Novel Endoscopic Findings of Lesions with a Short White Hair-like Appearance in the Lower Esophagus.

Objective The presence of a short white hair-like appearance in the lower esophagus has recently been noted during esophagogastroduodenoscopy (EGD) at our institution. Histological findings showed that this formation was a spiked protrusion of the esophageal papilla. The results regarding the prevalence of such lesions in individuals who underwent EGD examinations as part of medical checkup procedures are herein presented. Methods The EGD results of 14,338 individuals (9,225 males, 5,113 females; mean age 54.0±9.8 years) were examined. The findings related to the presence of multiple lesions with a short white hair-like appearance in the lower esophagus of patients with reflux esophagitis, esophageal squamous papilloma, or gastric mucosal atrophy (GMA), as well as the hiatal hernia width, were investigated. Results Endoscopic findings indicating short white hair-like appendages in the lower esophagus were noted in 167 patients, with a prevalence rate of 1.2%. A female sex, younger age, lower body mass index, lower percentages of habitual smoking and drinking, and the presence of esophageal squamous papilloma were characteristic features of cases with such findings. In addition, a significantly lower prevalence of reflux esophagitis and a smaller diaphragmatic hiatus size were observed. A multiple logistic regression analysis indicated that a female sex, absence of reflux esophagitis, presence of esophageal squamous papilloma, and a smaller diaphragmatic hiatus were factors significantly related to the presence of these short white hair-like appendages. An analysis of circumferential localization revealed the main location to be the left-posterior wall. Conclusion This study is the first to report the prevalence of multiple short white hair-like appendages in the lower esophagus. The occurrence of such lesions is inversely associated with the presence of reflux esophagitis.

Prevalence of Gastric Epithelial Tumors in Helicobacter pylori-uninfected Individuals Undergoing a Medical Checkup.

Objective This study investigated the prevalence of gastric epithelial tumor in Helicobacter pylori-uninfected subjects who underwent esophagogastroduodenoscopy (EGD) as part of an annual checkup. Methods A total of 20,540 EGD examinations of H. pylori-uninfected individuals (12,917 men, 7,623 women; mean age 51.5±9.2 years old) were performed between April 2016 and March 2023. The prevalence of gastric epithelial tumor discovery and the size and location of each lesion type were analyzed. Results According to 20,540 examinations, 61 gastric epithelial tumors were endoscopically and histologically diagnosed in 58 of the subjects, with a prevalence rate of 0.28%. These tumors included signet-ring carcinoma (n=10, 0.05%), gastric adenocarcinoma of fundic-gland type (n=10, 0.05%), intestinal-type well-differentiated adenocarcinoma (n=2, 0.01%), and raspberry-type gastric foveolar tumors (n=36, 0.18%). One subject had two intestinal-type well-differentiated adenocarcinomas, and two each had two raspberry-type gastric foveolar tumors. The mean sizes of the signet-ring carcinomas, gastric adenocarcinoma of fundic-gland type, intestinal-type well-differentiated adenocarcinomas, and raspberry-type gastric foveolar tumors were 6.4, 4.7, 5.0, and 3.4 mm, respectively. Each lesion was located at a specific site in the stomach characteristic of its type. Conclusion In the present H. pylori-uninfected subjects, the prevalence of gastric epithelial tumors found on an EGD examination was 0.28%. Endoscopic examination should be performed in H. pylori-uninfected individuals to detect such tumors in characteristic locations.

Gastric Flat Elevated Undifferentiated Signet-ring Cell Mucosal Cancer Lesion Detected in a Case without Helicobacter pylori Infection.

Protruded signet-ring cell carcinoma (SRCC) is extremely rare. We herein report a rare case of flat elevated gastric SRCC in a patient without Helicobacter pylori infection. Esophagogastroduodenoscopy of a woman in her 50s revealed a flat, whitish lesion in the gastric body with elevation. Histological results of an endoscopically biopsied specimen led to a diagnosis of SRCC. Resection using endoscopic submucosal dissection was performed, and histology results revealed that the tumor was localized in the lamina propria. The size was 10×6 mm, and a protrusion had been formed by SRCC enlargement without destruction of the surface epithelium structure.

Prevalence of Raspberry-type Gastric Foveolar-type Tumor in Individuals Undergoing Medical Checkups.

Objective This study was performed to clarify the prevalence of raspberry-type gastric foveolar-type tumors, along with the time-course changes in the size and clinical course. Methods The subjects were 10,663 consecutive patients who underwent a medical checkup between April 2016 and March 2022, including an esophagogastroduodenoscopy (EGD) examination and determination of Helicobacter pylori infection status (uninfected, positive, post-eradication). The presence of characteristic reddish polypoid lesions in the stomach was investigated, and a diagnosis of raspberry-type gastric foveolar-type tumor was made based on histological findings. Results Thirty-eight cases had gastric polyps with a raspberry-like appearance on endoscopy, with 29 lesions in 28 cases endoscopically and histologically diagnosed as a raspberry-type gastric foveolar-type tumor. All of the affected subjects were determined to be H. pylori-uninfected. The prevalence of this type of lesion in all subjects was 0.26%, while that in the 6,635 H. pylori-uninfected subjects was 0.42%. An older age and the presence of a fundic gland polyp were found to be significant risk factors associated with the occurrence of the tumor. The mean size was 3.8±1.9 (range: 2-10) mm, and the location was in a fundic gland area in all affected subjects. Furthermore, examinations of previous EGD images revealed that two-thirds of the lesions had not changed in size, while follow-up EGD findings showed that lesions ≤5 mm in size had disappeared after a biopsy procedure. Conclusion The prevalence of raspberry-type gastric foveolar-type tumors was 0.42% in H. pylori-uninfected subjects. More than half of the lesions were too small to be removed by an endoscopic biopsy.

Long-lasting renal dysfunction following tacrolimus induction therapy in ulcerative colitis patients.

Although tacrolimus (TAC) has remarkable effects in ulcerative colitis (UC) patients when given as remission induction therapy, some can develop renal dysfunction during TAC administration, resulting in withdrawal, though related details remain poorly understood. This study was conducted to determine the impact of oral TAC on renal function for remission induction therapy in UC patients. Fifty-five patients (10 elderly, 45 non-elderly) with UC and treated with oral TAC at our hospital were retrospectively evaluated. Renal function was assessed using estimated glomerular filtration rate (eGFR). Although a high clinical response to TAC was seen in both elderly and non-elderly, a decline in eGFR was noted in nearly all patients regardless of age, with a maximum change of -34.4% from the baseline value at week 11. Furthermore, eGFR decline recovered quickly after TAC discontinuation, though did not return to the baseline at two years following cessation. The rate of eGFR change at week 12 was significantly associated with patient age (ß = -0.3242, p = 0.0103) and peak serum trough level during TAC treatment (ß = 0.3563, p = 0.0051). Furthermore, the rate of decline in eGFR was significantly greater during treatment with TAC in the elderly as compared to non-elderly, with a large difference in eGFR decline rate between those groups also noted at two years after withdrawal of treatment. Careful attention to renal function when administering oral TAC for UC is important and changes in eGFR should be monitored closely in elderly patients even after treatment cessation.

Application of Convolutional Neural Networks for Diagnosis of Eosinophilic Esophagitis Based on Endoscopic Imaging.

Subjective symptoms associated with eosinophilic esophagitis (EoE), such as dysphagia, are not specific, thus the endoscopic identification of suggestive EoE findings is quite important for facilitating endoscopic biopsy sampling. However, poor inter-observer agreement among endoscopists regarding diagnosis has become a complicated issue, especially with inexperienced practitioners. Therefore, we constructed a computer-assisted diagnosis (CAD) system using a convolutional neural network (CNN) and evaluated its performance as a diagnostic utility. A CNN-based CAD system was developed based on ResNet50 architecture. The CNN was trained using a total of 1192 characteristic endoscopic images of 108 patients histologically proven to be in an active phase of EoE (≥15 eosinophils per high power field) as well as 1192 normal esophagus images. To evaluate diagnostic accuracy, an independent test set of 756 endoscopic images from 35 patients with EoE and 96 subjects with a normal esophagus was examined with the constructed CNN. The CNN correctly diagnosed EoE in 94.7% using a diagnosis per image analysis, with an overall sensitivity of 90.8% and specificity of 96.6%. For each case, the CNN correctly diagnosed 37 of 39 EoE cases with overall sensitivity and specificity of 94.9% and 99.0%, respectively. These findings indicate the usefulness of CNN for diagnosing EoE, especially for aiding inexperienced endoscopists during medical check-up screening.

Endoscopic diagnosis and screening of Barrett's esophagus: Inconsistency of diagnostic criteria between Japan and Western countries.

Barrett's esophagus (BE) is an endoscopically identifiable premalignant condition for esophageal adenocarcinoma (EAC). To diagnose BE precisely, careful inspection of the anatomic landmarks, including the esophagogastric junction and the squamocolumnar junction is important. The distal end of the palisade vessels and the proximal end of the gastric folds are used as the landmark of the esophagogastric junction in endoscopic diagnosis, with the latter solely used internationally, except in some Asian countries, including Japan. In addition, the diagnostic criteria adopted internationally for BE are inconsistent, particularly between Japan and Western countries. Recently updated guidelines in Western countries have included length criteria, with a 1-cm threshold of columnar epithelium by endoscopic observation and/or histologic confirmation of the presence of specialized intestinal metaplasia. Since BE is endoscopically diagnosed at any length without histologic assessment in Japan, the reported prevalence of short-segment BE is very high in Japan compared with that in Western countries. Although guidelines on screening exist for BE, the current strategies based on the presence of chronic gastroesophageal reflux disease with multiple risk factors may miss the opportunity for early detection of EAC. Indeed, up to 40% of patients with EAC have no history of chronic gastroesophageal reflux disease. To discuss BE on the same footing worldwide, standardization of diagnostic criteria, screening indication, and establishment of effective techniques for detecting dysplastic lesions are eagerly awaited. Japanese guidelines for BE should be revised regarding the length criteria, including the minimum length and long-segment BE, in line with the recently updated Western guidelines.

Heterotopic Gastric Mucosa in Middle Esophagus Complicated with Esophageal Ulcers.

Heterotopic gastric mucosa (HGM) of esophagus, primarily occurring in cervical esophagus, is usually asymptomatic. A healthy woman (mid-40s) with postprandial heartburn was diagnosed with middle esophageal HGM and esophageal ulcers by esophagogastroduodenoscopy. Using 8-channel pH monitoring, a sensor near the HGM area detected postprandial acid phase (pH 3-4), while areas adjacent to the proximal and distal sensors were neutral, suggesting acid secretion from the HGM. A biopsy showed fundic gland tissue expressing H+/K+-ATPase and pepsinogen-I. Oral vonoprazan improved the clinical symptoms and endoscopic findings. This is the first report using 8-channel pH monitoring to diagnose extremely rare middle esophageal HGM.

The Simultaneous Onset of Pancreatitis and Colitis as Immune-related Adverse Events in a Patient Receiving Nivolumab Treatment for Renal Cell Carcinoma.

Immune checkpoint inhibitors (ICIs), which have anti-tumor effects, are currently approved for treatment of several kinds of advanced malignancies. However, with their increasing use, a variety of immune-related adverse events (irAEs) in administered patients have been reported. We herein report a rare case of the simultaneous onset of acute pancreatitis and colitis as irAEs during nivolumab treatment given to a patient with renal cell carcinoma, who then shown marked improvement with corticosteroid therapy.

Evaluations of Gastric Acid Pocket Using Novel Vertical 8-Channel pH Monitoring System and Effects of Acid Secretion Inhibitors.

BACKGROUND/AIMS: The gastric acid pocket has an important role in gastroesophageal reflux disease development. In this study, we utilized a novel 8-channel pH monitoring system with sensor intervals of 1 cm on the vertical axis for evaluation of postprandial gastric acid pocket in healthy Japanese adults, as well as the effects of vonoprazan and rabeprazole. METHODS: Twelve healthy volunteers without Helicobacter pylori infection were enrolled. A catheter was inserted transnasally and positioned under X-ray guidance, then postprandial acid pocket formation was monitored over time in a sitting position. Thereafter, acid pocket changes were assessed following administration of vonoprazan (20 mg) or rabeprazole (20 mg). RESULTS: The gastric acid pocket was successfully measured by use of the present system in 10 cases, while failure occurred in 2 because of inappropriate catheter positioning. Observed acid pockets were visualized with a mean length of 2.2 ± 0.4 channels on the top layer of food contents approximately 20 minutes after finishing a meal. There were some variations for lasting time of the acid pocket. Complete elimination within 3 hours after administration of vonoprazan was noted in all cases. Likewise, following administration of rabeprazole, the acid pocket was eliminated in 7 cases, while acidity was reduced though the pocket remained observable in 3. CONCLUSION: s Gastric acid pocket observations were possible using our novel vertical 8-channel sensor catheter. The present findings showed that vonoprazan strongly suppressed acid secretion within a short period, suggesting its effectiveness for gastroesophageal reflux disease treatment.

Factors for Negative Result in Serum Anti-Helicobacter pylori IgG Antibody Test in Adult Subjects With Nodular Gastritis: A Single-center Study.

AIM: Nodular gastritis has been demonstrated to be strongly associated with Helicobacter pylori infection. The present retrospective study was performed to elucidate factors related to a negative serum antibody test result in adults with nodular gastritis. MATERIALS AND METHODS: We investigated 116 H. pylori-positive subjects endoscopically diagnosed with nodular gastritis and subjected to a serum anti-H. pylori immunoglobulin G (IgG) antibody test. The degree of gastric mucosal atrophy and the presence of spotty redness in the gastric body and fornix were carefully determined by observations of endoscopic images. RESULTS: Of the 116 investigated subjects, 108 were positive and 8 negative in serum anti-H. pylori IgG antibody test results. The degree of gastric mucosal atrophy was mild in seven among eight seronegative cases. The levels of pepsinogen II in serum in patients with negative antibody test findings were significantly lower as compared to those found positive, while the pepsinogen I/II ratio tended to be higher in subjects shown negative by the test. Only 1 of 69 with spotty redness was negative in serum anti-H. pylori IgG antibody testing, while 7 of 47 without spotty redness were negative. Multiple logistic regression analysis of subjects with a negative test result revealed that the absence of spotty redness shown by endoscopy was a significant risk factor. CONCLUSION: The absence of spotty redness, which may reflect the degree of gastric body inflammation, is a significant factor indicating increased risk for a negative serum anti-H. pylori IgG antibody test result in subjects with nodular gastritis.

Primary Extragastrointestinal Stromal Tumor of Greater Omentum with Intraperitoneal Bleeding.

Gastrointestinal stromal tumors (GISTs) develop in the digestive tract, mainly in the stomach, small intestine, colon, or esophagus. However, primary tumors with the same pathologic features as GISTs have been reported to occur outside of the digestive tract and are called extragastrointestinal stromal tumor (EGIST). We herein report a rare case of EGIST arising from the greater omentum in a patient with abdominal pain caused by intraperitoneal bleeding from the tumor.

Similarity and difference in the characteristics of eosinophilic esophagitis between Western countries and Japan.

Over the past two decades, the incidence and prevalence of eosinophilic esophagitis (EoE) have risen rapidly, especially in Western countries, with cases in Japan also showing a gradual increase in recent years. However, similarities and differences regarding the characteristics of EoE between Western countries and Japan remain to be clearly elucidated. The current clinical guidelines for diagnosis include symptoms related to esophageal dysfunction and dense eosinophilic infiltration in the esophageal epithelium. Most affected patients in Japan are diagnosed incidentally during a medical health check-up and asymptomatic cases with typical endoscopic findings suggestive of EoE are frequently encountered. Clinical characteristics of EoE in Japanese are similar to those seen in Western populations. The predominant symptom is dysphagia, with food impaction extremely rare in Japanese cases. Linear furrows are the most frequently reported characteristic endoscopic finding, while an esophageal stricture or narrow caliber is rarely observed. Treatment strategies for EoE include drugs, dietary restrictions, and endoscopic dilation when the disease is advanced with stricture formation. Although single therapy using a proton-pump inhibitor has been shown to achieve symptomatic and histological response in the majority of patients in Japan, no prospective randomized control studies that evaluated drug or elimination diet therapy have been presented. Overall, EoE has similar clinical characteristics between Japanese and Western populations, while disease severity seems to be milder in Japan. Additional studies are necessary to determine genetic factors, natural history of the disease, and treatment efficacy of drugs and elimination diet as compared to Western populations.

Clinical Characteristics and Treatment Outcomes of Patients with Eosinophilic Esophagitis and Eosinophilic Gastroenteritis.

BACKGROUND: Eosinophilic esophagitis (EoE) and eosinophilic gastroenteritis (EGE), part of the spectrum of eosinophilic gastrointestinal disorders (EGID), share pathogenic similarities. We examined differences regarding clinical characteristics and treatment outcomes between EoE and EGE cases. METHODS: Two-hundred fifteen EGID patients, including 181 with EoE and 34 with EGE, diagnosed at Shimane University Hospital between February 2011 and March 2019 were enrolled. Information regarding clinical parameters and treatment outcomes was reviewed. RESULTS: EoE showed significant male predominance (82.3%) as compared with EGE (50.0%) (p < 0.001). Furthermore, patients with EoE were significantly older and had a higher body mass index (24.8 ± 4.0 vs. 22.2 ± 4.3, p < 0.05). Over 90% of the EoE patients were initially given proton pump inhibitor (PPI) treatment, of whom 73.2% showed clinical and histological remission. Vonoprazan, a more potent acid inhibitor than PPI, was effective in two-thirds of the nonresponsive EoE patients initially treated with a PPI. In contrast, oral glucocorticoid administration was mainly given to patients with EGE (58.8%). Of 13 EGE patients treated with a food-elimination diet, responsible foods were successfully identified in 9, with 7 controlled in a state of remission without glucocorticoid therapy. CONCLUSIONS: We found different clinical characteristics and treatment strategies in the present EoE and EGE cases. Most of the EoE patients responded to and were maintained by acid suppressive therapy, using PPI or vonoprazan. For EGE patients, glucocorticoid administration was mainly used though food-elimination diet therapy also showed beneficial effects.

Prevalence of functional dyspepsia-like symptoms in ulcerative colitis patients in clinical remission and overlap with irritable bowel syndrome-like symptoms.

Objective: Quiescent ulcerative colitis (UC) patients often have irritable bowel syndrome (IBS)-like symptoms and we recently showed that the prevalence of IBS-like symptoms in UC patients in clinical remission was significantly higher as compared to healthy control subjects. However, the prevalence of functional dyspepsia (FD)-like symptoms in quiescent UC patients remains unknown. The purpose of this study was to evaluate the prevalence of FD-like symptoms and the overlap with IBS-like symptoms in such patients.Materials and Methods: We reanalyzed the records of UC patients in remission using the subject cohort from our previous study. Clinical remission was defined as a clinical activity index (CAI) value ≤4 for at least 6 months. Diagnoses of FD- and IBS-like symptoms were evaluated by questionnaire according to the Rome III criteria.Results: One hundred seventy-two UC patients in clinical remission and 330 healthy control subjects were analyzed. Of the 172 patients, 9 (5.2%) met the criteria of FD, which was comparable with the controls (22/330, 6.7%). The prevalence rate of FD-like symptoms in UC patients with IBS-like symptoms (7/46, 15.2%) was lower as compared to that of the control subjects (6/16, 37.5%). On the other hand, a high percentage of the UC patients with FD-like symptoms also had IBS-like symptoms (7/9, 77.8%).Conclusions: Although the prevalence of FD-like symptoms in quiescent UC patients with IBS-like symptoms was low, UC patients with FD-like symptoms frequently had IBS-like symptoms.

Eosinophilic Granulomatosis with Polyangiitis Initially Diagnosed as Eosinophilic Gastroenteritis.

We herein report two cases of eosinophilic granulomatosis with polyangiitis (EGPA) initially diagnosed as eosinophilic gastroenteritis (EGE) based solely on endoscopic biopsy results. One year after the EGE diagnosis, one patient presented with multiple purpura, and skin biopsy findings resulted in a change of the diagnosis to EGPA. In another patient, multiple skin and colonic ulcerations emerged eight years after the diagnosis of EGE, at which time histological examinations of endoscopic biopsy specimens revealed vasculitis, and the diagnosis was changed to EGPA. Physicians should be aware of the possible existence of EGPA in cases diagnosed as EGE.

Is Asymptomatic Esophageal Eosinophilia the Same Disease Entity as Eosinophilic Esophagitis?

Eosinophilic esophagitis (EoE) is an allergic inflammatory disorder that is characterized clinically by symptoms related to esophageal dysfunction and histologically by eosinophil-predominant inflammation.1,2 Its prevalence has been increasing rapidly in both Western and Asian countries. In Japan, most of the cases of esophageal eosinophilia (EE) are found in an upper endoscopy examination for gastric cancer screening performed during a comprehensive health check-up.3,4 Indeed, we frequently encounter patients with asymptomatic EE showing typical endoscopic findings, such as linear furrows, as well as histologic findings compatible with EoE. However, the current clinical guidelines for EoE diagnosis include symptoms related to esophageal dysfunction, thus patients without symptoms do not fulfill the diagnostic criteria.1,2 The clinical characteristics remain to be fully elucidated,5 thus we aimed to clarify clinical features of asymptomatic EE as compared with those of EoE.

Circumferential distribution and clinical characteristics of esophageal cancer in lower esophagus: differences related to histological subtype.

BACKGROUND: Esophageal adenocarcinoma (EAC) is frequently found on the right-anterior wall of the distal esophagus in short-segment Barrett's esophagus (SSBE) patients. However, the endoscopic characteristics of EAC in cases with long-segment BE (LSBE) and squamous cell carcinoma (ESCC) in the lower esophagus remain to be fully evaluated. Here, we determined the circumferential distribution and clinical characteristics of esophageal cancer occurring in the lower esophagus based on histological subtype. METHODS: We retrospectively reviewed the medical records of 150 patients with esophageal cancer (ESCC, n = 100; EAC, n = 50) diagnosed at our hospital or a related facility between January 2002 and June 2017, including information regarding endoscopic findings, etiology, and clinical parameters. RESULTS: Of the 100 patients with ESCC, 28 lesions were located in the lower esophagus, though characteristic circumferential distribution was not seen regardless of location. Those showed a greater frequency of smoking and drinking habit and gastric mucosal atrophy as compared to patients with EAC. Consistent with the previous reports, EAC in SSBE (n = 41) was frequently located on the right-anterior wall. Likewise, EAC at the esophagogastric junction (EGJ) in LSBE was frequently located on the right-anterior wall, while EAC distant from the EGJ showed no characteristic circumferential distribution. CONCLUSION: Our results showed no circumferential predilection for ESCC in the lower esophagus, suggesting that development of this type of lesion may be less affected by gastroesophageal reflux. In addition, EAC at the EGJ was frequently found on the right-anterior wall irrespective of BE length.

Vertical and Circumferential Localization of Esophageal Mucosal Breaks in Patients with Mild Reflux Esophagitis.

Objective Esophageal mucosal breaks are considered to occur circumferentially in locations with high exposure to acid. In the present study, we investigated the circumferential localization of esophageal mucosal breaks based on their distance from the esophagogastric junction. Methods The vertical and circumferential localization of 625 esophageal longitudinal mucosal breaks was examined in 398 patients with mild reflux esophagitis. Results The number of mucosal breaks in which the distal end was located 0-1 cm from the esophagogastric junction was 454, while those in which the distal end was located 1-2, 2-3, and >3 cm from the junction were 125, 28, and 18, respectively. There was a marked difference in the circumferential distribution among the groups defined by distance from that junction. Esophageal mucosal breaks whose distal end were located 0-1 cm from the esophagogastric junction were mainly found on the right anterior wall of the esophagus, while those located 1-2 cm from the junction were mainly found on the right wall, and those located 2-3 and >3 cm from the junction were mainly found on the posterior wall. Conclusion Esophageal mucosal breaks occurring relatively near the esophagogastric junction mainly exist on the right anterior wall, whereas those farther from that junction tend to exist on the posterior wall of the esophagus. The circumferential location of esophageal mucosa highly exposed to refluxed gastric contents changes based on the distance from the esophagogastric junction.

Distinction between Chronic Enteropathy Associated with the SLCO2A1 Gene and Crohn's Disease.

Background/Aims: We recently identified recessive mutations in the solute carrier organic anion transporter family member 2A1 gene (SLCO2A1) as causative variants of chronic nonspecific multiple ulcers of the small intestine (chronic enteropathy associated with SLCO2A1, CEAS). The aim of this study was to investigate the gastroduodenal expression of the SLCO2A1 protein in patients with CEAS and Crohn's disease (CD). Methods: Immunohistochemical staining for SLCO2A1 was performed with a polyclonal antibody, HPA013742, on gastroduodenal tissues obtained by endoscopic biopsy from four patients with CEAS and 29 patients with CD. Results: The expression of SLCO2A1 was observed in one of four patients (25%) with CEAS and in all 29 patients (100%) with CD (p<0.001). The three patients with CEAS without SLCO2A1 expression had a homozygous splice-site mutation in SLCO2A1, c.1461+1G>C (exon 7) or c.940+1G>A (exon 10). The remaining one CEAS patient with positive expression of SLCO2A1 had compound heterozygous c.664G>A and c.1807C>T mutations. Conclusions: Immunohistochemical staining for SLCO2A1 in gastroduodenal tissues obtained by endoscopic biopsy is considered useful for the distinction of CEAS from CD.