Endoscopic ultrasound-guided pancreatic sampling for the histopathological diagnosis of autoimmune pancreatitis.

Autoimmune pancreatitis (AIP), which is characterized by pancreatic enlargement and irregular narrowing of the main pancreatic duct, is difficult to differentiate from malignancy. The irregular narrowing of the pancreatic duct, which can be detected via endoscopic retrograde cholangiopancreatography, is a characteristic feature of AIP; however, distinguishing between localized AIP and pancreatic cancer based on pancreatic duct imaging is difficult. This study overviews the efficacy of endoscopic ultrasound (EUS)-guided pancreatic sampling for the histopathological diagnosis of AIP. Recent enhancements in needle biopsy methodologies and technologies have contributed to improvement in the diagnostic efficacy of this technique. The guidance provided in this study for the histological diagnosis of AIP is anticipated to further advance in the histopathological diagnosis of AIP using EUS-guided pancreatic sampling.

Assessment of the risk of disease transmission during fine-needle aspiration cytology under ultrasound guidance by visualization of droplet and aerosol formation.

PURPOSE: Fine-needle aspiration cytology (FNAC) under ultrasound guidance is clinically useful, but there is a risk of spreading infection by generating droplets of contaminated fluids during the procedure. Risk assessment to better control infection remains to be established. The aim of this study was to estimate infection risks during FNAC by visualization of droplet production and deposition using a simulation model. METHODS: The simulation comprised a puncture needle, a device for holding the needle, and a fluid specimen containing fluorescent particles as a model. Simulating each step of FNAC (removal of the inner and outer cylinder and transferring the specimen onto a glass slide), the generation and deposition of droplets were visualized using a laser. RESULTS: After removal of the inner cylinder, an aerosol of droplets in the air surrounding the needle was observed. After removal of the outer cylinder, several large droplets precipitating onto the circumjacent surface were observed. From the beginning of transferring the specimen, a large amount of sizeable droplets first moving away and then precipitating was observed, followed by the production of a cluster of fine droplets drifting and spreading through the air. CONCLUSIONS: Here, the generation of droplets at each step of FNAC, precipitation of large droplets onto the circumjacent surface, and drifting and spreading through the air of fine droplets was visualized. These results emphasize the need for precautions to prevent the transmission of infectious agents during FNAC.

Pancreatic Ductal Adenocarcinoma: Epidemiology and Risk Factors.

The number of new cases of pancreatic ductal adenocarcinoma is increasing with a cumulative total of 495,773 cases worldwide, making it the fourteenth most common malignancy. However, it accounts for 466,003 deaths per year and is the seventh leading cause of cancer deaths. Regional differences in the number of patients with pancreatic ductal adenocarcinoma appear to reflect differences in medical care, as well as racial differences. Compared to the prevalence of other organ cancers in Japan, pancreatic ductal adenocarcinoma ranks seventh based on the number of patients, eighth based on morbidity, and fourth based on the number of deaths, with a continuing increase in the mortality rate. Risk factors for developing pancreatic ductal adenocarcinoma include family history, genetic disorders, diabetes, chronic pancreatitis, and intraductal papillary mucinous neoplasms. An issue that hinders improvement in the prognosis of patients with pancreatic ductal adenocarcinoma is the development of a strategy to identify patients with these risk factors to facilitate detection of the disease at a stage when intervention will improve survival.

The Efficacy and Safety of Balloon Enteroscopy-Assisted Endoscopic Retrograde Cholangiography in Pediatric Patients with Surgically Altered Gastrointestinal Anatomy.

Balloon enteroscopy-assisted endoscopic retrograde cholangiography (BEA-ERC) is useful and feasible in adults with pancreatobiliary diseases, but its efficacy and safety have not been established in pediatric patients. We compared the success rate and safety of BEA-ERC between adults and pediatric patients. This single-center retrospective study reviewed 348 patients (pediatric: 57, adult: 291) with surgically altered gastrointestinal anatomies who underwent BEA-ERC for biliary disorders from January 2007 to December 2019. The success rate of reaching the anastomosis or duodenal papilla was significantly lower in pediatric patients than in adult patients (66.7% vs. 88.0%, p < 0.01). The clinical success rate was also significantly lower in pediatric patients (64.9% vs. 80.4%, p = 0.014). The rate of adverse events was significantly higher in pediatric patients than in adults (14.2% vs. 7.7%, p = 0.037). However, if the anastomotic sites were reached in pediatric patients, the treatment was highly successful (97.3%). The time of reaching target site was significantly longer in pediatric patients than in adult patients. This study shows that BEA-ERC in pediatric patients is more difficult than that in adult patients. However, in patients where the balloon enteroscope was advanced to the anastomosis, clinical outcomes comparable to those in adults can be achieved.

The Diagnosis of Autoimmune Pancreatitis Using Endoscopic Ultrasonography.

Autoimmune pancreatitis (AIP) is characterized by enlargement of the pancreas and irregular narrowing of the main pancreatic duct. It is often associated with IgG4-related sclerosing cholangitis (IgG4-SC), in which the bile duct narrows. Although characteristic irregular narrowing of the pancreatic duct caused by endoscopic retrograde cholangiopancreatography is noted in AIP, it is difficult to differentiate between localized AIP and pancreatic carcinoma based on imaging of the pancreatic duct. While stenosis of the bile duct in IgG4-SC is characterized by longer-length stenosis than in cholangiocarcinoma, differentiation based on bile duct imaging alone is challenging. Endoscopic ultrasound (EUS) can characterize hypoechoic enlargement of the pancreas or bile duct wall thickening in AIP and IgG4-SC, and diagnosis using elastography and contrast-enhanced EUS are being evaluated. The utility of EUS-guided fine needle aspiration for the histological diagnosis of AIP has been reported and is expected to improve diagnostic performance for AIP. Findings in the bile duct wall from endoscopic retrograde cholangiopancreatography followed by intraductal ultrasonography are useful in differentiating IgG4-SC from cholangiocarcinoma. Diagnoses based on endoscopic ultrasonography play a central role in the diagnosis of AIP.