Objective:To analyze the clinical characteristics of invasive intervention-related intestinal fistula in patients with acute pancreatitis (AP).Methods:We retrospectively analyzed the clinical data of 177 moderately severe acute pancreatitis (MSAP) or severe acute pancreatitis (SAP) patients who received invasive intervention in Peking Union Medical College Hospital from January 2003 to December 2022. Patients were divided into fistula group and non-fistula group based on the presence or absence of fistula after or during receiving invasive interventions. The age, gender, etiology, systemic inflammatory response syndrome(SIRS), impairment of organ function, revised Atlanta classification, bedside index of severity of acute pancreatitis(BISAP), Balthazar CT classification, extra-pancreatic involvement and secondary infection of local complications, indications, timing and modalities of invasive interventions, length of hospitalization, length of intensive care and outcomes were recorded. The differences on clinical characteristics were compared between the two groups.Results:Intestinal fistulae were found in 21(11.9%) cases during or after invasive intervention, including 8 during or after percutaneous drainage and 13 during or after surgeries. 51 cases received endoscopic drainage or debridement and no intestinal fistula occurred after endoscopic management. Compared to patients without fistula, the median age was younger in the fistula group (36 vs 45 years, P=0.014), and the occurrence of SIRS (95.2% vs 59.6%, P=0.001), extra-pancreatic invasion (100.0% vs 67.3%, P=0.002), and secondary infection (71.4% vs 36.5%, P=0.002) were higher. Patients with fistula had a longer median length of hospitalization (71 vs 40 days, P=0.016) and intensive care (8 vs 0 days, P=0.002). All patients in the fistula group had peri-pancreatic, abdominal and retroperitoneal involvement seen on imaging or intraoperatively. The intestinal fistulae mainly occurred in the colon ( n=13, 61.9%) and the duodenum ( n=6, 28.6%). The confirmed diagnosis of fistulae was based on transfistula imaging ( n=11) or digestive tract imaging ( n=5). Among 13 cases with colonic fistulae, nonsurgical treatment was preferred in 9 cases, and surgeries of fistula repairmen or proximal ostomy were preferred in 4 cases. Among 8 cases with non-colonic fistulae, nonsurgical treatment was preferred in 7 cases, and only 1 case repaired the fistula immediately during the intraoperative detection. Conclusions:Intestinal fistula is an important complication of severe AP, and it is closely associated with invasive interventions. Improved invasive intervention strategies may help prevent intestinal fistula formation; timely and effective management of intestinal fistula may help avoid complications and shorten hospitalization.

Objective:To analyze the clinical and radiological features of patients with resected pancreatic serous cystic neoplasm (SCN).Methods:A retrospective analysis was conducted on the clinical and radiological data of 172 patients with pancreatic SCN who underwent surgical resection and were pathological confirmed at Peking Union Medical College Hospital from September 2014 to April 2022. These patients were categorized into two cohorts including 2014—2018 cohort ( n=84) and 2019—2022 ( n=88) for comparative analysis based on the operation time. Results:The radiological diagnostic accuracy for SCN was found to be notably low at 11.6%(20/172), which was mostly misdiagnosed as mucinous cystic neoplasms (86/172, 50.0%) and intraductal papillary mucinous neoplasms (35/172, 20.3%). No statistically significant variance was observed on the misdiagnosis rate between the two cohorts. There was a substantial increase of the number of lesions located in pancreatic body and tail (76.1% vs 53.6%, P=0.004) and a marked decrease in the number of those located in pancreatic head and neck (22.7% vs 39.3%, P=0.019) in 2019-2022 cohort, compared to the 2014-2018 cohort. Furthermore, there was a significant reduction in the occurrence of SCN calcification and peri-lesional venous alterations (22.8% vs 45.1%, P=0.006; 25.0% vs 46.4%, P=0.003), a decrease in the presence of fibrous scarring within SCN (31.8% vs 45.2%, P=0.070), and an increase in cases with dilatation of the upstream main pancreatic duct (28.2% vs 16.3%, P=0.065). The clinical characteristics and the rate of postoperative complications did not significantly differ between the two cohorts. Complication rates after pancreatoduodenectomy were significantly higher than those following distal pancreatectomy (46.4% vs 22.9%, P=0.010). The presence of clinical symptoms was significantly linked to the size of SCN and the expansion of the main pancreatic duct (45.4% vs 29.3%, P=0.032; 64.9% vs 31.2%, P<0.001). Conclusions:The accuracy of preoperative radiological diagnosis for SCN is still low, with a noted increase in the proportion of SCN exhibiting atypical radiological features in recent years. The frequency of postoperative complications is relatively high and does not have an obvious decreased trend.

Objective:To evaluate the diagnostic value of rapid on-site evaluation (ROSE) performed by endoscopists for solid pancreatic lesions requiring tissue for immunohistochemistry (IHC) staining with different approach of endoscopic ultrasound-guided tissue acquisition (EUS-TA).Methods:After screening 1 573 cases who underwent EUS-TA operation at the Endoscopy Center of Peking Union Medical College Hospital between August 2018 and October 2022, a total of 65 cases of solid pancreatic lesions whose diagnosis rely on IHC staining was collected and summarized with clinical data of each case. Among 65 cases, there were 46 cases of pancreatic neuroendocrine tumors (PNETs), 13 cases of pancreatic solid pseudo-papillary tumors (SPTs), and 6 cases of lymphomas and mesenchymal. Patients were categorized into ROSE group (36 cases) and non-ROSE group (29 cases) according to the presence or absence of endoscopists performed ROSE during EUS-TA operation. They were further divided into subgroups of FNA-ROSE (26 cases), FNB-ROSE (10 cases), FNA-non-ROSE (24 cases) and FNB-non-ROSE (5 cases) according to the type of EUS-TA. Diagnostic accuracy and IHC success rate were compared between different groups and subgroups. Binomial logistic multifactorial regression analysis was used to evaluate the influence of ROSE and EUS-TA type on diagnostic accuracy and IHC success rate.Results:There were no statistically significant differences between ROSE group and non-ROSE group in terms of age, gender, bilirubin level, CA19-9 level, lesion site, lesion size, composition ratio of diagnosis, and surgical rate. The differences in mean size of lesions, needle gauge, location of puncturation, and number of needle pass between subgroups were not statistically significant. The diagnostic accuracy was 88.9% in ROSE group and 79.3% in non-ROSE group, and the difference between the two groups was statistically significant ( P=0.023). The diagnostic accuracy of FNA-ROSE group was higher than that of FNA-non-ROSE group (88.5% vs 75.0%), but the difference was not statistically significant ( P>0.100). The differences in diagnostic accuracy and success rate of IHC between FNB-ROSE group and FNB-non-ROSE group were not statistically significant. Binomial logistic multifactorial regression analysis did not reveal any independent influences on diagnostic accuracy. Conclusions:ROSE performed by endoscopists improved diagnostic accuracy of EUS-TA in solid pancreatic lesions requiring IHC staining, and therefore is potentially valuable for improving the diagnostic efficiency of EUS-TA for such diseases.

Objective:To explore the clinical characteristics and outcomes of type 2 autoimmune pancreatitis (AIP) and compare with type 1 AIP.Methods:Clinical data of the patients diagnosed with type 2 AIP by the International Consensus on diagnostic criteria of AIP at Peking Union Medical College Hospital from January 2001 to December 2022 were retrospectively analyzed, and type 1 AIP patients diagnosed in Peking Union Medical College Hospital from January 1985 to December 2016 were collected as controls. The clinical symptoms, treatments and follow-ups were analyzed.Results:A total of 25 patients with type 2 AIP were included, of which 16 cases (64.0%) were pathologically confirmed cases (13 cases by endoscopic ultrasound puncture, 2 cases by surgery, and 1 case by interventional puncture), and 9 cases (36.0%) were suspected. The average age of onset was 40 years old. Most patients ( n=23, 92.0%) had abdominal pain along with emaciation to a various degree. Among them, 3 cases primarily presented as acute pancreatitis. Two cases were diagnosed after surgery for pancreatic masses. Eighteen cases were complicated with inflammatory bowel disease, including 16 cases with ulcerative colitis, one case with Crohn's disease, and one case with indeterminate colitis. All patients had typical imaging manifestations, including 13 cases (52.0%) with diffuse pancreatic enlargement, 12 cases (48.0%) with focal or multifocal pancreatic lesions, and 5 cases (20.0%) with simultaneous focal pancreatic masses and diffuse enlargement. All patients had normal serum IgG4 levels, anti-neutropil cytoplasmic antibodies (ANCA) positivity rate was 35.3% (6/17), and anti-nuclear antibody (ANA) positivity rate was 29.2% (7/24). Two surgical patients recovered well after surgery, and the other patients all achieved clinical and imaging relief after hormone therapy, and no recurrence was seen during follow-up. Compared with type 1 AIP, type 2 AIP had younger onset age, main manifestation as abdominal pain without jaundice, rare involvement with extra-pancreatic organs, the lesions mainly located in the intestine and normal IgG4 level with statistically significant differences. The recurrence rate of type 2 AIP was lower than that of type 1 AIP (0 vs 16%). Conclusions:Type 2 AIP has different clinical characteristics from type 1 AIP. Due to the lack of specific serum markers, the diagnosis is more difficult. It responds well to glucocorticoids and has a low recurrence rate.

Objective:To analyze clinical characteristics of primary pancreatic lymphoma (PPL) patients.Methods:Clinical features of 22 patients diagnosed as PPL admitted to Peking Union Medical College Hospital from January 2002 to May 2023 were analyzed retrospectively.Results:The median age was 56.4±13.3 years. The median time from onset to diagnosis was 1.0 (1.0, 3.0) months. The main clinical manifestations were abdominal pain (15/22), weight loss (14/22) and jaundice (10/22). Elevated lactate dehydrogenase (LDH) was observed in 15/20 (75%) patients. Only 2 (2/9, 22.2%) patients had increased CA199 levels and 2 (2/9, 22.2%) patients had increased CEA levels. The maximum tumor diameter was 5.0 (3.8, 6.9) cm. Contrast-enhanced CT mostly showed low enhancement lesions. Major pancreatic duct dilatation were rare on CT scan (4/20). Fifteen patients were confirmed by pancreatic pathology, of which 8 were obtained by surgery, 4 were obtained by CT or ultrasound-guided percutaneous biopsy, and 3 were obtained by EUS-FNA. The main pathological type was diffuse large B-cell lymphoma (14/22). 19 patients received chemotherapy, and 6 patients died with a median follow-up of 5.0 (1.5, 35.5) months.Conclusions:PPL is rare and easy to be misdiagnosed. Elevated LDH levels, normal tumor markers, and non-dilatation of main pancreatic duct are important diagnostic clues. It is important to obtain pathology by EUS-FNA and other methods for definite diagnosis.

Objective:To investigate the clinical value of Tyro3/Axl/Mertk (TAM) receptor tyrosine kinase and ligands in severity evaluation for acute pancreatitis (AP).Methods:The peripheral blood and clinical data of 27 patients with AP admitted in the Department of Gastroenterology of Shanghai General Hospital from February 2020 to July 2022 were prospectively selected. The patients were divided in to mild AP group (MAP, n=13), moderately severe AP (MSAP, n=10) and severe AP group (SAP, n=4) according to the 2012-revised Atlanta classification for AP. Another 10 healthy normal subjects were selected as the control group. The general information, biochemical indicators and blood cell analysis of the patients were recorded, and the levels of serum Gas6, protein S and soluble Axl (sAxl) were measured by ELISA. Linear regression equations were used to analyze the correlation of serum Gas6, protein S and sAxl levels with the white blood cell (WBC) counts, neutrophil percentages, lymphocyte percentages, and monocyte percentages of each group, and to assess the clinical value of Gas6, protein S and sAxl in predicting the severity of AP patients. Results:Compared with the control group, the serum Gas6 level [(31.3±13.0)ng/ml vs (21.2±2.6)ng/ml], protein S level [(24.4±11.3)μg/ml vs (17.7±3.4)μg/ml], and sAxl level [(9.0±4.4)ng/ml vs (6.6±1.3)ng/ml] were significantly higher in the AP group. The Gas6 level was significantly higher in the SAP group (54.1±13.7 ng/ml) than in the MAP group (31.0±9.4 ng/ml) and the MSAP group (25.2±8.9 ng/ml), and the differences were statistically significant (all P value <0.05). The Gas6 level was significantly positively correlated with the WBC count ( r=0.1733) and neutrophils percentage ( r=0.4424), and negatively correlated with lymphocyte percentage(r=-0.363), with statistically significant differences (all P value <0.05). The levels of protein S and sAXL were positively correlated WBC count and neutrophil percentage, and negatively correlated with monocyte percentage and lymphocyte percentage, but the differences were not statistically significant. Conclusions:The serum levels of Gas6 increase significantly with the severity grading of AP, which may serve as a relatively good predictor for the early severity assessment of AP.

More and more studies suggest that targeting neuronal antibodies,particularly anti-Hu antibody,can cause various degrees of damage to central nervous system and/or enteric nervous system and affect the occurrence,progression,and prognosis of related diseases.Therefore,elucidating the mechanisms of anti-Hu antibody-induced nervous system injury and its relevance to diseases is of significant importance for individualized diagnosis and treatment.This article reviewed the associations between anti-Hu antibody and paraneoplastic gastrointestinal dysmotility,chronic intestinal pseudo-obstruction,and irritable bowel syndrome,as well as the mechanisms of neuronal damage caused by anti-Hu antibody.

Objective To investigate the safety and effectiveness of colon polypectomy in patients taking antithrombotic drugs.Methods Polyps treated with endoscopic polypectomy at the Department of Gastroenterology,Fu Wai Hospital,Chinese Academy of Medical Sciences,from August 2022 to August 2023 were retrospectively analyzed for the site of polyp,postoperative delayed hemorrhage,perforation,and the completeness of resection,specimen retrieval,and the occurrence of postoperative ischemic events.Results A total of 103 polyps were included in the study,which were divided into two groups according to whether the diameter of the polyp was＞10 mm(87 cases in the small polyp group vs 16 cases in the large polyp group),and there was no statistically significant difference between the two groups in terms of the site of the polyp,its morphology,the type of antithrombotic drug taken,the rate of curative resection,the rate of postoperative hemorrhagic events,and the incidence of postoperative ischemic events;the large polyp group chose more often to undergo EMR treatment(small polyp group vs.large polyp group,4.6％vs.45.5％,P=0.004);postoperative pathology was more adenomatous polyps in the large polyp group(small polyp group vs.large polyp group,77.0％vs.93.8％,P=0.027).Conclusion Endoscopic polypectomy can be used safely and effectively in patients taking antithrombotic drugs.

The importance of question bank construction in medical education has been well proved.However,there are still some weaknesses in the clinical teaching assessment question bank,including the inconsistency be-tween assessment and clinical practice,the lack of coherence in question bank updates,and the mismatch be-tween proposition and student learning stage.To address these issues,this article explores a teaching model which connects flipped classroom with student independent proposition and analyzes the advantages of applying flipped classroom to question bank construction.The connection between the two effectively established a regular updating mechanism for question banks,thus improve the construction of question banks in current medical education.It may support the capacity building of students' self-oriented and regulated learning and improve the quality of teaching assessment.

Objective:To explore the clinical and genetic characteristics of patients with Ehlers-Danlos syndrome (EDS) and gastrointestinal involvement.Methods:We retrospectively collected the clinical data of patients with EDS and gastrointestinal involvement from the electronic medical records at Peking Union Medical College Hospital (PUMCH) from January 2003 to September 2023. Additionally, we conducted a systematic review by searching cases with EDS and gastrointestinal involvement in PubMed, Embase, Web of Science, and the Cochrane Library databases from January 2000 to September 2023.Results:Ninety-four patients with EDS and gastrointestinal involvement were retrieved, including five patients from PUMCH and 89 patients from 80 published articles. The average age of patients was (29±14) years. The most common manifestation of gastrointestinal involvement was gastrointestinal perforation ( n=46, 48.9%), followed by functional gastrointestinal symptoms ( n=33, 35.1%), and digestive arterial disorders ( n=10, 10.6%). The most common clinical subtype was vascular-EDS (vEDS) ( n=50, 53.2%) followed by hypermobile-EDS (hEDS) ( n=20, 21.3%). The most frequent genetic mutation occurred in the COL3A1 gene ( n=30, 31.9%). Among patients with vEDS, gastrointestinal manifestations included gastrointestinal perforation ( n=33, 66.0%), arterial lesions ( n=9, 18.0%), and functional gastrointestinal symptoms ( n=7, 14.0%). Among patients with hEDS, gastrointestinal manifestations included functional gastrointestinal symptoms ( n=18, 90.0%), visceral prolapse ( n=3, 15.0%) and intestinal volvulus ( n=1, 5.0%). Conclusions:The most common subtypes of gastrointestinal involvement in EDS were vEDS and hEDS. Patients with hEDS mainly presented with functional gastrointestinal symptoms, whereas those with vEDS primarily showed gastrointestinal perforation and digestive arterial disorders.