Introduction: Juvenile Polyposis Syndrome (JPS) is an autosomal dominant condition in which hamartomatous polyps may form throughout the GI tract. Genetic markers associated with JPS are SMAD4 and BMPR1 of which there are several known clinically relevant mutations. Variants of undetermined significance (VUS) are often encountered in clinical practice, leading to diagnostic and management conundrums. We present a rare case of a patient with a variant of undetermined significance of SMAD4 presenting with a large gastric juvenile polyp. Case Description/Methods: A 32-year-old man with no past medical history was found to have iron deficiency anemia after presenting with fatigue and weight loss. Family history was significant for gastric adenocarcinoma in his mother. Initial workup showed negative celiac serologies and Helicobacter pylori antigen. EGD demonstrated a 3 cm oozing pedunculated polyp in the gastric cardia which was resected after ligation with an endoscopic loop. He had a normal colonoscopy. Histology showed findings consistent with a hyperplastic polyp. A 6-month interval EGD with EUS demonstrated a 5 x 6 cm mass in the cardia extending into the lesser curvature. A second opinion was obtained in consideration of endoscopic submucosal dissection, however on repeat endoscopic evaluation, the polyp had extended through the lesser curvature into the antrum and thus was aborted. The patient underwent total gastrectomy, the pathology from which revealed multiple juvenile polyps in the stomach, including that previously classified as hyperplastic. He now has complete resolution of his symptoms and anemia. Genetic analysis revealed him to be heterozygous for a VUS of the SMAD4 gene, denoted SMAD4 c.1138A >G p.R380G. We plan to pursue surveillance of his remaining gastrointestinal tract given his clinic diagnosis of JPS. Discussion: The clinical diagnosis of JPS is typically made using the Jass criteria, meeting one of the following criteria: more than 5 juvenile polyps (JP) in the colorectum, multiple JP across the entire GI tract, or any number of juvenile polyps and a family history of juvenile polyps. Additionally, one study showed that in patients with JPS and a SMAD4 pathologic mutation, gastric polyposis is more prevalent than in patients with BMPR1A mutations. Our case reveals a rare case of a gastric juvenile polyposis in a patient with a SMAD4 VUS. We aim to highlight this variant and stress the importance of ongoing evaluation and surveillance in patients with atypical presentations.

Introduction: Musculoskeletal injuries (MSI) reportedly vary among gastrointestinal (GI) endoscopists. This comprehensive systematic review and meta-analysis assessed the prevalence, characteristics, and impact of MSI in GI endoscopy. Methods: We performed a comprehensive search of PubMed, Embase, and Web of Science databases from inception through March 2023 for studies reporting the MSI prevalence among GI endoscopists. The primary outcome was the prevalence of MSI injuries. Secondary outcomes included characteristics and impact of MSI. The pooled rates were generated using a proportion meta-analysis with the random-effects model. Odds ratios (OR) were used for between-groups comparisons. Results: Our analysis incorporated 21 studies encompassing 5,407 endoscopists. The overall MSI prevalence was 62% (95% CI: 53.4-70.5) (Figure 1A). MSI prevalence in GI fellows was 47.9% (235/527) (95% CI: 32.1-63.8), and it was 75.9% (291/362) (95% CI: 57.6-94.3) in interventional endoscopists. MSI prevalence was higher in female endoscopists compared to their male counterparts (73% vs. 63.2%; OR 1.84, 95% CI 1.32-2.56, P=0.0003) (Figure 1B). MSI prevalence was numerically lower in academic centers compared to non-academic settings but without a statistically significant difference (48.5% vs. 59.5%; OR 0.76, 95% CI 0.51-1.14, P=0.18) (Figure 1C). Interestingly, only 23.5% of endoscopists reported ergonomic training. Pooled prevalence estimates for common MSI types included low back pain (37.7%), neck pain (37.2%), thumb pain (34.2%), hand pain (32.2%), and shoulder pain (30.1%). Incidences of carpal tunnel syndrome and De Quervain's tenosynovitis were reported at 9.9% and 10%, respectively. Those afflicted with MSI reported various treatments: pain medications (37.7%), physical therapy (25%), splinting (11%), steroid injections (8.5%), and surgery (5.6%). Finally, 13.2% of those with MSI required time off work. All prevalence estimates of common MSI types with common treatments used are summarized in Table 1. Conclusion: Given MSI’s high prevalence and significant health burden among GI endoscopists, ergonomic endoscopic instrument redesign is critical. Implementing standardized ergonomic curricula in endoscopy training institutions and suites is essential. Further research to inform such an evidence-based ergonomic curriculum is paramount to mitigate MSI risk, especially considering the imminent shortage of gastroenterologists and increasing procedure volume.Figure 1 Table 1. - Outcomes Total Studies Total Number of Endoscopists With MSI Number of Endoscopists With Outcome of Interest % (95% CI) Received ergonomic training 7 2,523 839 23.5% (14.1, 32.8) Most common MSI types Low back pain 18 3,234 1,318 37.7% (28.6, 46.8) Neck pain 18 3,234 1,441 37.2% (28.4, 46.1) Thumb pain 15 3,072 1,352 34.2% (23, 45.3) Hand pain 13 2,821 1,081 32.2% (19.7, 44.6) Shoulder pain 16 3,102 1,015 30.1% (20.3, 39.8) De Quervain's tenosynovitis 3 326 42 10% (2.2, 17.8) Carpal tunnel syndrome 9 2,384 352 9.9% (4.7, 15.1) Treatment of MSIs Pain medications 14 1,638 683 37.7% (26.6, 48.7) Physical therapy 10 1,415 440 25% (14.1, 36) Splinting 10 1,346 178 11% (6.2, 15.9) Steroid injection 8 1,214 154 8.5% (2.9, 14.2) Surgery 10 2,466 238 5.6% (2.4, 8.8) Required time off work 16 2.921 509 13.2% (7.9, 18.5) Abbreviations: CI: confidence interval, MSI: musculoskeletal injury.

,therewasnoconsensusonwhichdesigntheypreferredto achieve that end. Greater than 95% deemed ergonomics as “ very ” or “ extremely ” important. Conclusion: Giventheknownhighprevalence of ERIamongendoscopist,it isnotsurprisingthatthevastmajorityof surveyrespondentsdesiremodi fi cations in thecurrent colonoscope,particularlyas regards customizable and more easily manipulated control surfaces. Professional societies and industry should work together to design scopes more aligned with best ergonomic principles.

Pancreatic fluid collections are a common complication of both interstitial and necrotizing pancreatitis. Drainage is indicated if there is a concern for superinfection or symptoms secondary to size or location. The proximity of the pancreas to the stomach

Introduction: The differential diagnosis for pelvic masses is broad ranging from gynecologic pathology to lower GI tract cancers. Upper GI tract pathology is rarely a consideration. We present a case of a large gastric gastrointestinal stromal tumor (GIST) presenting as a pelvic mass requiring multi-disciplinary collaboration for diagnosis and management. Case Description/Methods: A 52-year-old woman presented to the emergency department for 2 months of worsening pelvic pain and abdominal distention. Pelvic ultrasound demonstrated a large (13.8 x 6.3 x16 cm), complex, cystic mass in the pelvis that appeared to arrive from the left ovary. Laboratory studies revealed an elevated CA* 125 (43.2 U/mL) and CEA 19-9 (47 U/mL). She was offered pelvic mass debulking. To assist with staging, computed topographic (CT) imaging and endoscopic ultrasound (EUS) were performed prior to her scheduled surgery. Abdominal CT showed a large, heterogeneously enhancing multi-septated pelvic mass originating from the gastric antrum. Multiple hypodense solid lesions noted in the liver concerning for metastatic disease. Esophagogastroduodenoscopy (EGD) revealed a 2 cm subepithelial lesion in the gastric antrum and EUS showed a 9.7 x 5 cm highly vascular, hypoechoic and heterogenous submucosal lesion with multi-cystic component arising from the muscularis propria. Fine needle biopsy demonstrated spindled cells with elongated nuclei positive for DOG1 and CD 117 (negative for desmin and S100) consistent with GIST. Targeted biopsy of the liver lesion was negative for malignant cells. Due to the lesion size and concern for hepatic metastases, imatinib 400mg daily was initiated. The gastric mass was reduced to 3.2 x 4.9 x7.1 cm after 3 months of therapy. At the time of this report, the patient continues chemotherapy to optimize her surgical candidacy. She is also planned for repeat targeted hepatic lesion biopsy (Figure 1). Discussion: GISTs are a rare (< 1% of GI tumors), distinct set of mesenchymal tumors, originating from the interstitial cells of Cajal. Most tumors are gastric (50%-75%) and are often asymptomatic. When present, symptoms include may include bleeding, obstruction, or mass effect as in our case. This case highlights the importance of complete imaging of pelvic masses prior to embarking on surgical therapy.Figure 1.: A. Coronal view of the 13.8 x 6.3 x16 cm gastric mass B. Saggital view of the 13.8 x 6.3 x16 cm gastric mass C. Endoscopic view of 2 cm antral sub-epithelial lesion D. EUS w/ FNB of the lesion.

Introduction: Amebiasis, caused by the protozoan Entamoeba histolytica, is the leading cause of infectious diarrhea worldwide. Areas with highest rates of infection include India, parts of Central and South America, Mexico, and Africa. Worldwide, amebiasis affects more than 50 million people with approximately 100,000 deaths annually. Though amebiasis is considered endemic worldwide, the prevalence of infections in the United States is relatively low, estimated to be about 1%-4%. Interestingly, despite its global impact, E. histolytica infections are largely asymptomatic, with only 10%-20% of those infected develop symptoms. Typically, intestinal amebiasis is diagnosed via stool microscopy, stool antigen detection, or stool polymerase chain reaction. Herein, we present a case of patient intestinal amebiasis diagnosed via routine screening colonoscopy. Case Description/Methods: The patient is a 56-year-old healthy man who was referred to the gastroenterology clinic for an index colonoscopy. He had no personal or family history of colorectal cancer. He denied any constitutional symptoms like fevers, chills, weight loss or malaise. He also denied any gastrointestinal symptoms including decreased appetite, nausea, vomiting, abdominal pain, diarrhea, constipation, and bloody bowel movements. Upon further questioning, the patient states that he often travels for work. Two months prior to his colonoscopy, he was in Japan for about a month. Within the past year, he has traveled to Australia and Norway, each visit staying for approximately a month. To his recollection, he usually drinks bottled water and eats cooked food, except for raw fish and sushi in Japan. His colonoscopy showed multifocal cecal ulcerations with surrounding exudate and friability (Figure 1). Biopsy samples taken from the cecum showed active colitis with organisms consistent with E. histolytica. He was treated with a 7-day course of paromomycin. Discussion: This case highlights the importance of maintaining a broad differential diagnosis for colonic ulcerations and obtaining a good social history, including travel history for all patients. The endoscopic and histopathologic appearance of the mucosal lesions and their biopsies in this case are hallmarks of the disease but clinicians in the US may not consider it due to low prevalence. It is important to correctly identify and treat amebiasis to prevent the risk of worsening disease and decrease the risk of spread to family members.Figure 1.: Amebiasis on colonoscopy: Multifocal cecal ulcerations.

Introduction: Chlamydia trachomatis (C. trachomatis) is a common sexually transmitted bacterial infection with rising incidence. Diagnosis can be challenging as the infection is often asymptomatic. Additionally, lack of awareness of the condition can contribute to missed diagnosis in patients with proctitis symptoms. We present a case series of 2 patients with rectal chlamydia highlighting their distinct clinical presentations and diagnostic challenges. Case Description/Methods: Case 1: A 33 year-old man with human immunodeficiency virus (HIV) on antiviral therapy presented with rectal pain and bleeding for 2 months with multiple emergency room visits and a surgical evaluation. Unable to tolerate an anoscopy due to pain, he received therapy for a possible anal fissure. Labs showed a normocytic anemia and an undetectable HIV viral load. Computed tomography (CT) of the abdomen showed rectal and distal sigmoid thickening. Colonoscopy showed a 5 cm rectal ulcer and ulcerations in the anal canal and biopsies demonstrated active inflammation. A rectal swab was positive for C. trachomatis. The patient was prescribed a 21 day course of doxycycline and his rectal pain and bleeding quickly improved. Case 2: 55 year old man with history of gastric adenocarcinoma had anterior rectal wall thickening noted on routine CT surveillance. He was asymptomatic. Flexible sigmoidoscopy showed erythema in the rectal wall with a single small ulcer. Biopsy showed reactive inflammatory changes. Following the procedure he noted episodes of hematochezia and endorsed receptive anal intercourse prompting testing with rectal swab which confirmed C. trachomatis. He was treated with doxycycline. Discussion: Individuals at risk of rectal C. trachomatis are often not screened in extragenital sites, possibly due to lack of awareness, which leads to higher disease incidence. Patients’ presentations can vary, and symptoms can mimic other processes like NSAID use, solidary ulcer syndrome, or malignancy. Doxycyline is the preferred treatment due to azithromycin having treatment failure rates as high as 22% due to low rectal penetration and antimicrobial resistance. Giving the rising prevalence, it is imperative that the diagnosis of rectal chlamydia be considered in sexually active patients or patients with proctitis symptoms. Routine screening should be considered to help identify asymptomatic infections early and to combat the spread of this disease.

Introduction: Acute esophageal necrosis (AEN), commonly referred to as black esophagus due to the striking circumferential blackening of the esophageal mucosa, is a rare clinical condition with a prevalence of up to 0.2%. The etiology of this condition is unclear but thought to involve the interplay of ischemia and gastric outlet obstruction with gastroesophageal reflux. As this condition carries with it a mortality rate of nearly 40%, prompt recognition and aggressive management is of the utmost importance to prevent perforation or stricture. Considering this, AEN should be recognized as a possible outcome of an ischemic event and considered a potential cause of spontaneous esophageal perforation. Case Description/Methods: A 43-year-old female with a history of epithelioid hemangioendothelioma status post resection, Crohn’s colitis in remission, and recent hospitalization for a complicated urinary tract infection and abdominopelvic ascites concerning for malignancy with hospitalization complicated by cardiopulmonary arrest presented to the emergency department 8 days after discharge following a near syncopal episode. She was found to be hypotensive with tachycardia concerning for shock. She was started on broad spectrum antibiotics, 3 vasopressors, intubated, and admitted to the ICU. A CT scan of her chest, abdomen, and pelvis showed extensive pneumomediastinum concerning for esophageal perforation and pneumatosis intestinalis. Perforation was confirmed utilizing serial chest x-rays with contrast demonstrating a right-sided esophageal leak at the gastroesophageal junction. Both cardiothoracic surgery and gastroenterology were consulted, she was not deemed a surgical candidate and endoscopy with covered stent placement was planned. Endoscopy revealed a black esophagus consistent with an ischemic process throughout the entire esophagus and pneumatosis intestinalis suggesting small bowel ischemia. Stenting was aborted and the findings were discussed with the patient’s family who decided to pursue comfort measures. The patient died the following day (Figure). Discussion: It has been demonstrated that critically ill patients often experience low flow states, poor nutritional status, and disruption of intrinsic repair mechanisms. Coupled together, these insults increase the risk of developing AEN and must be acknowledged as a possible complication in this patient population. Although this is a rare condition, it should be recognized as a potential outcome of an ischemic event.Figure 1.: Images A-D depicts a diffusely abnormal mucosa throughout the esophagus, characterized by black/brown tissue consistent with ischemia.

Introduction: Alpha-gal syndrome (AGS) is a rare, acquired allergic reaction to mammalian meat that most commonly develops in the United States following tick exposure. The arthropod bite leads to formation of a specific IgE antibody to oligosaccharide galactose-α-1,3-galactose (alpha-gal). Patients with AGS classically present with a myriad of symptoms that can range in severity from localized pruritis to anaphylaxis. There are however a subset of patients with AGS that only present with gastrointestinal symptoms, which can present a unique diagnostic challenge. Herein, we describe a classic case of AGS in a patient with markedly elevated alpha-gal IgE levels at diagnosis that normalized following strict dietary modification. Case Description/Methods: A 78-year-old man initially presented to the GI clinic for evaluation of a 6-month history of episodic vomiting and diarrhea occurring almost exclusively late in the evening. Symptoms would typically manifest as abrupt onset of vomiting with watery diarrhea and overwhelming malaise. Notably, he denied any history of chronic GI complaints prior to this onset. No trigger foods were initially identified and his hematologic, blood chemistry, and infectious lab evaluations were unrevealing. He then started to experience a concomitant urticarial eruption, which, in conjunction with new historical data regarding a particular tick bite exposure several months prior to symptom onset, prompted evaluation for AGS. Serologic assessment revealed significantly elevated alpha-gal IgE, which comprised a significant quantity of total serum IgE. The patient ultimately received a diagnosis of AGS and, following avoidance of beef, dairy, and gelatin-containing products, experienced normalization of both symptoms and alpha-gal IgE within one month. Discussion: The mechanism behind the pathogenesis of AGS remains poorly understood. The clinical presentation, on the other hand, has become a more widely recognized syndrome. This patient displayed the classic gastrointestinal, dermatologic, and likely cardiovascular symptoms that are seen in AGS. This syndrome is distinct from other food allergy syndromes in that the driving allergen is a carbohydrate, of which the absorption is delayed to several hours following food exposure. This classic 3-6 hour delay from time of food exposure to onset of symptoms is the hallmark feature that makes AGS distinct from other anti-protein epitope IgE mediated allergic reactions and makes diagnosis so elusive.

Introduction: Primary gastrointestinal lymphomas represent 1-4% of GI malignancies. Mantle cell lymphoma (MCL) is a Non-Hodgkin’s lymphoma that -in the GI tract- is rare, representing fewer than 5% of primary gastrointestinal lymphomas. The clinical course ranges from indolent to aggressive. A patient’s symptoms, imaging, and endoscopic findings can be non-specific, making the diagnosis of MCL challenging. We present a patient with an elusive intestinal lesion that was diagnosed as a primary gastrointestinal MCL. Case Description/Methods: A 74-year-old man with a history of hypothyroidism and prostate cancer treated with prostatectomy presented with polyarthralgia, fatigue, dyspepsia and anorexia with 20-pound weight loss over 2 months. His physical exam revealed no abnormal findings. Laboratory studies revealed peripheral eosinophilia on complete blood count with an absolute eosinophil count of 1800 cells/mcL. Computed tomography showed a soft tissue lesion in the region of the cecum and ascending colon with multiple right lower quadrant sub-centimeter mesenteric lymph nodes. He underwent subsequent colonoscopy that demonstrated a normal appearing cecum and ascending colon. He was then evaluated with PET, which showed hypermetabolic activity at the ileocecal valve. He underwent a diagnostic laparoscopy which found no evidence of an extraluminal colonic mass nor mass in the mesentery or omentum. Repeat colonoscopy revealed a lesion in the terminal ileum with biopsies noting atypical lymphoid infiltrate with t(11;14)(q13;q32) on FISH analysis and the patient was diagnosed with MCL. Patient’s symptoms resolved and given the asymptomatic and localized nature with isolated gastrointestinal extra-nodal disease he is monitored with serial imaging. Discussion: Primary gastrointestinal MCL is a rare disease with a variety of clinical presentations. The diagnosis can be challenging as patients who are symptomatic present with vague reports of anorexia, bloating or abdominal pain. Radiographically the lymphoma may or may not be apparent. Endoscopically the MCL can range from normal appearing mucosa to polypoid or ulcerated lesions. In this patient, it is likely that the ileal lesion periodically prolapsed into the colon- explaining the imaging findings. In the initial colonoscopy, the prolapsed segment spontaneously reduced, leaving only the falsely reassuring normal colon. High clinical suspicion based on subsequent imaging led to repeat colonoscopy with ileal intubation and tissue sampling, yielding the diagnosis.

BACKGROUND Nearly one-third of colorectal cancers (CRC) arise via the serrated pathway. CT colonography (CTC) is a CRC screening examination. Endoscopic detection of sessile serrated polyps (SSPs) varies widely; it is unknown whether CTC effectively detects SSPs. The aim of this study is to determine whether CTC detects SSPs at an institution that performs a large volume of CTC. METHODS We conducted a search of pathology records to identify serrated polyps (SPs) from 2005 to 2012. We extracted demographic data from the electronic health records (EHRs) of subjects with an SSP and examined endoscopy reports for location and size of each SSP. We identified subjects with a CTC within 1 year prior to the colonoscopy that found an SSP, and determined if the CTC identified the SSP. RESULTS Our search found 3978 subjects with SP over the 7-year period. Seven hundred thirty-two subjects had at least 1 SSP. Eightytwo subjects had CTC done within 1 year prior to the colonoscopy that identified SSP. Seventy-nine subjects' polyps were identified on CTC. CT colonography was done an average of 38 ± 54 days prior to colonoscopy. One hundred fifteen SSPs were identified endoscopically. A total of 48.7% of all SSPs were identified via CTC; larger SSPs were more likely to be seen on CTC (P < .001), and 69.6% of SSPs larger than 10 mm were found via CTC. Proximal SSPs were more often identified than distal SSPs (P = .005). CONCLUSION Given the miss rate for SSPs on CTC, endoscopists should be vigilant about examining the proximal colon in subjects referred after CTC, even if the imaging does not reveal a proximal polyp.

Introduction: An ileal conduit is a common urinary diversion procedure for patients after cystectomy. Problems with the conduit can arise including ureteroileal anastomotic strictures and conduit stenosis1,2. Ileal conduit strictures are uncommon, occurring in no more than 15% of cases and typically years after conduit creation3. We present a novel case of endoscopic stenting as treatment for an ileal conduit stricture. Case Description/Methods: A 50-year-old man, with ileocolonic Crohn’s disease status post ileal pouch anal anastomosis ten years prior, and abdominal mucinous adenocarcinoma status post pelvic exenteration with ileal conduit creation one year prior, was referred to gastroenterology for hematuria from his conduit. CT imaging revealed fat stranding surrounding the ileal conduit concerning for recurrent inflammatory disease. Enteroscopy of the ileal conduit showed erythema, tissue friability, and a stricture most likely due to ischemia (Figure 1A, 1B). Over the next month, he developed bilateral ureteral obstruction and hydronephrosis from progression of his ileal conduit stricture. To relieve the obstruction, a 10mm x 60mm fully covered biliary stent was placed and sutured externally to the skin. The stent remained for 48 hours before dislodging. Two weeks later, a fully covered 10mm x 60mm self-expanding metal biliary stent was placed and sutured externally in a more robust manner (Figure 1C). The stent remained in place for two months before dislodging. Enteroscopy one week later showed dilation of the conduit stricture (Figure 1D). A loopogram by Urology showed improved patency and stricture resolution. He was prescribed daily conduit catheterization to prevent stricture recurrence and has not had additional hematuria or hydronephrosis. Discussion: Ileal conduits are a common method of urinary diversion in patients with pelvic malignancy. Ischemic strictures, while rare, are the most common intra-conduit complication3. Current management options involve surgery or endoscopic balloon dilatation. Retrograde stenting has not been well explored. Stenting has been described in managing stomal stenosis and ureteroileal anastomosis strictures4,5. Our patient presents a rare situation of an ileal conduit stricture present in the absence of other complications and treated with retrograde stenting. This is a viable option for patients who are poor surgical candidates or as a bridge to definitive treatments.Figure 1.: A - Endoscopic visualization of ileal conduit stricture, B - Initial loopogram with areas of stenosis, C - Stent placement, D - Repeat loopogram with improved luminal patency.