Michiaki Takii

Endoscopic and Histopathological Evaluation of Collagenous Colitis

Collagenous colitis (CC) is a well-known cause of chronic non-bloody diarrhea, especially in elderly women. CC is characterized histopathologically by an increase in the thickness of the subepithelial collagen layer to at least 10 µm, epithelial damage, and chronic inflammation of the lamina propria. Generally, the colonic mucosa in CC is macroscopically normal, although minor, non-specific abnormalities may be found. Due to the recent advancement of endoscopic and diagnostic technologies, however, microscopic mucosal abnormalities and specific longitudinal linear lacerations of the mucosa characteristic of CC have been identified. The association of CC with non-steroidal anti-inflammatory drugs and proton pump inhibitors has also been reported. Since definitive diagnosis of CC has to rely on pathologically documented collagen bands and mononuclear infiltration, the efficiency and precision of colonic biopsy need to be improved. Of the 29 CC patients that we have encountered at our institution, it was in 15 of 29 cases that the endoscopic finding that we performed a biopsy on was apparent. Our comparison of the endoscopic and histopathological findings of CC in the 15 patients showed that the mucosa frequently appeared coarse and nodular on the surface of the mucosa, which was also significantly thicker in collagen bands, demonstrating a strong correlation between collagen band formation and CC. Also, the coarse and nodular surface of the mucosa was most frequently seen affecting the proximal colon. The results suggest that endoscopic observation and biopsy of the proximal colon, where a coarse and nodular surface of the mucosa is often found, may be useful for confirmation of the diagnosis in patients with suspected CC.

Sonographic Visualization of Fecal Loading in Adults: Comparison With Computed Tomography

The aim of this study was to compare ultrasonographic assessment of fecal loading in adults with that of computed tomography. Ultrasonography (US) was performed on 43 adult patients immediately after abdominal computed tomography images had identified fecal loading in their colons. In 18 of 43 patients (haustrations-visualized cases), fecal loading was detected as crescent-shaped acoustic shadows associated with haustrations behind the strong echoes off the colon wall. In the remaining 25 patients (haustrations-not-visualized cases), fecal loading was detected as attenuating echoes with multiple high echoic spots behind weak high echoes off the colon wall in 17 patients and similar to those seen in the haustrations-visualized cases but without haustrations in 8 patients. US can be used for qualitative assessment of fecal loading in the colon. This new technique is simple and noninvasive and can be used concomitantly with physical examination to assess severity of constipation.

INTRADUCTAL ULTRASONOGRAPHY OF THE GALLBLADDER IN APPLICATION OF THE ENDOSCOPIC NASO-GALLBLADDER DRAINAGE

Background:  Although endoscopic naso‐gallbladder drainage (ENGBD) for gallbladder disease is useful, the procedure is difficult and investigations involving many cases are lacking. Furthermore, reports on transpapillary intraductal ultrasonography (IDUS) of the gallbladder using a miniature probe are rare.

Pancreatic Regeneration by Long-Term Oral Administration of a Protease Inhibitor in a Rat Model of Chronic Pancreatitis

Background/Aims: We previously reported early-stage pancreatic histological features in an experimental chronic pancreatitis model, prepared by injecting oleic acid into the pancreatic duct. In this model, on day 2 after injection, reactive fibroblasts in association with inflammation appeared in the stroma, however, myofibroblasts, which were activated fibroblasts, were not detected. On day 4, myofibroblasts appeared in the stroma, and the lobular architecture was destroyed. On day 28, pancreatic acinar cells were completely necrotized and exfoliated, and the stroma was replaced by collagen fibers. On the other hand, it is known that the long-term oral administration of a protease inhibitor (PI) to rats causes pancreatic enlargement as a trophic effect. In this study, we investigated the trophic effect of an oral PI on the rat pancreas. And we examined the trophic effect on pancreatic regeneration in a pancreatic fibrosis model. Subjects: Male Wistar rats weighing about 200 g were used. ONO-3403 (Ono Pharmaceutical Co., Ltd., Osaka, Japan) was used as a potent oral PI. The PI action of ONO-3403 is five-fold stronger than that of camostat mesilate, the only oral PI now used clinically in Japan. Methods: (1) Normal rats were fed with standard feed or 0.1% ONO-3403-containing feed. The pancreases were removed on day 7, 14, 25. Pancreatic amylase, protein, and DNA contents, as well as pancreatic wet weights, were measured. (2) The abdominal cavity of rats was opened, 100 μl of oleic acid, a cytotoxic agent, was injected into the pancreatic duct, and the cavity was closed. Administration of 0.1% ONO-3403-containing feed was started from day 2 (A gourp) or from day 4 (B group) after injection. On day 28, the pancreases were removed and examined. Results: (1) On day 25 after ONO-3403 administration, the pancreatic wet weights increased over time by about 2.2 times. The amylase, protein, and DNA contents increased by about 3.7, 2.9, and 1.8 times, respectively. The increased protein content suggestive of “hypertrophy” was more marked than the increased DNA content suggestive of “hyperplasia”. (2) In the A group on day 28, pancreatic histological features showed the inhibition of pancreatic fibrosis and regeneration of pancreatic acinar cells. In addition, the pancreatic wet weights and contents similarly increased. However, in the B group on day 28, no improvement of pancreatic fibrosis was found. Conclusions: (1) The long-term oral administration of a potent PI showed marked trophic effects on the rat pancreas, however, the trophic effects contributed to hypertrophy rather than hyperplasia. (2) In a pancreatic fibrosis model, the long-term oral administration of a potent PI, from an early stage when no myofibroblasts appeared in the pancreatic stoma, also showed pancreatic trophic effects and led to the regeneration of pancreatic acinar cells.

THE ROLE OF LINEAR ARRAY EUS FOR DIAGNOSIS OF PANCREATIC MALIGNANCIES IN THE CURRENT SITUATION

Over the last few decades, the role of endoscopic ultrasound (EUS) in the diagnosis of pancreatic malignancies has greatly increased by allowing earlier diagnosis and appropriate staging. The development of linear array EUS also allows fine needle aspiration (FNA) to be carried out under real‐time EUS guidance and offers definitive diagnosis, which has fundamentally changed the diagnostic approach to pancreatic malignancies. Moreover, linear array EUS with the EUS‐FNA technique has a therapeutic application that has expanded the role of this procedure in the management of pancreatic malignancies. This review will focus on the features of linear array EUS and discuss the current role of linear array EUS in the diagnosis of pancreatic malignancies.

S1330 A New Noninvasive Method of Assessing Pancreatic Exocrine Function By a Breath Test in Patients with Chronic Pancreatitis

Background: “Bulls eye calculi” and a preserved pancreatic parenchyma have been founded in patients suffering from chronic pancreatitis associated with gene mutation (CPgm+). Aim: To evaluate radiological pancreatic findings in patients suffering from chronic calcifying pancreatitis. Patients and methods: From May 2006 to June 2007, 27 patients suffering from chronic calcifying pancreatitis were prospectively enrolled. Exclusion criteria were: patients with previous pancreatic surgery. All patients were underwent genetic tests (35 main CFTR gene mutations, R121H and N29I gene mutations on PRSS1 gene, and N34S gene mutation on SPINK1 gene) and MDCT. Images analysis was evaluated by two independent radiologists. Qualitative criteria were: structure of the endoductal calculi (homogeneous/ heterogeneous with presence of a non-calcified central core “bulls eye”), pancreatic parenchyma contrast-enhancement in pancreatic phase compared to renal cortex (hypo-/iso-/ hyper-vascular). Quantitative criteria were: number and diameter of endoductal calculi, size of pancreatic parenchyma (head, body, tail), size of main pancreatic duct (MPD). Results: 27 patients (17 males and 10 females mean age 45 ± 12 yrs) were enrolled in the study. We found 8 gene mutations in seven pts (26%) (4 CFTR, 3 SPINK1 and 1 PRSS1). Heterogeneous calculi with non-calcified central core (“bulls eye”) were observed in 7 out of 27 pts (25%), 5 out of 7 in CPgm+ group (71%) and 2 out of 20 (10%) in CPgmgroup (p= 0.005). The 2 CPgmpatients with presence of “bulls eyes” calculi at MDCT had clinical characteristic suggestive for the presence of gene mutations (age at onset 20 and 25 yrs). The other radiological qualitative and quantitative analysis is reported in Table. Conclusions: The presence of “bulls eye” calculi at MDCT are suggestive for chronic pancreatitis associated with gene mutations.

NASOGALLBLADDER DRAINAGE FOR MIRIZZI’S SYNDROME

The authors experienced a case of Mirizzi’s syndrome successfully treated with endoscopic nasogallbladder drainage (ENGBD). The patient was a 63‐year‐old man. He was admitted with abdominal pain and jaundice. Laboratory data indicated leukocytosis and elevation of serum bilirubin level. Abdominal ultrasound showed marked swelling of gallbladder and debris in the gallbladder, therefore, the authors strongly suspected Mirizzi’s syndrome. He had past history of acute myocardial infarction and treated with anticoagulation therapy. Then, the authors couldn’t perform surgical removal or percutaneous transhepatic drainage, and tried endoscopic transpapillary drainage. Endoscopic retrograde cholangiopancreatography revealed smooth stricture in the superior portion of common bile duct and occlusion of the cystic duct, and ENGBD was then performed. After ENGBD, his complaints, laboratory data, swelling of gallbladder and stricture of common bile duct were all remarkably improved.