Background/Aims: The programmed death 1 (PD-1)/programmed death-ligand 1 (PD-L1) pathway has not been fully evaluated in inflammatory bowel disease. We evaluated PD-1/PD-L1 levels in patients with ulcerative colitis (UC) and their significance in tonsil-derived mesenchymal stem cells (TMSCs) treatment. Methods: Using acute and chronic murine colitis model, we measured the PD-1 and PD-L1 levels in inflamed colonic tissues pre- and post-treatment with TMSCs. We also measured PD-1 and PD-L1 levels in colonic tissues from UC patients, compared to normal controls. Results: In the analysis using human colonic tissues, a significant increase in the levels of PD-1 and PD-L1 was observed in the colonic mucosa of patients with UC compared with normal controls (p < 0.001 and p = 0.005, respectively). When comparing the maximal disease extent, PD-L1 levels were highest in patients with proctitis (38.5 ± 46.7), followed by left-side colitis (17.5 ± 23.1) and extensive colitis (5.2 ± 8.2) (p < 0.001). In the chronic colitis model, the level of PD-L1 was decreased (p = 0.040) and the level of PD-1 increased more than in normal controls (p = 0.047). After treatment with TMSC, significant improvements were observed in body weight, disease activity index, and colon length recovery. Additionally, the levels of PD-1 and PD-L1 were recovered; PD-L1 significantly increased (p = 0.031), while the level of PD-1 decreased (p = 0.310). Conclusions The altered expression of PD-1 and PD-L1 in colonic mucosa may be a possible mechanism of UC, and T-MSC-derived PD-L1 could help suppress colitis.

Gastrointestinal (GI) bleeding is one of the most common conditions among patients visiting emergency departments in Korea. GI bleeding is divided into upper and lower GI bleeding, according to the bleeding site. GI bleeding is also divided into overt and occult GI bleeding based on bleeding characteristics. In addition, obscure GI bleeding refers to recurrent or persistent GI bleeding from a source that cannot be identified after esophagogastroduodenoscopy or colonoscopy. The small intestine is the largest part of the alimentary tract. It extends from the pylorus to the cecum. The small intestine is difficult to access owing to its long length. Moreover, it is not fixed to the abdominal cavity. When hemorrhage occurs in the small intestine, the source cannot be found in many cases because of the characteristics of the small intestine. In practice, small-intestinal bleeding accounts for most of the obscure GI bleeding. Therefore, in this review, we introduce and describe systemic approaches and examination methods, including video capsule endoscopy and balloon enteroscopy, that can be performed in patients with suspected small bowel bleeding in clinical practice.

Gastric wall abscess is a rare condition characterized by a purulent inflammatory process resulting in the formation of a pocket of pus in the stomach. As the mucosa is usually intact, it requires various tools such as endoscopic ultrasonography or computed tomography for the differential diagnosis to rule out more common subepithelial tumors. Even after the diagnosis, the treatment for gastric wall abscess was previously restricted to surgical resection in combination with antibiotics. Currently, in order to avoid unnecessary surgery, the alternative method of initial treatment with an endoscopic approach is recommended. It also helps to choose appropriate antibiotics with confirmation of the pathogen by drainage. There are few reports that describe the detailed processing of the endoscopic drainage, and there is no consensus on the treatment. The pathogens that cause gastric wall abscess are usually Streptococci, Staphylococci, and Escherichia coli. There is only one case reported to be caused by Candida albicans. This is the first report of Elizabethkingia anopheles as the pathogen of the gastric wall abscess. Here, we report a case of gastric wall abscess in a 75-year-old man, safely treated by endoscopic drainage and antibiotics, confirmed by isolating the contents of the abscess.

Catastrophic antiphospholipid syndrome is a highly fatal condition characterized by widespread thromboembolism subsequent to a triggering factor (e.g., infection, trauma, and neoplasia) in antiphospholipid antibody-positive patients. This paper reports a case of a 29-year-old male without the underlying disease who developed extensive mesenteric thromboembolism and jejunal necrosis during the treatment for acute enteritis. The patient’s condition was improved with low-molecular-weight heparin and an intravenous Ig treatment with emergency surgery. The serum antiphospholipid (anticardiolipin IgM) and lupus anticoagulant antibody tests showed positive results. Acute infectious enterocolitis is generally considered a mild disease. On the other hand, aggressive evaluation and treatment should be considered if the clinical conditions do not improve and deteriorate rapidly despite appropriate antibiotic treatment because of the possibility of acute immunological complications, such as catastrophic antiphospholipid syndrome.

Catastrophic antiphospholipid syndrome is a highly fatal condition characterized by widespread thromboembolism subsequent to a triggering factor (e.g., infection, trauma, and neoplasia) in antiphospholipid antibody-positive patients. This paper reports a case of a 29-year-old male without the underlying disease who developed extensive mesenteric thromboembolism and jejunal necrosis during the treatment for acute enteritis. The patient’s condition was improved with low-molecular-weight heparin and an intravenous Ig treatment with emergency surgery. The serum antiphospholipid (anticardiolipin IgM) and lupus anticoagulant antibody tests showed positive results. Acute infectious enterocolitis is generally considered a mild disease. On the other hand, aggressive evaluation and treatment should be considered if the clinical conditions do not improve and deteriorate rapidly despite appropriate antibiotic treatment because of the possibility of acute immunological complications, such as catastrophic antiphospholipid syndrome.

Although patients with cirrhosis are known to be in a state of “rebalance” in that pro- and anticoagulant factors increase the risk for both bleeding and thrombosis, the prevalence of portal vein thrombosis (PVT) in patients with cirrhosis can be up to 26%. Therefore, physicians should consider anticoagulation for the prevention and management of PVT in patients with cirrhosis who are at high risk of PVT. Vitamin K antagonist or low molecular weight heparin is suggested as the standard treatment for PVT in cirrhosis. With the advent of new direct-acting oral anticoagulants (DOACs), there is a paradigm shift of switching to DOACs for the treatment of PVT in patients with cirrhosis. However, the safety and efficacy of DOACs in the treatment of PVT was not well-known in patients with cirrhosis. Therefore, this review focused on the current knowledge about the efficacy, safety concerns, and hepatic metabolism of DOACs in patients with cirrhosis and PVT.

Although patients with cirrhosis are known to be in a state of “rebalance” in that pro- and anticoagulant factors increase the risk for both bleeding and thrombosis, the prevalence of portal vein thrombosis (PVT) in patients with cirrhosis can be up to 26%. Therefore, physicians should consider anticoagulation for the prevention and management of PVT in patients with cirrhosis who are at high risk of PVT. Vitamin K antagonist or low molecular weight heparin is suggested as the standard treatment for PVT in cirrhosis. With the advent of new direct-acting oral anticoagulants (DOACs), there is a paradigm shift of switching to DOACs for the treatment of PVT in patients with cirrhosis. However, the safety and efficacy of DOACs in the treatment of PVT was not well-known in patients with cirrhosis. Therefore, this review focused on the current knowledge about the efficacy, safety concerns, and hepatic metabolism of DOACs in patients with cirrhosis and PVT.

Collision tumors are extremely rare, and currently, no therapeutic protocols are established. A 64-year-old man presented to his physician with complaints of right chest and abdominal pain. The contrast-enhanced CT scan showed a mass measuring 3.6 cm around the gastric fundus. Esophagogastroduodenoscopy was performed and a semicircular longitudinal ulcerative mass was found at the distal esophagus. A mass measuring about 4 cm with central ulceration was noted at the cardia. The esophageal biopsy revealed positivity for a component of neuroendocrine carcinoma adjacent to a squamous cell carcinoma. PET-CT revealed a mass in the esophagus and cardia and several tumors in the whole liver, pancreas, and bone. The patient was finally diagnosed with a collision tumor of the esophagus with multiple metastases. In conclusion, patients with collision tumors must undergo active multidisciplinary management that will include pathologists and oncologists, who will decide on proper treatment strategies.

BACKGROUND/AIMS: Endoscopic ultrasonography (EUS) is the most efficient imaging modality for gastric subepithelial tumors (SETs). However, abdominopelvic computed tomography (APCT) has other advantages in evaluating the characteristics, local extension, or invasion of SETs to adjacent organs. This study aimed to compare the diagnostic ability of EUS and APCT based on surgical histopathology results.METHODS: We retrospectively reviewed data from 53 patients who underwent both EUS and APCT before laparoscopic wedge resection for gastric SETs from January 2010 to December 2017 at a single institution. On the basis of histopathology results, we assessed the diagnostic ability of the 2 tests.RESULTS: The overall accuracy of EUS and APCT was 64.2% and 50.9%, respectively. In particular, the accuracy of EUS vs. APCT for the diagnosis of gastrointestinal stromal tumors (GISTs), leiomyomas, and ectopic pancreas was 83.9% vs. 74.2%, 37.5% vs. 0.0%, and 57.1% vs. 14.3%, respectively. Most of the incorrect diagnoses with EUS involved hypoechoic lesions originating in the fourth echolayer, with the most common misdiagnosed lesions being GISTs mistaken for leiomyomas and vice versa.CONCLUSIONS: APCT showed a lower overall accuracy than EUS; however, APCT remains a useful modality for malignant/potentially malignant gastric SETs.
Diagnosis ; Endosonography ; Gastrointestinal Stromal Tumors ; Humans ; Leiomyoma ; Pancreas ; Retrospective Studies

Cases of cytomegalovirus (CMV) infection are rare, and this infection is commonly asymptomatic in immunocompetent patients. Here, we report a pathologically proven case of CMV infection in gastric ulcers in an immunocompetent patient. A 35-year-old man visited our hospital for a surveillance esophagogastroduodenoscopy. Except fatigue, he had no other symptoms. Laboratory data showed that his white cell count was 9.28×10³/µL with 60.1% lymphocytes. However, aspartate transaminase and alanine aminotransferase levels were elevated. Esophagogastroduodenoscopy revealed multiple gastric ulcers that were healing. Two endoscopic biopsies were performed to obtain specimens at the ulcer base. Histological examination and immunohistochemistry confirmed CMV infection; subsequently, we decided that the best option was observation without medication. He revisited a month later, and the ulcers had disappeared.
Adult ; Alanine Transaminase ; Aspartate Aminotransferases ; Biopsy ; Cell Count ; Cytomegalovirus Infections ; Cytomegalovirus ; Endoscopy, Digestive System ; Fatigue ; Humans ; Immunohistochemistry ; Lymphocytes ; Stomach Ulcer ; Ulcer