion in the SMA leading to mesenteric ischemia as the initial manifestation of T-cell ALL. SMA thromboembolism typically occurs in the setting of atherosclerosis or cardiac pathology, which were absent in this case. Venous thromboembolism is a well-documented complication of acute leukemia that negatively impacts mortality. The inhibition of anticoagulant proteins, production of prothrombotic factors, alteration of the vascular endothelium, and increased vascular adhesion of leukemic cells are all potential contributors. However, arterial occlusion is extremely unusual and almost exclusively seen in acute promyelocytic leukemia (APL). This report illustrates that an unexplained arterial or venous thrombotic event in a previously healthy patient could be a sign of an underlying malignancy. VOLUME 00 | SUPPLEMENT | MONTH 2019 www.amjgastro.com Copyright © 2019 by The American College of Gastroenterology. Unauthorized reproduction of this article is prohibited.
