Role of advanced endoscopy in the management of inflammatory digestive diseases (pancreas and biliary tract)

The progress of endoscopic diagnosis and treatment for inflammatory diseases of the biliary tract and pancreas have been remarkable. Endoscopic ultrasonography (EUS) and EUS-elastography are used for the diagnosis of early chronic pancreatitis and evaluation of endocrine and exocrine function in chronic pancreatitis. Notably, extracorporeal shock wave lithotripsy and electrohydraulic shock wave lithotripsy have improved the endoscopic stone removal rate in patients for whom pancreatic stone removal is difficult. Studies have reported the use of self-expanding metal stents for stent placement for pancreatic duct stenosis and EUS-guided pancreatic drainage for refractory pancreatic duct strictures. Furthermore, EUS-guided drainage using a double-pigtailed plastic stent has been performed for the management of symptomatic pancreatic fluid collection after acute pancreatitis. Recently, lumen-apposing metal stents have led to advances in the treatment of walled-off necrosis after acute pancreatitis. EUS-guided biliary drainage is an alternative to refractory endoscopic biliary drainage and percutaneous transhepatic biliary drainage for the treatment of acute cholangitis. The placement of an inside stent followed by switching to uncovered self-expanding metal stents in difficult-to-treat cases has been proposed for acute cholangitis by malignant biliary obstruction. Endoscopic transpapillary gallbladder drainage is an alternative to percutaneous transhepatic gallbladder drainage for severe and some cases of moderate acute cholecystitis. EUS-guided gallbladder drainage has been reported as an alternative to percutaneous transhepatic gallbladder drainage and endoscopic transpapillary gallbladder drainage. However, it is important to understand the advantages and disadvantages of each drainage method and select the optimal drainage method for each case.

Symptomatic duodenal intramural hematoma caused by weight training: a report of two cases

Symptoms of traumatic duodenal intramural hematoma, a rare disease caused by trauma, blood disease, or antithrombotic therapy, can include abdominal pain. Case 1 is that of a 35-year-old man at a gym who dropped a 100 kg barbell on his abdomen. It was diagnosed as a duodenal obstruction caused by a traumatic intestinal wall hematoma. In Case 2, a 16-year-old male adolescent performing deadlift training at a gym had subsequent abdominal pain. It was diagnosed as intestinal wall hematoma. Both patients improved with conservative treatment. Malignancy is sometimes suspected from imaging findings. Detailed patient history and imaging studies can avoid unnecessary surgery.

Treatment of endoscopic ultrasound-guided coil deployment for isolated gastric varices using 0.035-inch hydrocoil: Experience of three cases

Endoscopic ultrasound (EUS)-guided coil deployment (EUS-coiling) has been newly developed for treating isolated gastric varices (iGV). This report describes three cases of EUS-coiling for iGV using a 0.035-inch hydrocoil (Azur; Terumo Corp., Tokyo, Japan). When used for EUS-coiling, this hydrocoil provides the following benefits: Its electrically detachable system allows pull back. It has smooth and dense deployment. Moreover, it has a strong blood-flow blocking effect because of its long length and large diameter with internal swelling functions of the hydrogel. Technical success of coiling was achieved in all cases. After coiling, additional treatments such as cyanoacrylate and sclerosant injection were performed as deemed appropriate. All iGVs were obliterated successfully. No adverse event occurred during the procedure or during the mean follow-up of six months. Our findings indicate that this 0.035-inch hydrocoil can be used to treat iGV safely and effectively.

Acute Pancreatitis Leading to the Diagnosis of Presymptomatic Crohn's Disease: A Pediatric Case Report

A 14-year-old boy presented with fever and abdominal pain and was diagnosed with acute pancreatitis based on computed tomography findings. The patient had neither diarrhea nor bloody stool but was diagnosed with microcytic anemia. Endoscopic examination revealed a cobblestone pattern and longitudinal ulcer scars in the jejunum. However, no abnormal findings were observed in the ileum or colon. Endoscopic ultrasound-guided fine-needle aspiration was performed from pancreatic body-tail. Pathological examination revealed no evidence of autoimmune pancreatitis (AIP). It was unclear from pathological examination whether idiopathic pancreatitis had self-limitedly improved or whether it was AIP localized to the pancreatic head. The patient was diagnosed with asymptomatic small-bowel Crohn's disease (CD), which may have been two unrelated events of acute pancreatitis. Acute pancreatitis may precede a diagnosis of inflammatory bowel disease. CD with only jejunal involvement (Montreal classification L4) is extremely rare, and we were able to diagnose it early.

Investigating COVID-19 Pandemic Effects on Acute Pancreatitis Development-From the Perspective of Alcohol Sales (Consumption) in a Japanese Regional Hospital

[Aim and Background] People's lifestyles changed considerably due to the coronavirus disease 2019 (COVID-19) pandemic. The number of patients with acute pancreatitis (AP) can be expected to decrease as alcohol consumption decreases. This study was conducted to assess COVID-19 pandemic effects on AP patients in a Japanese regional hospital. [Methods] Based on the first and second states of emergency declarations in Tochigi Prefecture, the survey periods were set as follows: period A, 16 April-14 May; period B, 15 May-13 January; period C, 14 January-7 February; and period D, 8 February-15 April. Using data acquired in 2017, 2018, 2019, and 2020, we retrospectively reviewed the number of patients admitted to our hospital with a diagnosis of AP, and their clinical characteristics. [Results] According to a National Tax Agency survey, the average alcohol sales per adult in Tochigi Prefecture were 71.3 L in 2017 before the pandemic, and 64.0 L in 2021 under the pandemic. The number of AP patients in 2020 was 38% lower than in 2017. Comparing 2017 with 2020, the number of alcoholic AP patients was lower in 2020 (p = 0.007). [Conclusions] The findings suggest that COVID-19-pandemic-related lifestyle changes contributed to the decrease in AP patients.

Proposal and Validation of New Diagnostic Criteria for Diagnostic Weights of Endoultrasonographic Findings for Early Chronic Pancreatitis

[Background and study aim] A commonly applied method for diagnosing chronic pancreatitis (CP) uses endoscopic ultrasonography (EUS), assigning weights to each EUS diagnostic finding. It is the Rosemont classification (RC). In 2019, to improve EUS diagnostic specificity, Japanese diagnostic criteria for early chronic pancreatitis (ECP) were revised. Nevertheless, the criteria use no weighting of EUS diagnostic findings, as the RC does. This study was undertaken to propose diagnostic criteria that would weight each EUS finding of ECP and that would be more specific than the RC. [Methods] By EUS of the pancreas, 773 patients underwent detailed observation from January 2018 to March 2019 at our institution. An expert finalized all cases when patients were diagnosed. Using data from the medical records, 97 consecutive patients with EUS diagnostic findings of ECP based on the Japanese diagnostic criteria of ECP2009 (JDCECP2009) were selected. The definition under the RC of "Indeterminate for CP" was equivalent to ECP. Each case was diagnosed using (1) JDCECP2009 and (2) the Japanese diagnostic criteria of ECP2019 (JDCECP2019). Moreover, the four diagnostic EUS findings in JDCECP2019 were applied to the RC, weighted (modified-JDCECP2019), and subsequently compared with the earlier diagnostic criteria. As Modified-JDCECP2019, we suggested (3) RC-A-the current four items scored related to the RC, and (4) RC-B-the five items scored by dividing lobularity with and without honeycombing. [Results] Diagnoses produced based on each criterion were normal: ECP = (1) 20:77, (2) 46:51, (3) 52:42, and (4) 60:35. [Conclusions] Modified-JDCECP2019 may provide EUS diagnoses for ECP with higher specificity.

Guide Wire Selection (Straight vs. Angled) in Endoscopic Retrograde Cholangiopancreatography Using a Normal Contrast Catheter Performed by a Trainee: A Single-Center Prospective Randomized Controlled Cross-Over Study

INTRODUCTION

Wire-guided cannulation (WGC) during endoscopic retrograde cholangiopancreatography (ERCP) is a selective biliary cannulation technique aimed at improving the successful selective biliary cannulation rate and reducing the rate of post-ERCP pancreatitis (PEP) incidence. This study aimed to evaluate the effectiveness of angled-tip guidewires (AGW) vs. straight-tip guidewires (SGW) for biliary cannulation via WGC by a trainee.

METHODS

We conducted a prospective, single-center, open-labeled, randomized, and controlled trial. Fifty-seven patients were enrolled in this study and assigned randomly to two groups (Group A to S and Group S to A). In this study, we started selective biliary cannulation via WGC with an AGW or an SGW for 7 min. If cannulation was unsuccessful, the other guidewire was used, and cannulation was continued for another 7 min (cross-over method).

RESULTS

The selective biliary cannulation success rate over 14 min was significantly higher with an AGW compared with an SGW over 14 min (57.8% vs. 34.3%, p = 0.04) and for the second 7-min segment (36.4% vs. 0%, p = 0.04). No significant difference was found for adverse events such as pancreatitis between the two guidewires.

CONCLUSIONS

Our results suggest that an AGW is recommended for WGC performed by a trainee.

Size reduction of gastric fundic gland polyposis by de-escalation of acid-suppressive therapy

The patient, a 73-year-old woman, had been taking acid-suppressive therapy for refractory reflux esophagitis for 10 years. A potassium-competitive acid blocker was administered to strengthen acid-suppressive therapy for worsening symptoms of gastroesophageal reflux disease. Esophagogastroduodenoscopy showed an increase in the number and size of fundic gland polyposis (FGPs). When acid-suppressive therapy was changed from potassium-competitive acid blocker to proton pump inhibitor, the FGPs showed reduced size 1 year later. Furthermore, when acid-suppressive therapy was changed from proton pump inhibitor to histamine-2 receptor antagonist, FGPs were even smaller after 1 and 2 years. The patient, who had no flare-up of gastroesophageal reflux disease symptoms, continues to be treated medically with histamine-2 receptor antagonist. This case report describes changes in endoscopic findings of a patient with FGPs caused by acid-suppressive therapy for refractory gastroesophageal reflux disease.

Diagnosing chronic pancreatitis by endoscopic ultrasound assessing the association between ultrasound and pathological findings: A narrative review

Endoscopic ultrasound (EUS) is widely recognized for its non‐invasiveness and for its usefulness in chronic pancreatitis (CP) diagnosis, including early CP. Although it is desirable to obtain a definitive diagnosis of CP by tissue sampling with EUS‐guided fine needle aspiration, histopathological changes in CP are heterogeneous in terms of the extent and the distribution of lesions. Therefore, histopathological diagnosis of appropriate tissue sampling by EUS‐fine needle aspiration is expected to be difficult. Furthermore, it is virtually impossible to match EUS images with pathological sections, making direct contrast between EUS findings and pathology difficult. This narrative review presents a discussion of the diagnosis of CP/early CP by EUS, particularly assessing the association between ultrasound and pathological findings. Recently, the histological corroboration and correlation of EUS findings related to CP have been clarified by surgical specimens, including those obtained from animal studies. Furthermore, remarkable advances have occurred in the objective and quantitative diagnosis of pancreatic fibrosis by EUS‐elastography. Future technological advances in EUS are expected to improve the accuracy of diagnosis of pancreatic fibrosis at earlier stages.

A case in which the tip of a plastic stent placed to prevent recurrence of walled‐off necrosis penetrated the bile duct and formed a stent–stone complex

A woman in her 60s underwent endoscopic sphincterotomy for choledocholithiasis. Unfortunately, post‐endoscopic retrograde cholangiopancreatography pancreatitis occurred. In addition, huge walled‐off necrosis (WON) appeared as a late complication. For the infected WON, endoscopic ultrasound‐guided fistuloplasty and endoscopic necrosectomy were performed, and a double pigtail plastic stent (PS) (7Fr, 7 cm) was placed to prevent a recurrence. Plain computed tomography conducted two years later showed that the stent implanted for WON had deviated. The distal end of the stent was found to have migrated into the bile duct. In addition, common bile duct stones with stents as nuclei were observed. Upon performing endoscopic retrograde cholangiography, it was revealed that the stent tip perforated the distal bile duct just above the papilla. After removal of the stent using grasping forceps, we made an incision between the duodenal – bile duct fistula and bile duct orifice using a sphincterotome. Then, the stone was removed by a balloon catheter. Although such late adverse events are rare occurrences, placement of long‐term PS after treatment of WON should be followed up regularly with imaging examination, and if there is no recurrence for several months, removal of the PS at that point may be considered.

Making Hematochezia of Unknown Origin Known: A Retrospective Analysis

INTRODUCTION

Hematochezia is observed frequently in daily practice. However, natural hemostasis often prevents identification of the bleeding source during observations. This study was conducted to clarify risk factors related to rebleeding in hematochezia patients without an identified cause of bleeding.

METHODS

We analyzed patients who were admitted to Dokkyo Medical University Hospital during April 1, 2009, through March 31, 2015, with the chief complaint of hematochezia. Main outcome measures included the rebleeding rate and the period until rebleeding in hematochezia patients without an identified bleeding source.

RESULTS

We selected 159 patients for analyses. Rebleeding was observed in 46 (28.9%) of 159 patients. The median period until first rebleeding was 166 days (2-3,046 days). Univariate analysis indicated that risk factors for rebleeding were male gender (p = 0.029), higher age (p = 0.023), antithrombotic medicines (p = 0.047), lower hemoglobin on admission (p = 0.024), and the presence of diverticula (p = 0.002). Multivariate analysis indicated the presence of diverticula (p = 0.023) and male gender (p = 0.043) as rebleeding risk factors.

DISCUSSION/CONCLUSION

In patients with hematochezia of unknown origin, risk factors for rebleeding indicated in this study, especially the presence of diverticula and male gender, should be given particular attention by physicians.

Natural History of Small Gastric Subepithelial Lesions Less than 20 mm: A Multicenter Retrospective Observational Study (NUTSHELL20 Study)

BACKGROUND AND AIM

Small gastric subepithelial lesions (SELs) are sometimes encountered in daily esophagogastroduodenoscopy (EGD) practice, but whether once-annual or twice-annual endoscopy can provide sufficient follow-up remains unclear. Because follow-up based on small-SEL characteristics is important, this study clarified the natural history of gastric SELs less than 20 mm.

METHODS

This retrospective multicenter observation study conducted at 24 Japanese hospitals during April 2000 to March 2020 examined small gastric SELs of ≤20 mm diameter. The primary outcome was the rate of size increase of those SELs detected using EGD, with growth times assessed irrespective of SEL pathological diagnoses.

RESULTS

We examined 824 cases with tumors of 1-5 mm diameter in 298 (36.2%) cases, 6-10 mm in 344 (41.7%) cases, 11-15 mm in 112 (13.6%) cases, and 16-20 mm in 70 (8.50%) cases. An increase of small gastric SELs was observed in 70/824 patients (8.5%). The SELs larger than 6 mm increased, even after 10 years. No-change and increasing groups had no significantly different malignant findings at diagnosis. In cases of gastrointestinal stromal tumors (GISTs), internal cystic change in endoscopic ultrasound (EUS) is a risk factor for an increased tumor size. The predictive tumor growth cutoff size at initial diagnosis was 13.5 mm.

CONCLUSIONS

Small gastric SELs less than 20 mm have an approximately 8.5% chance of increase. Predictive markers for GIST growth are tumor size ≥13.5 mm and internal cystic change in EUS.

The impact of endoscopic sphincterotomy incision size on common bile duct stone recurrence: A propensity score matching analysis

BACKGROUND/PURPOSE

The aim of this study is to clarify the relation between the incision size for endoscopic sphincterotomy (EST) and common bile duct stone (CBDS) recurrence.

METHODS

Patients who underwent elective endoscopic treatment for CBDS between January 2013 and December 2017 were enrolled, excluding those who met the exclusion criteria. The clinical characteristics were investigated using propensity score matching analysis.

RESULTS

A total of 243 patients were investigated. Propensity scores were calculated using multinomial logistic regression with five relevant variables (age, gender, follow-up time, maximum stone size, and bile duct diameter), which led to extraction of 188 cases to compose cohorts of the small and medium EST incision groups. The CBDS recurrence rate was 17.0% in the small incision group and 6.4% in the medium incision group. Multivariate analysis identified the medium incision as an independent predictor of CBDS recurrence (hazard ratio 0.350, 95% confidence interval 0.133-0.922, P = .034). The CBDS non-recurrence rate of the medium incision group was significantly higher than that of the small incision group (log-rank test P = .019).

CONCLUSIONS

Our findings suggest that the CBDS recurrence rate was lower in EST with medium incision size than with small incision size.

Measuring optimal ultrasound speed using endoscopic ultrasound in patients with chronic pancreatitis, including early stage

OBJECTIVES

Ultrasound speed (USS) correction improves image quality by estimating the optimal USS correcting the deviation from a predetermined USS. This study assessed USS differences between chronic pancreatitis (CP), early CP (ECP), and normal pancreas when using endoscopic ultrasound (EUS). The usefulness of measuring optimal USS was evaluated for patients with CP, including early stage patients.

METHODS

This study enrolled 116 consecutive patients for whom USS was measured using an EUS system. The USS correction principle is generation of a B-mode image by changing the USS in all ranges while correcting the delay in the received data. Final diagnoses were made according to the Japanese diagnostic criteria for CP in 2019. They were classified as CP, ECP, or normal. We compared USS applied for these three groups.

RESULTS

The medians and ranges of USS values for patients in the normal, ECP, and CP groups were 1506.0 (1407-1600) m/s, 1580.0 (1520-1630) m/s, and 1574.0 (1537-1610) m/s, respectively. The USS values of the ECP and CP groups were significantly higher than those of the normal group (P < 0.001). Analyses of the receiver operating characteristic curve in the normal pancreas, ECP, and CP revealed the area as 0.957, with specificity and sensitivity of 95.9% and 87.5%, respectively, using the USS of 1535 m/s as a cut-off.

CONCLUSION

Measurement of USS might be particularly useful for distinguishing between normal and ECP imaging.

Salvage Endoscopic Submucosal Dissection for Local Recurrence of Superficial Esophageal Squamous Cell Cancer after Photodynamic Therapy

Photodynamic therapy is useful as organ-preservation salvage therapy for residual recurrence of esophageal squamous cell carcinoma after chemoradiation therapy. However, the high residual recurrence rate of photodynamic therapy poses a problem. We herein report a patient who underwent photodynamic therapy for recurrence of superficial esophageal squamous cell carcinoma after chemoradiation therapy. The patient later exhibited another episode of recurrence of superficial esophageal squamous cell carcinoma, and R0 curative resection was obtained with endoscopic submucosal dissection. This suggests that endoscopic submucosal dissection may be an effective treatment option that can achieve R0 resection even for residual superficial cancer after salvage photodynamic therapy.

The Risk Factors for Progression to Chronic Pancreatitis in Patients with Past-History of Acute Pancreatitis: A Retrospective Analysis Based on Mechanistic Definition

Background: According to the mechanistic definition, the history of acute pancreatitis (AP) is a risk factor for chronic pancreatitis (CP). However, the etiology and severity of previous AP involved in the progression to CP have not been clarified. Here, we investigated risk factors for the progression to CP in patients with past-history of AP. Methods: Sixty-four patients with AP who were followed-up for at least two years at our institution between April 2009 and March 2017 were enrolled. The multivariate analysis was performed based on the risk factors extracted by univariate analysis. Results: Among the 64 patients, 13 patients (20.3%) progressed to CP (PCP group), while 48 did not (non-PCP group). Regarding the etiology of AP, rate of alcohol AP was significantly higher in the PCP group (76.9% vs. 33.3%, p = 0.003). In univariate analysis, smoking, number of previous AP, and alcohol consumption and drinking habits (Alcohol Use Disorders Identification Test-Concise; AUDIT-C) were identified as factors associated with progression to CP. Furthermore, multivariate analysis showed that AUDIT-C ≥ 6 points (male) and 4 points (female) after AP was a significant risk factor for CP (p = 0.003). Conclusions: Our results indicated that AUDIT-C ≥ 6 points (male) and 4 points (female) after AP was a risk factor in the process of progression to CP in patients with past-history of AP.

A Case of Stevens–Johnson Syndrome Complicated with Multimatrix System Mesalamine in Ulcerative Colitis

A 41-year-old man was treated with prednisolone (PSL) and multimatrix (MMX) mesalamine for remission induction therapy of ulcerative colitis. PSL was tapered due to successful remission induction treatment. During the treatment course, ocular foreign body sensation, eyelid swelling, ocular conjunctiva hyperemia, facial redness and swelling, watery nasal discharge, stomatitis, anal pain, and reddish puffiness on the bilateral dorsum of the hands appeared, and he was diagnosed with Stevens–Johnson syndrome (SJS). SJS was improved by PSL treatment and intravenous immunoglobulin. MMX mesalamine was the causative agent by drug-induced lymphocyte stimulation test. This is the first reported case of SJS with MMX mesalamine.

Whole circumferential endoscopic submucosal dissection of superficial adenocarcinoma in long-segment Barrett's esophagus: A case report

BACKGROUND

Esophageal adenocarcinoma (EAC) derived from long-segment Barrett’s esophagus (LSBE) is extremely rare in Asia. LSBE-related EAC is often difficult to diagnose in the horizontal extent. If the tumor has spread throughout the LSBE, whole circumferential endoscopic submucosal dissection (ESD) should be performed, which is difficult to complete safely. Additionally, whole circumferential ESD can bring refractory postoperative stenosis. We hereby report a case of EAC involving the whole circumference of the LSBE, achieving complete endoscopic removal without complications.

CASE SUMMARY

An 85-year-old man with the chief complaint of dysphagia underwent esophagogastroduodenoscopy. We suspected a flat-type cancerous lesion that extended the whole circumference of the LSBE (C 3.5, M 4.0) using narrow-band imaging magnification endoscopy (NBI-M). We achieved circumferential en bloc resection of the lesion safely with special ESD techniques. Histology of the ESD specimens demonstrated that the superficial EAC extended the whole circumference of the LSBE, and papillary or well-differentiated tubular adenocarcinoma was confined in the lamina propria mucosa showing a vertical negative margin. To prevent post-ESD stenosis, we performed endoscopic local injection of steroids, followed by oral administration of steroids. There was no evidence of esophageal refractory stenosis or tumor recurrence 30 mo after ESD. In summary, we experienced a rare case of LSBE-related EAC. The horizontal tumor extent was accurately diagnosed by NBI-M. Additionally, we achieve whole circumferential ESD safely without postoperative refractory stenosis.

CONCLUSION

NBI-M, ESD, and steroid therapy enabled the curative resection of superficial full circumferential LSBE-related EAC without refractory postoperative stenosis.

Analysis of Endoscopic Evaluation Reliability for Ulcerative Colitis in Histological Remission

The Mayo endoscopic subscore (MES) is a major endoscopic scoring system used to assign a status of mucosal inflammation and disease activity to patients with ulcerative colitis (UC). Using interobserver reliability (IOR), this study clarified the difficulties for endoscopic observers imposed by MES parameters used for the endoscopic evaluation of UC in histological remission. First, 42 endoscopists of four observer groups examined each MES parameter, which were evaluated from endoscopically obtained images of 100 cases as Grade 0 or 1 of the Nancy histological index of histopathological inflammation. Then, IOR was assessed using multiple κ statistics for each finding of MES. The results showed that IOR among all the observers was slight or fair for all the parameters, indicating a low IOR. The experts of the UC practice group had "moderate" or higher IOR for seven of the nine parameters, whereas "slight" or "fair" results were found for all parameters by the trainee group. The IOR for each MES parameter was calculated separately for the observer groups. All the groups showed "slight" or "fair" for "Erythema" and "Decreased vascular pattern". Large differences between the endoscopists were found in the IOR for the MES parameters in UC in histological remission. Even among UC practice experts, the IOR was low for "Erythema" and "Decreased vascular pattern".

Development of biliary stent applying the antibacterial activity of silver: A literature review

BACKGROUND

Endoscopic transpapillary stenting is commonly performed in patients with obstructive jaundice caused by a biliary stricture. Although the plastic stent (PS) is widely used for biliary drainage because of the low-cost and easy procedure, patency is short after placement in the bile duct because of the small diameter. Dysfunction of PS is primarily caused by biliary sludge that forms as a result of bacterial adhesion and subsequent biofilm formation on the inner surface of the stent. It is well known that silver ions have excellent antibacterial activity against a wide range of microorganisms.

OBJECTIVE

This review provides an overview and perspective of the significance of silver-coated biliary stents.

METHODS

We collected literature regarding silver-coated biliary stents, reviewed the current research/development status and discussed their possible usefulness.

RESULTS

To date, several in vivo/vitro studies evaluated the patency of silver-blended or silver-coated biliary stents. These studies suggested that the silver coating on a PS was likely to prolong the patency period.

CONCLUSION

The development of biliary stents using silver is expected to prolong stent patency and prevent frequent stent replacement.

A Case of Crohn's Disease with Cardiac Tamponade Caused by Tuberculous Pericarditis: Assessment of a Rare Phenomenon

A 28-year-old woman was hospitalized for cardiac tamponade caused by tuberculous pericarditis. She was taking ustekinumab (UST) for Crohn’s disease. UST is not considered to significantly increase the risk of developing serious infections, including tuberculosis. However, there is still a risk of Mycobacterium tuberculosis reactivation. Therefore, for patients on concurrent UST and antituberculosis medication, a close collaboration among specialists in infectious diseases, cardiology, and gastroenterology is necessary.

Huge Amoebic Liver Abscess in the Left Lobe Treated by Oral Administration of Metronidazole

A man in his 60s visited a clinic with chief complaints of a fever and general malaise. Suspecting a liver abscess in the left lobe with infiltration into the subcutaneous fat tissue under the rectus abdominis muscle based on computed tomography findings, we performed fine-needle aspiration. An amoebic liver abscess was diagnosed. Remission was achieved by the oral administration of metronidazole alone without placement of a drainage tube. The results obtained in this case suggest that the first line of treatment should be a non-invasive approach with oral administration alone. Invasive intervention should then be considered depending on subsequent progress.

Interobserver Reliability of Endoscopic Ultrasonography: Literature Review

Endoscopic ultrasonography (EUS) has been applied to the diagnosis of various digestive disorders. Although it has been widely accepted and its diagnostic value is high, the dependence of EUS diagnosis on image interpretation done by the endosonographer has persisted as an important difficulty. Consequently, high interobserver reliability (IOR) in EUS diagnosis is important to demonstrate the reliability of EUS diagnosis. We reviewed the literature on the IOR of EUS diagnosis for various diseases such as chronic pancreatitis, pancreatic solid/cystic mass, lymphadenopathy, and gastrointestinal and subepithelial lesions. The IOR of EUS diagnosis differs depending on the disease; moreover, EUS findings with high IOR and those with IOR that was not necessarily high were used as diagnostic criteria. Therefore, to further increase the value of EUS diagnosis, EUS diagnostic criteria with high diagnostic characteristics based on EUS findings with high IOR must be established.

Prediction of the progression of walled-off necrosis in patients with acute pancreatitis on whole pancreatic perfusion CT

BACKGROUND/PURPOSE

This study investigated whether measuring pancreatic blood volume (PBV) on whole pancreatic perfusion computed tomography (P-CT) can predict the progression of walled-off necrosis (WON) in patients with acute pancreatitis (AP).

METHODS

A single-center, retrospective cohort study was conducted between December 2015 and December 2016. The participants were divided into two groups: 14 patients with WON and 15 patients without WON. PBV was measured within 72 hours after the diagnosis of AP, and the final diagnosis of WON was made by contrast-enhanced CT (CE-CT) or endoscopic ultrasonography (EUS) 4 weeks after the onset of AP.

RESULTS

The minimum CT value did not differ significantly between the two groups. On the other hand, the minimum PBV was significantly lower in the WON group than in the without WON group (1.4 (0.9-9.9) vs 19.8 (8.2-21.7) mL/100 mL, respectively; P = .02). The cutoff value of the minimum PBV for WON was 16.5 mL/100 mL (sensitivity 100%, specificity 67%, AUC 0.85; P = .001).

CONCLUSIONS

Whole pancreatic P-CT can evaluate pancreatic ischemia visually and quantitatively. The minimum PBV measurement on whole pancreatic P-CT within 72 hours after the diagnosis of AP contributes to the prediction of progression of WON.

Severe Acute Pancreatitis with Candida Endophthalmitis

Severe acute pancreatitis (SAP) is a risk factor for candidemia. We report a case of candida endophthalmitis in a 67-year-old man who was admitted to a hospital due to SAP with poorly controlled diabetes. After treatment for SAP, he was diagnosed with candidemia and candida endophthalmitis. We chose appropriate antifungal agents based on the results of a bacterial culture test. After treatment, the disappearance of Candida albicans (C. albicans) from the blood stream was confirmed in blood cultures. In addition, exudative plaques consistent with a fungal infection disappeared. After a diagnosis of candidemia is made, it is important to administer appropriate antifungal therapy and perform frequent ophthalmologic examinations.

[A case of rectal villous adenoma with electrolyte depletion syndrome treated with surgical resection]

A 65-year-old man was previously admitted to our university hospital thrice in the last 2 years because of acute kidney failure. This time he was admitted because of frequent diarrhea, anorexia, exacerbation of renal function, and hyponatremia. Rectal wall thickening was detected on computed tomography. Subsequently, a rectal polyp with mucous secretion was found on colonoscopy, which was further diagnosed as a subcutaneous villous adenoma on biopsy. Thus, electrolyte depletion syndrome associated with the rectal polyp was thought to be the cause of his symptoms. Finally, the patient underwent abdominoperineal resection of the rectum. Histopathologically, the rectal lesion was diagnosed as a villous/tubularadenoma without malignancy, and this is such a rare case to be reported.

Endoscopic side-by-side uncovered self-expandable metal stent placement for malignant hilar biliary obstruction

AIM

To investigate outcomes of endoscopic bilateral side-by-side placement across the papilla using 10-mm-diameter uncovered self-expandable metal stents for unresectable malignant hilar biliary obstruction.

METHODS

We retrospectively analyzed 23 patients who underwent endoscopic biliary uncovered self-expandable metal stent placement for unresectable malignant hilar biliary obstruction between January 2015 and September 2016 at our institution. We performed endoscopic side-by-side placement across the papilla using 10-mm-diameter longer-model uncovered self-expandable metal stents. Outcomes included the technical and functional success rates, recurrent biliary obstruction rate, time to recurrent biliary obstruction, reintervention rate, and incidence of adverse events other than recurrent biliary obstruction.

RESULTS

Of the 23 patients, 10 with malignant hilar biliary obstruction underwent endoscopic side-by-side uncovered self-expandable metal stent placement across the papilla (median age, 83 years; 6 men). The locations of malignant hilar biliary obstruction were Bismuth types II (n = 3), III (n = 3), and IV (n = 4). The median common bile duct diameter was 8 mm. The technical and functional success rates were 100% and 80%, respectively. Seven patients (70%) developed recurrent biliary obstruction because of stent occlusions, including early hemobilia in two patients and late tumor ingrowth in five patients. The median time to recurrent biliary obstruction was 66 (95% confidence interval: 29-483) days. Six patients (60%) required reintervention, and 1 (10%) underwent transcatheter arterial embolization for right hepatic arterial pseudoaneurysm. Early adverse events other than recurrent biliary obstruction occurred in four patients and late adverse event in one patient.

CONCLUSION

Endoscopic side-by-side placement across the papilla using 10-mm-diameter uncovered self-expandable metal stents was technically feasible for unresectable malignant hilar biliary obstruction; however, it might be better to avoid this method for patients with malignant hilar biliary obstruction because of high recurrent biliary obstruction rate and shorter time to recurrent biliary obstruction.

Safety of endoscopic sphincterotomy in patients undergoing antithrombotic treatment: a retrospective study

BACKGROUND

This study investigated the safety of endoscopic sphincterotomy in patients undergoing antithrombotic treatment.

METHODS

From January 2014 to December 2016, a single-center retrospective study was conducted. Of the 80 patients with naïve papilla receiving antithrombotic treatment who underwent endoscopic sphincterotomy, 76 patients were retrospectively analyzed. We divided the participants into two groups as follows: 45 patients who discontinued antithrombotic treatment (discontinuation group) and 31 patients who continued antithrombotic treatment (continuation group). We evaluated the safety of endoscopic sphincterotomy in patients with naïve papilla who received antithrombotic treatment.

RESULTS

The percentage of patients requiring emergency endoscopic retrograde cholangiopancreatography in the continuation group was significantly higher than that in the discontinuation group (55% vs 11%; p = 0.001). The incidence of adverse events did not differ significantly between the two groups. Neither bleeding nor perforation occurred in either group. The length of hospital stay did not differ significantly between the two groups.

CONCLUSIONS

Endoscopic sphincterotomy in patients undergoing antithrombotic treatment may be safe if the guidelines for gastroenterological endoscopy in patients undergoing antithrombotic treatment are followed.

Side-by-side partially covered self-expandable metal stent placement for malignant hilar biliary obstruction

BACKGROUND AND STUDY AIMS

 This study investigated the feasibility of side-by-side (SBS) partially covered self-expandable metal stent (PCSEMS) placement for unresectable malignant hilar biliary obstruction (MHBO).

PATIENTS AND METHODS

 We retrospectively analyzed 33 patients from a single center who underwent endoscopic biliary drainage for unresectable MHBO from July 2013 to June 2015. In all patients with bilateral obstruction during complete bilateral intrahepatic cholangiograms, we performed endoscopic SBS placement of a 6-mm diameter PCSEMS using an 8-French delivery system. All patients underwent endoscopic sphincterotomy. Generally, patients with recurrent biliary obstruction (RBO) after stent placement underwent endoscopic reintervention. Our study outcomes included the technical and functional success rates, RBO rate, time to RBO (TRBO), reintervention rate, and incidence of adverse events.

RESULTS

 Seventeen patients with unresectable MHBO during complete bilateral intrahepatic cholangiograms underwent endoscopic SBS PCSEMS placement (median age, 78 years; men, 9). Lesions were Bismuth types II (n = 10), III (n = 1), and IV (n = 6), including 10 cholangiocarcinomas, 3 gallbladder cancers, and 4 metastatic cancers. In all patients, the PCSEMS was placed across the duodenal papilla. The technical and functional success rates were 100 % and 82 %, respectively. The median procedure time was 43 minutes (interquartile range [IQR]: 36 - 52 minutes). Twelve patients had RBO (71 %), including 9 stent occlusions due to sludge and 3 stent migrations. The median TRBO was 79 days (IQR: 58 - 156 days) during the follow-up period (median 192 days [IQR: 88 - 551 days]). The median TRBO of patients with Bismuth type II lesions was significantly longer than that of patients with Bismuth types III and IV lesions (87 days [IQR: 70 - 244 days] vs. 54 days [IQR: 35 - 100 days]; P  = 0.030). Thirteen patients (76 %) required endoscopic reintervention. Endoscopic stent removal was possible in 6 patients without tumor ingrowth into the uncovered distal part of the stent. One late adverse event (≥ 31 days) occurred (cholangitis).

CONCLUSIONS

 Endoscopic SBS placement of a PCSEMS was feasible in patients with unresectable MHBO. Additionally, reinterventional stent removal was possible in the absence of tumor ingrowth.

The Prognosis of Severe Acute Pancreatitis Varies According to the Segment Presenting With Low Enhanced Pancreatic Parenchyma on Early Contrast-Enhanced Computed Tomography: A Multicenter Cohort Study

OBJECTIVE

The aim of this study was to investigate the outcomes of severe acute pancreatitis (SAP) according to the segment presenting with low enhanced pancreatic parenchyma (LEPP) on early contrast-enhanced computed tomography.

METHODS

This was a post hoc analysis of a multicenter, retrospective study conducted at 44 institutions in Japan. Patients diagnosed as having SAP according to the Japanese Severity Score between January 2009 and December 2013 were included. We compared the effect of LEPP in each segment on mortality.

RESULTS

A total of 1097 patients were assessed. The numbers of patients with LEPP in the pancreatic head (Ph), body (Pb), or tail (Pt) were 272, 273, and 204 (with some overlaps), respectively. In multivariate analysis, LEPP in Ph and Pt was significantly related to mortality (odds ratio [OR], 1.94; 95% confidence interval [CI], 1.11-3.40 [P < 0.05], for LEPP in Ph; OR, 2.44; 95% CI, 1.27-4.67 [P < 0.05], for LEPP in Pt), but LEPP in Pb was unrelated to mortality (OR, 0.70; 95% CI, 0.35-1.37; P = 0.30).

CONCLUSIONS

Presence of LEPP in Ph and Pt on early contrast-enhanced computed tomography was independently associated with increased mortality in SAP. These patients require close observation to ensure timely and adequate intervention.

Feasibility of initial endoscopic common bile duct stone removal in patients with acute cholangitis

AIM

To investigate the feasibility of initial endoscopic common bile duct (CBD) stone removal in patients with acute cholangitis (AC).

METHODS

A single-center, retrospective study was conducted between April 2013 and December 2014 and was approved by the Medical Ethics Committee at our institution. Written informed consent was obtained from each patient prior to the procedure. The cohort comprised 31 AC patients with CBD stones who underwent endoscopic biliary drainage (EBD) for naïve papilla within 48 h after AC onset. We retrospectively divided the participants into two groups: 19 patients with initial endoscopic CBD stone removal (initial group) and 12 patients with delayed endoscopic CBD stone removal (delayed group). We evaluated the feasibility of initial endoscopic CBD stone removal in patients with AC.

RESULTS

We observed no significant differences between the groups regarding patient characteristics. According to the assessments based on the Tokyo Guidelines, the AC severity of patients with initial endoscopic CBD stone removal was mild to moderate. The use of antithrombotic agents before EBD was less frequent in the initial group than in the delayed group (11% vs 58%, respectively; P = 0.004). All the patients underwent successful endoscopic CBD stone removal and adverse events did not differ significantly between the groups. The number of endoscopic retrograde cholangiopancreatography procedures was significantly lower in the initial group than in the delayed group [median (interquartile range) 1 (1-1) vs 2 (2-2), respectively; P < 0.001]. The length of hospital stay was significantly shorter for the initial group than for the delayed group [10 (9-15) vs 17 (14-20), respectively; P = 0.010].

CONCLUSION

Initial endoscopic CBD stone removal in patients with AC may be feasible when AC severity and the use of antithrombotic agents are carefully considered.

Peripancreatic Tuberculous Lymphadenitis Diagnosed via Endoscopic Ultrasound-guided Fine-needle Aspiration and Polymerase Chain Reaction

We performed endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) on a patient presenting with an asymptomatic peripancreatic mass-like lesion. The aspiration cytologic finding was class II. On positron emission tomography-computed tomography (PET-CT), there were hot spots in the left supra-clavicular lymph node and the peripancreatic lesion. A whole biopsy of the left supra-clavicular lymph node revealed tuberculous lymphadenitis. Polymerase chain reaction (PCR) using tissue obtained via EUS-FNA showed that the peripancreatic mass-like lesion was also positive for tuberculosis. We made a diagnosis of peripancreatic tuberculous lymphadenitis. In patients with enlarged lymph nodes, including those in the abdominal area, tuberculous lymphadenitis is a potential diagnosis.

Electrocautery vs non-electrocautery dilation catheters in endoscopic ultrasonography-guided pancreatic fluid collection drainage

AIM: To investigate the safety and utility of an electrocautery dilation catheter for endoscopic ultrasonography (EUS)-guided pancreatic fluid collection drainage.

METHODS: A single-center, exploratory, retrospective study was conducted between August 2010 and August 2014. This study was approved by the Medical Ethics Committee of our institution. Informed, written consent was obtained from each patient prior to the procedure. The subjects included 28 consecutive patients who underwent EUS-guided transmural drainage (EUS-TD) for symptomatic pancreatic and peripancreatic fluid collections (PFCs) by fine needle aspiration using a 19-gauge needle. These patients were retrospectively divided into two groups based on the use of an electrocautery dilation catheter as a fistula dilation device; 15 patients were treated with an electrocautery dilation catheter (electrocautery group), and 13 patients were treated with a non-electrocautery dilation catheter (non-electrocautery group). We evaluated the technical and clinical successes and the adverse events associated with EUS-TD for the treatment of PFCs between the two groups.

RESULTS: There were no significant differences in age, sex, type, location and diameter of PFCs between the groups. Thirteen patients (87%) in the electrocautery group and 10 patients (77%) in the non-electrocautery group presented with infected PFCs. The technical success rates of EUS-TD for the treatment of PFCs were 100% (15/15) and 100% (13/13) for the electrocautery and the non-electrocautery groups, respectively. The clinical success rates of EUS-TD for the treatment of PFCs were 67% (10/15) and 69% (9/13) for the electrocautery and the non-electrocautery groups, respectively (P = 0.794). The procedure time of EUS-TD for the treatment of PFCs in the electrocautery group was significantly shorter than that of the non-electrocautery group (mean ± SD: 30 ± 12 min vs 52 ± 20 min, P < 0.001). Adverse events associated with EUS-TD for the treatment of PFCs occurred in 0 patients and 1 patient for the electrocautery and the non-electrocautery groups, respectively (P = 0.942).

CONCLUSION: EUS-TD using an electrocautery dilation catheter as a fistula dilation device for the treatment of symptomatic PFCs appears safe and contributes to a shorter procedure time.

0.025-inch vs 0.035-inch guide wires for wire-guided cannulation during endoscopic retrograde cholangiopancreatography: A randomized study

AIM: To compare the clinical outcomes between 0.025-inch and 0.035-inch guide wires (GWs) when used in wire-guided cannulation (WGC).

METHODS: A single center, randomized study was conducted between April 2011 and March 2013. This study was approved by the Medical Ethics Committee at our hospital. Informed, written consent was obtained from each patient prior to study enrollment. Three hundred and twenty-two patients with a naïve papilla of Vater who underwent endoscopic retrograde cholangiopancreatography (ERCP) for the purpose of selective bile duct cannulation with WGC were enrolled in this study. Fifty-three patients were excluded based on the exclusion criteria, and 269 patients were randomly allocated to two groups by a computer and analyzed: the 0.025-inch GW group (n = 109) and the 0.035-inch GW group (n = 160). The primary endpoint was the success rate of selective bile duct cannulation with WGC. Secondary endpoints were the success rates of the pancreatic GW technique and precutting, selective bile duct cannulation time, ERCP procedure time, the rate of pancreatic duct stent placement, the final success rate of selective bile duct cannulation, and the incidence of post-ERCP pancreatitis (PEP).

RESULTS: The primary success rates of selective bile duct cannulation with WGC were 80.7% (88/109) and 86.3% (138/160) for the 0.025-inch and the 0.035-inch groups, respectively (P = 0.226). There were no statistically significant differences in the success rates of selective bile duct cannulation using the pancreatic duct GW technique (46.7% vs 52.4% for the 0.025-inch and 0.035-inch groups, respectively; P = 0.884) or in the success rates of selective bile duct cannulation using precutting (66.7% vs 63.6% for the 0.025-inch and 0.035-inch groups, respectively; P = 0.893). The final success rates for selective bile duct cannulation using these procedures were 92.7% (101/109) and 97.5% (156/160) for the 0.025-inch and 0.035-inch groups, respectively (P = 0.113). There were no significant differences in selective bile duct cannulation time (median ± interquartile range: 3.7 ± 13.9 min vs 4.0 ± 11.2 min for the 0.025-inch and 0.035-inch groups, respectively; P = 0.851), ERCP procedure time (median ± interquartile range: 32 ± 29 min vs 30 ± 25 min for the 0.025-inch and 0.035-inch groups, respectively; P = 0.184) or in the rate of pancreatic duct stent placement (14.7% vs 15.6% for the 0.025-inch and 0.035-inch groups, respectively; P = 0.832). The incidence of PEP was 2.8% (3/109) and 2.5% (4/160) for the 0.025-inch and 0.035-inch groups, respectively (P = 0.793).

CONCLUSION: The thickness of the GW for WGC does not appear to affect either the success rate of selective bile duct cannulation or the incidence of PEP.

Evaluation of diagnostic cytology via endoscopic naso-pancreatic drainage for pancreatic tumor

AIM: To evaluate the usefulness of cytology of the pancreatic juice obtained via the endoscopic naso-pancreatic drainage tube (ENPD-C).

METHODS: ENPD was performed in cases where a diagnosis could not be made other than by using endoscopic retrograde cholangiopancreatography and in cases of pancreatic neoplasms or cystic tumors, including intraductal papillary mucinous neoplasm (IPMN) suspected to have malignant potential. 35 patients (21 males and 14 females) underwent ENPD between January 2007 and June 2013. The pancreatic duct was imaged and the procedure continued in one of ENPD-C or ENPD-C plus brush cytology (ENPD-BC). We checked the cytology result and the final diagnosis.

RESULTS: The mean patient age was 69 years (range, 48-86 years). ENPD-C was performed in 24 cases and ENPD-C plus brush cytology (ENPD-BC) in 11 cases. The ENPD tube was inserted for an average of 3.5 d. The final diagnosis was confirmed on the basis of the resected specimen in 18 cases and of follow-up findings at least 6 mo after ENPD in the 18 inoperable cases. Malignancy was diagnosed in 21 cases and 14 patients were diagnosed as having a benign condition. The ratios of class V/IV:III:II/I findings were 7:7:7 in malignant cases and 0:3:11 in benign cases. The sensitivity and specificity for all patients were 33.3% and 100%, respectively. The cytology-positive rate was 37.5% (6/16) for pancreatic cancer. For IPMN cases, the sensitivity and specificity were 33% and 100%, respectively.

CONCLUSION: Sensitivity may be further increased by adding brush cytology. Although we can diagnosis cancer in cases of a positive result, the accuracy of ENPD-C remains unsatisfactory.

Stable deletions arising in the readthrough region of Soil-borne wheat mosaic virus RNA2 define the 5' limit of the functional promoter for the p19 subgenomic RNA

The appearance of de novo deletion mutations in the readthrough (RT) region (nucleotide positions 861-2591) downstream of the capsid protein (CP) gene of a Japanese strain of Soil-borne wheat mosaic virus RNA2 was examined using infectious transcripts. Mutant RNA2s with different deletions predominated in independent serial passage experiments but all best-adapted mutants retained the 3'-terminal portion of the RT gene in frame with the CP gene. The longest best-adapted mutation deleted the 1434 nucleotides between positions 1061 and 2494. When the RT protein was truncated by insertion of a termination codon plus an additional nucleotide to give a +1 frame-shift, after serial passages the progeny viruses regained the ability to express the C-terminal region of RT by an internal deletion. The 5' terminus of the p19 subgenomic RNA was identified at position 2598 and an essential transcription signal for this mRNA mapped between positions 2534 and 2563. A mutant in which this essential promoter element has been deleted cannot transcribe the p19 subgenomic RNA and has lost infectivity in planta. These results indicate that the 3'-terminal region of the RT gene has a major function in cis for expression of p19, which is essential for infecting plants. A reason for retaining the RT C-terminal region in stable deletion mutants is still unknown.

Reassortment between genetically distinct Japanese and US strains of Soil-borne wheat mosaic virus: RNA1 from a Japanese strain and RNA2 from a US strain make a pseudorecombinant virus

Soil-borne wheat mosaic virus (SBWMV), the type species of the genus Furovirus, has a plus-sense bipartite RNA genome. Japanese and US strains of SBWMV are genetically distantly related, despite their biologically identical properties. Here we report formation of a pseudorecombinant virus consisting of RNA1 from a Japanese strain and RNA2 from a US strain, using infectious in vitro transcripts for both strains. Full-length infectious cDNA clones for a Japanese strain were previously constructed (Yamamiya and Shirako [38]). For RNA1 of a US strain, due to instability of full-length cDNA clones in Escherichia coli cells, it was necessary to prepare a full-length template DNA for in vitro transcription by combining overlapping 5'-terminal and 3'-terminal cDNAs individually cloned in two plasmids, whereas for RNA2 a full-length cDNA clone was the template. For infectivity assays, Chenopodium quinoa, a local lesion host, and wheat, a systemic host, were used. A mixture of Japanese RNA1 transcripts and US RNA2 transcripts caused formation of local lesions on C. quinoa leaves and systemic infection to wheat plants. The nucleotide sequence of the progeny viral RNA2 was identical to that of the US RNA2. The reciprocal combination was not infectious to either host. These results confirm that the Japanese and US SBWMV are genetically distantly related strains belonging to a single species.

Construction of full-length cDNA clones to Soil-borne wheat mosaic virus RNA1 and RNA2, from which infectious RNAs are transcribed In vitro: virion formation and systemic infection without expression of the N-terminal and C-terminal extensions to the capsid protein

The 19-kDa capsid protein (CP) of Soil-borne wheat mosaic furovirus (SBWMV) is encoded in the 5'-terminal region of RNA2. In addition to CP, two CP-related proteins are translated from SBWMV RNA2: (1) a 24-kDa protein (N-CP) with an N-terminal 40-amino-acid extension initiated at an upstream in-frame CUG codon; and (2) an 83-kDa protein (CP-RT) with an about 580-amino-acid, C-terminal extension by partial translational readthrough at the UGA termination codon at the end of the CP gene. We examined requirements for N-CP and CP-RT on virion formation and systemic infection in wheat plants using full-length cDNA clones, from which infectious RNA can be transcribed in vitro. RNA2 mutants, which could not synthesize N-CP, CP-RT, or either infected wheat plants systemically in combination with the wild-type RNA1 transcripts, produced rod-shaped virus particles in uninoculated upper leaves. Original mutations which abolished translation of N-CP and CP-RT were confirmed on RNA2 extracted from purified virus from the upper leaves by nucleotide sequence analysis. These results indicate that neither N-terminal nor C-terminal extensions to the CP are required for virion formation and systemic infection of SBWMV in wheat plants.