Impact of endoscopic ultrasound-guided tissue acquisition on prognosis and peritoneal lavage cytology in resectable or borderline resectable pancreatic ductal adenocarcinoma.

OBJECTIVES: This study aimed to evaluate the clinical impact of preoperative endoscopic ultrasound-guided tissue acquisition (EUS-TA) on the prognosis and incidence of positive peritoneal lavage cytology (PLC) during laparotomy or staging laparoscopy in patients with resectable (R) or borderline resectable (BR) pancreatic ductal adenocarcinoma (PDAC). METHODS: We retrospectively collected data from patients diagnosed with body and tail PDAC with/without EUS-TA at our hospital from January 2006 to December 2021. RESULTS: To examine the effect of EUS-TA on prognosis, 153 patients (122 in the EUS-TA group, 31 in the non-EUS-TA group) were analyzed. There was no significant difference in overall survival between the EUS-TA and non-EUS-TA groups after PDAC resection (P = 0.777). In univariate and multivariate analysis, preoperative EUS-TA was not identified as an independent factor related to overall survival after pancreatectomy [hazard ratio 0.96, 95 % confidence interval (CI) 0.54-1.70, P = 0.897]. Next, to examine the direct influence of EUS-TA on the results of PLC, 114 patients (83 in the EUS-TA group and 31 in the non-EUS-TA group) were analyzed. Preoperative EUS-TA was not statistically associated with positive PLC (odds ratio 0.73, 95 % CI 0.25-2.20, P = 0.583). After propensity score matching, overall survival and positive PLC were the same in both groups. CONCLUSIONS: EUS-TA had no negative impact on postoperative survival and PLC-positive rates in R/BR PDAC.

Recent advances of endoscopic retrograde cholangiopancreatography using balloon assisted endoscopy for pancreaticobiliary diseases in patients with surgically altered anatomy: Therapeutic strategy and management of difficult cases.

Endoscopic retrograde cholangiopancreatography (ERCP) is an endoscopic modality established for diagnosis and treatment of pancreaticobiliary diseases. However ERCP in patients with surgically altered anatomy (SAA) has been difficult, and more invasive therapies have been primarily selected. The development of balloon assisted endoscopes (BAEs) innovatively facilitated ERCP in such patients. Recent advances of BAEs and other devices greatly contributed to increasing success of ERCP using BAEs (BAE-ERCP). Furthermore, interventions using Endoscopic Ultrasound (EUS-intervention) have been reported to be useful for pancreaticobiliary diseases in patients with SAA, which provide more options for endoscopic therapies and are also expected as a rescue therapy for difficult cases of BAE-ERCP. In order to thoroughly complete endoscopic treatment for pancreaticobiliary diseases with SAA, it is important to standardize the BAE-ERCP procedures based on the features of respective endoscopes and to establish a strategy for endoscopic treatment which includes analysis of BAE-ERCP difficult cases and selection of cases for rescue therapy. In addition, it is essential to be acquainted with the characteristics of possible adverse events of the procedure and to be able to deal with them for safe accomplishment of endoscopic treatment.

Magnetic resonance cholangiopancreatography findings in early chronic pancreatitis diagnosed according to the Japanese Diagnostic Criteria.

OBJECTIVES: It is important for diagnosing early chronic pancreatitis (CP), which may be improved by therapeutic intervention. We aimed to examine the pancreatic ductal changes on magnetic resonance cholangiopancreatography (MRCP) in patients with early CP defined by the Japanese Diagnostic Criteria. METHODS: This retrospective study included patients suspected early CP and performed both endoscopic ultrasonography (EUS) and MRCP from January 2010 to August 2018. We assessed the diameter of the main pancreatic duct (MPD) and the number of irregularly dilated duct branches using MRCP imaging in early CP. RESULTS: We enrolled 165 patients and 25 patients (15%) fulfilled the diagnostic criteria for early CP. Irregular dilatation of ≥ 3 duct branches on MRCP was more often observed in early CP compared to non-early CP (P = 0.004), although MPD diameter was comparable (2.06 mm in early CP vs. 1.96 in non-early CP, P = 0.698). The sensitivity and specificity were 45% and 74%, respectively. The prevalence of positive MRCP findings in patients with ≥ 2 positive EUS findings was higher than that in patients with 1 positive EUS finding (P = 0.08) and in patients without an EUS finding (P < 0.001). There was no difference in the average diameter of MPD. CONCLUSION: Patients with early CP often exhibit alteration in duct branches and not in MPD in addition to parenchymal alteration. Both pancreatic parenchyma and duct branches might need to be evaluated by EUS and MRCP.

Extracellular vesicles microRNA analysis in type 1 autoimmune pancreatitis: Increased expression of microRNA-21.

BACKGROUND: The molecular basis of type 1 autoimmune pancreatitis (AIP) remains unclear. Recent attention on the role of extracellular vesicles microRNA (EV miRNA) in immune homeostasis has prompted us to perform an extensive miRNA screening of serum-derived EV in AIP. METHODS: EV miRNA expression was analyzed using microarrays in AIP, chronic pancreatitis (CP), and healthy adult (HC) samples (n = 10 from each group). Differences in signals, > 3 or <1/3 times, represented significant differences in expression. Another cohort of AIP (n = 14), CP (n = 10), and HC (n = 10) samples of EV miRNA was analyzed using reverse-transcription polymerase chain reaction (RT-PCR). miRNA expression in pancreatic tissues was evaluated using in situ hybridization (ISH) in three additional subjects from each group. RESULTS: Signals of eight miRNAs (miR-659-3p, -27a-3p, -99a-5p, -21-5p, -205-5p, -100-5p, -29c-3p, and -125b-1-3p) were significantly higher, while those of two miRNAs (miR-4252 and -5004-5p) were significantly lower in AIP than in HC. EV miR-21-5p was significantly up-regulated in AIP than in HC (P = 0.035) and CP (P = 0.048). The number of miR-21-5p positive inflammatory cells was significantly elevated in AIP than in CP (P = 0.014). CONCLUSIONS: Circulating EVs exhibited altered miRNA expression patterns with elevated miR-21-5p in AIP when compared with those in HC and CP. miR-21-5p was highly expressed in pancreatic inflammatory cells in AIP. Our data suggests that miR-21-5p may be involved in the regulation of effector pathways in the pathophysiology of AIP, thus differentiating AIP from CP.

Histological diagnosis and grading of pancreatic neuroendocrine tumor by endoscopic ultrasound-guided fine needle biopsy using a 25-gauge needle with a core trap: A multicenter prospective trial.

OBJECTIVES: Preoperative grading of pancreatic neuroendocrine tumors (PanNET) is challenging. The aim of this study was to prospectively evaluate the use of a 25-gauge needle with a core trap for diagnosis and grading of PanNET. METHODS: This multicenter prospective trial was registered with the University Hospital Medical Information Network (UMIN000021409). Consecutive patients with suspected PanNET between June 2016 and November 2017 were enrolled. All patients underwent endoscopic ultrasound-guided fine needle biopsy (EUS-FNB) using a 25-gauge needle with a core trap. Samples obtained after the first needle pass were used for central pathological review. EUS-FNB was evaluated in terms of (i) technical success rate, (ii) adequacy for histological evaluation, (iii) complication rate during the procedure, and (iv) concordance between PanNET grading on EUS-FNB and that after analysis of the resected tumor. RESULTS: Fifty-two patients were enrolled. Of the 36/52 patients who underwent surgical resection, 31 were finally diagnosed with PanNET and were eligible for analysis. The technical success rate of EUS-FNB was 100%. The rate of adequacy for histological evaluation was 90.3%. There were no complications related to EUS-FNB. The concordance rate between PanNET grading on EUS-FNB and that after analysis of the resected tumor was 82.6% (95% confidence interval = 61.22-95.05, P = 0.579). CONCLUSIONS: EUS-FNB using a 25-gauge needle with a core trap is feasible, providing histological samples are of sufficient quality for diagnosis and grading of PanNET.

Evaluation of complications after endoscopic retrograde cholangiopancreatography using a short type double balloon endoscope in patients with altered gastrointestinal anatomy: a single-center retrospective study of 1,576 procedures.

BACKGROUND AND AIM: Endoscopic retrograde cholangiopancreatography (ERCP) using balloon-assisted endoscope such as double-balloon endoscope is even effective for patients with surgically altered anatomy. Yet comprehensive studies on complications of ERCP using balloon-assisted endoscope have not been made. We analyzed the characteristics and the causes of complications of ERCP using double-balloon endoscope (DB-ERCP) procedures and aimed to suggest effective managements. METHODS: A total of 1576 procedures of DB-ERCP in 714 patients with surgically altered gastrointestinal anatomy in our hospital were evaluated retrospectively using a statistic analysis. RESULTS: The overall complication occurrence rate was 5.8%. By type of complications are perforation 3.2%, mucosal laceration 0.5%, hemorrhage 1.0%, pancreatitis 0.6%, respiratory disorder 0.4%, and others 0.2%. By type of surgical reconstruction methods were Roux-en-Y reconstruction with choledocho-jejunal anastomosis 4.2%, Roux-en-Y reconstruction without choledocho-jejunal anastomosis 6.7%, pancreaticoduodenectomy 4.5%, pylorus preserving pancreaticoduodenectomy 4.2%, Billroth II gastrectomy (B-II) 11.6%, and other reconstruction method (others) 7.4%. The contributing factors calculated by a multivariate analysis were B-II (odds ratio: 1.864, 95% confidence interval: 1.001-3.471, P = 0.050) and the presence of naïve papilla (odds ratio: 3.268, 95% confidence interval: 1.426-7.490, P = 0.005). CONCLUSIONS: DB-ERCP is a safe method with a total complication rate of 5.8% that could be considered within an acceptable range. The most common complication was the injury of the digestive tract such as perforation. Affecting risk factors for complications were B-II and the presence of naïve papilla. DB-ERCP procedures should be performed carefully of these factors.

Clinicopathological and immunological features of follicular pancreatitis - a distinct disease entity characterised by Th17 activation.

AIM: Follicular pancreatitis is a recently recognised, distinct clinicopathological entity characterised by the presence of many intrapancreatic lymphoid follicles with reactive germinal centres. However, the clinicopathological and immunological features and causes have not yet been established. We assessed the clinicopathological and immunological profiles of patients with follicular pancreatitis who underwent surgery. METHODS AND RESULTS: This study included three patients with pancreatic masses (age range = 62-75 years; women:men: 1:2). A histopathological study of the resected pancreatic masses revealed abundant lymphoid follicles with reactive germinal centres in both periductal regions and diffusely within the parenchyma. No storiform fibrosis, obliterative phlebitis or granulocytic epithelial lesions were observed. The immunohistochemical examination revealed an IgG4/IgG-positive plasma cell ratio <30% in all patients. Podoplanin (Th17 marker)-expressing lymphocytes were present in the lymphoid follicles of those with follicular pancreatitis, whereas these were absent in normal lymph nodes and in lymphoid follicles of those with IgG4-related autoimmune pancreatitis (AIP). An RNA digital counting assay clearly demonstrated that the expression counts of 20 genes, including dendritic cells and lymphoid follicles markers, and related cytokines were significantly higher in follicular pancreatitis than in IgG4-related AIP (P < 0.01). The expressions of CCR6 and IL23A, which are genes related to Th17, were high. CONCLUSIONS: This study shows that follicular pancreatitis is a histopathologically and immunologically distinct disease entity of pancreatitis and is characterised by upregulated Th17 expression.

Morphological and immunohistochemical comparison of intrapancreatic nerves between chronic pancreatitis and type 1 autoimmune pancreatitis.

OBJECTIVES: The abdominal pain associated with chronic pancreatitis (CP) may be related to the increased number and size of intrapancreatic nerves. On the other hand, patients with type 1 autoimmune pancreatitis (AIP) rarely suffer from the pain syndrome, and there are no previous studies concerning the histopathological findings of intrapancreatic nerves in patients with type 1 AIP. The current study is aimed at investigating the differences in the histopathological and immunohistochemical findings of intrapancreatic nerves in patients with CP and type 1 AIP. METHODS: Neuroanatomical differences between CP and type 1 AIP were assessed by immunostaining with a pan-neuronal marker, protein gene product 9.5 (PGP9.5). The number (neural density) and area (neural hypertrophy) of PGP9.5-immunopositive nerves were quantitatively analyzed. Furthermore, the expression of nerve growth factor (NGF), and a high affinity receptor for NGF, tyrosine kinase receptor A (TrkA), was assessed by immunohistochemistry. RESULTS: Both neural density and hypertrophy were significantly greater in pancreatic tissue samples from patients with CP than those with normal pancreas or type 1 AIP. NGF expression was stronger in type 1 AIP than in CP, whereas TrkA expression in type 1 AIP was poorer than in CP. CONCLUSIONS: Although CP and type 1 AIP are both characterized by the presence of sustained pancreatic inflammation, they are different in terms of the density and hypertrophy of intrapancreatic nerve fibers. It is possible that this may be related to the difference in the activity of the NGF/TrkA-pathway between the two types of pancreatitis.

Utility of newly developed short-type double-balloon endoscopy for endoscopic retrograde cholangiography in postoperative patients.

BACKGROUND AND AIM: The utility of conventional short-type double-balloon endoscopy (DBE) for pancreatobiliary disease in patients with postoperative anatomy had been widely acknowledged and accepted. However, some technical difficulties yet remained. In an attempt to solve these problems, the new short-type DBE (N-short DBE) was uniquely designed for therapeutic endoscopic retrograde cholangiography (ERC) in postoperative patients. The aim of this study was to evaluate the usefulness of N-short DBE for ERC in postoperative patients. METHODS: From August 2015 to April 2016, ERC using N-short DBE (DB-ERC) was performed in 100 postoperative patients (112 procedures). We retrospectively studied the success rate of reaching the blind end, the median time to reach the blind end, the diagnostic success rate, the therapeutic success rate, the median time to complete ERC-related interventions, the overall success rate, the median time to complete DB-ERC, and adverse events. RESULTS: The success rate of reaching the blind end was 99.1%. The median time to reach the blind end was 10 min (interquartile range [IQR], 6-19 min). The diagnostic success rate was 98.2%. The therapeutic success rate was 100%. The median time to complete ERC-related interventions was 36 min (IQR, 22-62 min). The overall DB-ERC success rate was 97.3%. The median time to complete DB-ERC was 54 min (IQR, 37-73 min). The occurrence of adverse events was 2.7%. CONCLUSIONS: The N-short DBE for ERC in postoperative patients is useful and safe. DB-ERC is promising therapeutic modality in such patients and should be selected as the first-line policy.

A body mass index ≥25 kg/m2 is associated with a poor prognosis in patients with acute pancreatitis: a study of Japanese patients.

BACKGROUND: In Asian population, there is limited information on the relevance between obesity and poor outcomes in acute pancreatitis (AP). The objective of this study was to examine the clinical impact of obesity based on body mass index (BMI) on prognosis of AP in Japanese patients. METHODS: A total of 116 patients with AP were enrolled in this study. Univariate and multivariate logistic regression analyses were performed to examine relations between BMI and patients' outcomes. Additionally, to investigate whether including obesity as a prognostic factor improved the predictive accuracy of a Japanese prognostic factor score (PF score), a receiver-operating characteristic (ROC) curve analysis of mortality was conducted. RESULTS: Multiple logistic regression analyses revealed that BMI =25 kg/m2 was associated with a significant higher mortality [odds ratio (OR)=15.8; 95% confidence interval (CI): 1.1-227; P=0.043]. The area under the ROC curve (AUC) for the combination of PF score and BMI =25 kg/m2 (AUC=0.881; 95% CI: 0.809-0.952) was higher than that for the PF score alone (AUC=0.820; 95% CI: 0.713-0.927) (P=0.034). CONCLUSIONS: The negative impact of a high BMI on the prognosis of AP was confirmed in a Japanese population. Including BMI =25 kg/m2 as an additional parameter to PF score enhanced the predictive value of the PF score for AP-related mortality.

Diagnostic and Therapeutic Endoscopic Retrograde Cholangiography Using a Short-Type Double-Balloon Endoscope in Patients With Altered Gastrointestinal Anatomy: A Multicenter Prospective Study in Japan.

OBJECTIVES: To evaluate the utility and safety of a short-type double-balloon endoscope (DBE) in the treatment of biliary disease in patients with surgically altered gastrointestinal (GI) anatomy. METHODS: This study was conducted as a multicenter, single-arm, prospective trial at five tertiary academic care centers and three community-based hospitals in Japan. Consecutive patients with biliary disease with altered GI anatomy were prospectively included in this study. RESULTS: A total of 311 patients underwent double-balloon endoscopic retrograde cholangiography (ERC). The success rate of reaching the target site, the primary end point, was 97.7% (95% confidence interval (CI): 95.4-99.1). The success rate of biliary cannulation and contrast injection of the targeted duct, the secondary end point, was 96.4% (95% CI: 93.6-98.2), and the therapeutic success rate was 97.9% (95% CI: 95.4-99.2). Adverse events occurred in 33 patients (10.6%, 95% CI: 7.1-14.0) and were managed conservatively in all patients with the exception of 1 in whom a perforation developed, requiring emergency surgery. CONCLUSIONS: ERC using a short-type DBE resulted in an excellent therapeutic success rate and a low rate of adverse events. This treatment can be a first-line treatment for biliary disease in patients with surgically altered GI anatomy.

Histologic diagnosis of pancreatic masses using 25-gauge endoscopic ultrasound needles with and without a core trap: a multicenter randomized trial.

BACKGROUND AND STUDY AIMS: Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) with 25-gauge needles yields small volume samples that are mainly processed for cytology. Using 25-gauge needles with a core trap may overcome this limitation. This trial compared 25-gauge needles with and without a core trap in terms of their ability to obtain histologic samples from solid pancreatic masses. PATIENTS AND METHODS: Consecutive patients with solid pancreatic masses who presented to eight Japanese referral centers for EUS-FNA in April - September 2013 were randomized to undergo sampling with a 25-gauge needle with a core trap (ProCore) or a standard 25-gauge needle. Tissue samples were fixed in formalin and processed for histologic evaluation. For the purpose of this study only samples obtained with the first needle pass were used for comparison of: (i) accuracy for the diagnosis of malignancy, (ii) rate of samples with preserved tissue architecture adequate for histologic evaluation, and (iii) sample cellularity. RESULTS: A total of 214 patients were enrolled. Compared to the first pass with a standard needle (n = 108), the first pass with the ProCore needle (n = 106) provided samples that were more often adequate for histologic evaluation (81.1 % vs. 69.4 %; P = 0.048) and had superior cellularity (rich/moderate/poor, 36 %/27 %/37 % vs. 19 %/26 %/55 %; P = 0.003). There were no significant differences between the two needles in sensitivity (75.6 % vs. 69.0 %, P = 0.337) and accuracy (79.2 % vs. 75.9 %, P = 0.561) for the diagnosis of malignancy. CONCLUSIONS: In patients with solid pancreatic masses, a 25-gauge EUS-FNA needle with a core trap provides histologic samples of better quality than a standard 25-gauge needle. There was no difference in accuracy for the diagnosis of malignancy between the needles. CLINICAL TRIAL NUMBER: UMIN000010021.

Fluorescence cytology with 5-aminolevulinic acid in EUS-guided FNA as a method for differentiating between malignant and benign lesions (with video).

BACKGROUND: EUS-guided FNA (EUS-FNA) has been increasingly performed to obtain specimens for the pathological evaluation of patients with GI and pancreaticobiliary masses as well as lymphadenopathies of unknown origin. Photodynamic diagnosis by using 5-aminolebulinic acid (ALA) has been reported to be useful for enabling the visual differentiation between malignant and normal tissue in various cancers. OBJECTIVE: To evaluate the diagnostic accuracy of fluorescence cytology with ALA in EUS-FNA. DESIGN: A prospective study. SETTING: A single center. PATIENTS: A total of 28 consecutive patients who underwent EUS-FNA for the pathological diagnosis of a pancreaticobiliary mass lesion or intra-abdominal lymphadenopathy of unknown origin. INTERVENTIONS: Patients were orally administered ALA 3 to 6 hours before EUS-FNA. The sample was obtained via EUS-FNA for fluorescence cytology and conventional cytology. A single gastroenterologist performed the fluorescence cytology by using fluorescence microscopy after the procedure, independently of the conventional cytology by pathologists. MAIN OUTCOME MEASUREMENTS: The accuracy of fluorescence cytology with ALA in the differentiation between benign and malignant lesions by comparing the results of fluorescence cytology with the final diagnosis. RESULTS: Of the 28 patients included in the study, 22 were considered as having malignant lesions and 6 patients as having benign lesions. Fluorescence cytology could correctly discriminate between benign and malignant lesions in all patients. Therefore, both the sensitivity and specificity of fluorescence cytology were 100% in our study. LIMITATIONS: Fluorescence cytology was performed by only 1 gastroenterologist with a small number of patients. CONCLUSION: Fluorescence cytology with ALA in EUS-FNA may be an effective and simple method for differentiating between benign and malignant lesions.

IgG4 cholangiopathy: current concept, diagnosis, and pathogenesis.

IgG4 related cholangiopathy, a distinctive type of cholangitis of unknown origin, is characterized by increased serum levels of IgG4, massive infiltration of IgG4-positive plasma cells with storiform fibrosis and/or obliterative phlebitis in the thickened bile duct wall, and good response to steroids. Patients with IgG4-cholangiopathy are frequently associated with autoimmune pancreatitis; IgG4-cholangiopathy is recognized as a biliary manifestation of IgG4-related disease. This condition can be diagnosed by a combination of imaging, serology, histopathology, and steroid responsiveness; however, cholangiographic features are often difficult to differentiate from primary sclerosing cholangitis, pancreatic cancer, or cholangiocarcinoma. The Japanese clinical diagnostic criteria for IgG4-related sclerosing cholangitis established in 2012 are useful in the diagnosis of IgG4-cholangiopathy. Although the precise pathogenic mechanism remains unclear, the development of IgG4-cholangiopathy may involve: susceptible genetic factors, abnormal innate and acquired immunity, decreased naïve regulatory T cells, and specific B cell responses. Further studies on genetic backgrounds, disease specific antigens, and the role of IgG4 are necessary to clarify the pathogenesis.

Relationship between autoimmune pancreatitis and pancreatic cancer: a single-center experience.

OBJECTIVES: Ordinary chronic pancreatitis (CP), such as alcoholic CP, is well established to have the increased risk for pancreatic cancer (PaC), nevertheless an association between autoimmune pancreatitis (AIP) and PaC is still unknown. The aims of this study are to examine the frequency of patients who developed PaC during follow-up after being diagnosed with type 1 AIP and to compare the incidence rate of PaC between patients with type 1 AIP and CP. METHODS: Sixty-three patients with type 1 AIP and 41 patients with CP were enrolled. We examined development of PaC during follow-up from their clinical records. RESULTS: The mean follow-up period was 62.4 months in AIP group and 49.2 months in CP group. The occurrence of PaC was observed in 3 patients with AIP during the mean follow-up period of 94.7 months (range, 31-186), whereas a single CP patient developed PaC 38 months after CP diagnosis. The incident rate of PaC during follow-up was comparable between the 2 groups [4.8% (3/63) in type 1 AIP group vs. 2.4% (1/41) in CP group]. In all of 3 AIP patients who developed accompanying PaC, the clinical remission of AIP was achieved with maintenance steroid therapy, when tumors were discovered. In the histological examination of one surgical patient with PaC, lymphoplasmacytic infiltration in storiform fibrosis with abundant IgG4-positive cell infiltration was observed around the PaC area. CONCLUSIONS: Similar to patients with ordinary CP, surveillance for development of PaC is needed at regular interval during follow-up in AIP patients.

The role of CD19+ CD24high CD38high and CD19+ CD24high CD27+ regulatory B cells in patients with type 1 autoimmune pancreatitis.

BACKGROUND: Patients with type 1 autoimmune pancreatitis (AIP) have several immunologic and histologic abnormalities. It is known that depletion of B cells by rituximab is effective for treatment of IgG4-related disease (IgG4-RD) such as type 1 AIP, suggesting that B cells may be a key player in IgG4-RD. However, the role of regulatory B cells (Bregs) in type 1 AIP is unclear, and the objective of this paper is to clarify the role of Bregs in the pathophysiology of type 1 AIP by analyzing circulating Bregs. METHOD: We recruited 21 patients with type 1 AIP as determined by the International Consensus Diagnostic Criteria for AIP (ICDC). No patients received corticosteroid treatments. For comparison, we recruited 14 patients with chronic pancreatitis (CP), 20 patients with pancreatic cancer, and 25 healthy subjects as controls. We analyzed Bregs as CD19+ CD24high CD38high and CD19+ CD24high CD27+ from peripheral blood by flow cytometry. RESULTS: In peripheral blood, CD19+ CD24high CD38high Bregs were significantly increased in type 1 AIP patients compared with CP, pancreatic cancer, and healthy controls. Although not significant different, CD19+ CD24high CD27+ Bregs of type 1 AIP were decreased compared to those of other groups. IL-10(+) B cells were not significantly different from type 1 AIP patients and healthy controls. In untreated type 1 AIP patients, the number of CD19+ CD24high CD38high Bregs and IgG4 were not correlated. CONCLUSIONS: Our data suggested that CD19+ CD24high CD38high Bregs seemed to increase reactively to suppress the disease activity, and are consistent with the hypothesis that CD19+ CD24high CD27+ Bregs might be involved in the development of type 1 AIP, although it still remains unclear whether the decrease of CD19+ CD24high CD27+ cells is cause or effect of AIP.

Endoscopic approaches for pancreatobiliary diseases in patients with altered gastrointestinal anatomy.

Endoscopic treatment for pancreatobiliary diseases is less invasive than surgery and percutaneous transhepatic biliary drainage is highly beneficial to patients. The endoscopic approach is indicated for an increasing number of patients, including those who have undergone previous gastrointestinal surgery, although these patients face two major challenges. First, the endoscopic approach to the afferent loop, blind end, and the site of choledochojejunostomy is difficult with the use of a conventional endoscope because of the distance from the gastrojejunal anastomosis site, unusual anatomical features of the intestine such as its winding shape, and postoperative adhesion. Second, it is difficult to reach Vater's papilla or the site of choledochojejunostomy and to cannulate selectively into the pancreatic and/or biliary duct. The balloon-assisted endoscope (BAE), a recently developed technology, can be useful for carrying out endoscopic retrograde cholangiopancreatography (ERCP) in patients with surgically altered anatomy. ERCP using the BAE is highly effective and safe in patients with altered gastrointestinal anatomy, especially in patients with Roux-en-Y reconstruction.

Evaluation of endoscopic retrograde cholangiopancreatography using a newly developed short-type single-balloon endoscope in patients with altered gastrointestinal anatomy.

BACKGROUND AND AIM: Endoscopic approaches for pancreatobiliary diseases in patients with altered gastrointestinal anatomy had been impractical until the development of balloon-assisted endoscope (BAE) made it feasible. The aim of the present study was to evaluate the usefulness of a newly developed short-type single-balloon endoscope (s-SBE) for endoscopic retrograde cholangiopancreatography (ERCP) in patients with altered gastrointestinal anatomy. METHODS: From March 2013 to November 2013, s-SBE-assisted ERCP was done in our hospital in 26 postoperative patients who had surgically altered anatomy. We retrospectively evaluated the success rate of reaching the blind end, the mean time required to reach the blind end, the diagnostic success rate, the therapeutic success rate, the mean procedure time, and complications. RESULTS: The success rate of reaching the blind end was 92.3%. The mean time required to reach the blind end was 25.3 min. The diagnostic success rate was 91.7%. The diagnostic success rate for naïve papilla was 75%. The mean procedure time was 56.0 min. The success rate of overall s-SBE-assisted ERCP was 84.6%. The complication rate was 3.8%. CONCLUSION: Diagnostic and therapeutic ERCP using a newly developed s-SBE is sufficiently effective.

Transcutaneous monitoring of partial pressure of carbon dioxide during endoscopic retrograde cholangiopancreatography using a double-balloon endoscope with carbon dioxide insufflation under conscious sedation.

BACKGROUND AND AIM: A double-balloon (DB) endoscope can be selectively inserted into the afferent loop to carry out endoscopic retrograde cholangiopancreatography (ERCP) in patients with surgically altered anatomy, allowing various types of endoscopic treatments for pancreaticobiliary diseases to be successfully carried out. In order to make such a lengthy procedure more comfortable and safe, sedatives and carbon dioxide (CO2 ) insufflation are widely used for gastrointestinal endoscopy. However, these techniques can increase the risk of CO2 retention. Recently, a new sensor for transcutaneous measurement of partial pressure of carbon dioxide (PCO2 ) has been introduced. The aim of the present study was to evaluate the changes in transcutaneous PCO2 (PtcCO2 ) during DB-ERCP with CO2 insufflation under conscious sedation and assess any complications related to sedation and CO2 insufflation. METHODS: A total of 312 patients underwent DB-ERCP with CO2 insufflation at our hospital between March 2009 and December 2012. The patients were moderately sedated using midazolam with or without pentazocine. PtcCO2 was measured by a non-invasive sensor throughout DB-ERCP in all patients. RESULTS: The mean peak PtcCO2 during the procedure was significantly higher than the mean PtcCO2 value before and after DB-ERCP. Body mass index, procedure time and dose of pentazocine were significantly higher in the CO2 retention group (peak PtcCO2 ≥ 50 mmHg). CO2 narcosis was observed in one case. CONCLUSIONS: DB-ERCP with CO2 insufflation under conscious sedation might have the potential to increase the risk of CO2 retention. Hence, non-invasive and continuous PtcCO2 measurement is useful for early detection of hypercapnia.