Etiology of recurrent acute pancreatitis, with special emphasis on pancreaticobiliary malformation.

PURPOSE: This study was aimed to investigate etiology and clinical profiles of recurrent acute pancreatitis (RAP), particularly from the morphology of the pancreaticobiliary duct system. MATERIAL AND METHODS: Pancreaticobiliary morphology was examined in 230 of 381 patients with acute pancreatitis (AP) using endoscopic retrograde cholangiopancreatography. We analyzed factors associated with RAP including the pancreaticobiliary duct system. RESULTS: RAP was diagnosed in 74 patients (19%). Major etiologies of RAP were alcoholic (38%), idiopathic (26%) and pancreaticobiliary malformation (22%). Patients with alcoholic RAP were significantly younger (47.2±11.6 years) than those with gallstone RAP (67.3±16.8; p<0.05). RAP with pancreaticobiliary malformation (male-to-female ratio: 1:4.3; p<0.01) and gallstone RAP (1:1.7; p<0.05) occurred predominantly in females in comparison with alcoholic RAP (1:0.2). Recurrence rate was 80% for AP with pancreaticobiliary malformation, significantly higher than for the others (p<0.01). Pancreas divisum was suspected as the etiology of mild RAP in 7 patients. Four RAP patients with pancreas divisum underwent endoscopic minor papilla sphincterotomy and improved. Pancreaticobiliary maljunction with biliary dilatation (choledochal cyst) was suspected as the etiology of mild RAP in 3 patients. The 3 RAP patients with choledochal cyst underwent prophylactic flow diversion surgery with complete resection of the dilated common bile duct, and achieved improvement. High confluence of pancreaticobiliary ducts was suspected as the etiology of mild RAP in 6 patients. CONCLUSION: Pancreaticobiliary malformation is one of the major causes of RAP. As some of them benefit from endoscopic or surgical treatment, morphology of the pancreaticobiliary duct system should be examined where possible in RAP patients.

Standard steroid treatment for autoimmune pancreatitis.

OBJECTIVE: To establish an appropriate steroid treatment regimen for autoimmune pancreatitis (AIP). METHODS: A retrospective survey of AIP treatment was conducted in 17 centres in Japan. The main outcome measures were rate of remission and relapse. RESULTS: Of 563 patients with AIP, 459 (82%) received steroid treatment. The remission rate of steroid-treated AIP was 98%, which was significantly higher than that of patients without steroid treatment (74%, 77/104; p<0.001). Steroid treatment was given for obstructive jaundice (60%), abdominal pain (11%), associated extrapancreatic lesions except the biliary duct (11%), and diffuse enlargement of the pancreas (10%). There was no relationship between the period necessary to achieve remission and the initial dose (30 mg/day vs 40 mg/day) of prednisolone. Maintenance steroid treatment was given in 377 (82%) of 459 steroid-treated patients, and steroid treatment was stopped in 104 patients. The relapse rate of patients with AIP on maintenance treatment was 23% (63/273), which was significantly lower than that of patients who stopped maintenance treatment (34%, 35/104; p = 0.048). From the start of steroid treatment, 56% (55/99) relapsed within 1 year and 92% (91/99) relapsed within 3 years. Of the 89 relapsed patients, 83 (93%) received steroid re-treatment, and steroid re-treatment was effective in 97% of them. CONCLUSIONS: The major indication for steroid treatment in AIP is the presence of symptoms. An initial prednisolone dose of 0.6 mg/kg/day, is recommend, which is then reduced to a maintenance dose over a period of 3-6 months. Maintenance treatment with low-dose steroid reduces but dose not eliminate relapses.

Can MRCP replace ERCP for the diagnosis of autoimmune pancreatitis?

BACKGROUND: It is of utmost importance that autoimmune pancreatitis (AIP) be differentiated from pancreatic cancer. Irregular narrowing of the main pancreatic duct is a characteristic finding in AIP; it is useful for differentiating AIP from pancreatic cancer stenosis. This study evaluated the usefulness of magnetic resonance cholangiopancreatography (MRCP) for the diagnosis of AIP and assessed whether MRCP could replace endoscopic retrograde cholangiopancreatography (ERCP) for diagnosing AIP. METHODS: The MRCP and ERCP findings of 20 AIP patients were compared. RESULTS: On MRCP, the narrowed portion of the main pancreatic duct was not visualized, while the noninvolved segments of the pancreatic duct were visualized. The degree of upstream dilatation of the proximal main pancreatic duct was milder in AIP than in pancreatic cancer patients. In the skipped type, only skipped narrowed lesions were not visualized. After steroid therapy for AIP, the nonvisualized main pancreatic duct became visualized. CONCLUSIONS: MRCP cannot replace ERCP for the diagnosis of AIP, since narrowing of the main pancreatic duct in AIP was not visualized on MRCP. MRCP findings of segmental or skipped nonvisualized main pancreatic duct accompanied by a less dilated upstream main pancreatic duct may suggest the presence of AIP. MRCP is useful for following AIP patients.

Therapeutic strategy for autoimmune pancreatitis.

Autoimmune pancreatitis (AIP) is a particular type of pancreatitis that is thought to have an autoimmune etiology. Before therapy for AIP is begun, accurate diagnosis of AIP is necessary. It is important to distinguish AIP from pancreatic cancer. Since there is currently no diagnostic serological marker for AIP, AIP should be diagnosed on the basis of a combination of abnormalities unique to AIP. The Japanese "Diagnostic Criteria for Autoimmune Pancreatitis 2006" require the characteristic imaging findings of AIP and that at least one of the laboratory criteria or histopathological criteria have to be present. Unlike in patients with usual chronic pancreatitis, corticosteroid therapy is frequently effective in resolving the morphological findings and the symptoms of AIP patients. Therefore, administration of oral steroid therapy has become standard therapy for AIP. Indications for steroid therapy for AIP are thought to include obstructive jaundice due to stenosis of the bile duct, associated extrapancreatic sclerosing lesions, and diabetes mellitus coincidental with AIP. Oral prednisolone is usually started at 30 mg/day and tapered by 5 mg every 1-2 weeks. Serological and imaging tests are followed periodically after commencement of steroid therapy. Patients in whom complete radiological improvement is documented can stop their medication. To prevent relapses, continued maintenance therapy with prednisolone 2.5-5 mg/day is sometimes required. Patients who relapse should be re-treated with high-dose steroid therapy. A poor response to steroid therapy should raise the possibility of pancreatic cancer and the need for further examination, including laparotomy.

Pancreatographic investigation of the pancreatic duct system.

BACKGROUND: Embryologically, the pancreatic duct system develops by the fusion between the dorsal and ventral pancreatic bud ducts. It has been suggested that the proximal part of the main dorsal pancreatic duct partially regresses to form the accessory pancreatic duct (APD). Aim of this study was to clarify the anatomy of the pancreatic duct system of the head of the pancreas and investigate the embryology of the normal pancreatic duct system. METHODS: We reviewed endoscopic retrograde pancreatography of normal pancreatic heads (n = 256) and pancreas divisum (n = 36), focusing on long inferior branches arising from the APD and the main pancreatic duct (MPD). The accessory pancreatograms were divided into two patterns of course and shape, the long type (171 cases) and the short type (85 cases) according to the length of the MPD from the orifice to the junction with the APD. The long-type APD formed a straight line and joined the MPD at the neck portion of the pancreas. The short-type APD joined the MPD near its first inferior branch. RESULTS: The shape of the long-type APD was quite similar to that of the dorsal pancreatic duct of pancreas divisum. The short-type APD was less likely to have a long inferior branch arising from the APD. The length of the APD from the orifice to the first long inferior branch was similar in the long-type APD (19.4 +/- 4.0 mm) and in the short-type APD (18.8 +/- 4.2 mm). The first long inferior branch from the long-type APD passed though the MPD near the origin of the inferior branch from the MPD, whereas the short-type APD joined the MPD near its inferior branch. CONCLUSIONS: There are two types of APD. The long-type APD was quite similar to the shape of the dorsal pancreatic duct of pancreas divisum, and seems to represent a continuation of the main duct of the dorsal pancreatic bud. The short-type APD was less likely to have a long inferior branch, and seems to be formed by the most proximal part of the main duct of the dorsal pancreatic bud and its long inferior branch.

MRCP of congenital pancreaticobiliary malformation.

BACKGROUND: Congenital pancreaticobiliary malformations are sometimes associated with acute or chronic pancreatitis and biliary carcinoma. Currently, magnetic resonance cholangiopancreatography (MRCP) is one of the first choices for investigating and diagnosing pancreaticobiliary diseases noninvasively. We compared the accuracy of conventional MRCP and endoscopic retrograde cholangiopancreatography (ERCP) in making the diagnosis of congenital pancreaticobiliary malformations. METHODS: In patients with pancreas divisum (n = 17), pancreaticobiliary maljunction (n = 12), choledochocele (n = 2), and annular pancreas (n = 1) who underwent ERCP and MRCP, the diagnostic accuracy and findings on MRCP were compared with those on ERCP. RESULTS: Of the 32 patients with congenital pancreaticobiliary malformations diagnosed on ERCP, 23 (72%) presented the same diagnosis on MRCP. Complete pancreas divisum was diagnosed in 73% on MRCP based on the finding of a dominant dorsal pancreatic duct crossing the lower bile duct and emptying into the duodenum without communicating with the ventral pancreatic duct. Pancreaticobiliary maljunction was diagnosed in 75% on MRCP based on the finding of an anomalous union between the common bile duct and the pancreatic duct and the existence of a long common channel. CONCLUSIONS: Conventional MRCP is a useful, noninvasive tool for diagnosing congenital pancreaticobiliary malformations; and the diagnostic accuracy can be increased with three-dimensional MRCP or dynamic MRCP with secretin stimulation.

The presence of a common channel and associated pancreaticobiliary diseases: a prospective ERCP study.

BACKGROUND: There are few endoscopic retrograde cholangiographic studies dealing with the relationship between the presence of a common channel and associated pancreaticobiliary diseases. AIMS: To endoscopically determine the incidence of common channels and assess whether the anatomy of the pancreaticobiliary ductal drainage into the duodenum has any bearing on pancreaticobiliary diseases. PATIENTS AND METHODS: We prospectively examined a common channel formation in 354 endoscopic retrograde cholangiographic cases. Cases with a common channel were divided into three groups: pancreaticobiliary maljunction, high confluence of pancreaticobiliary ducts with a common channel > or =6 mm in which the communication was occluded with the sphincter contraction, and common channel < or =5 mm in length. RESULTS: A common channel was observed in 131 cases (37.0%) including 11 with pancreaticobiliary maljunction and 13 with high confluence of pancreaticobiliary ducts. In cases with a common channel, the incidences of associated gallbladder carcinoma and acute pancreatitis were both 11.5%, which were significantly higher than 1.8% and 4.9% seen in cases without a common channel. In pancreaticobiliary maljunction cases, incidence of associated gallbladder carcinoma was 72.7%. CONCLUSION: The presence of an obvious common channel was observed in 37.0%. A close relationship is suggested between the presence of a common channel and development of gallbladder carcinoma and acute pancreatitis.

Clinical management of autoimmune pancreatitis.

Autoimmune pancreatitis (AIP) is a newly described entity with characteristic clinical, radiological, serological, and histological features, in which autoimmune mechanisms seem to be involved in pathogenesis. Many new clinical aspects of AIP have been clarified during 10 years, and AIP has become a distinct entity recognized worldwide. However, precise pathogenesis or pathophysiology remains unclear. As AIP responds dramatically to steroid therapy, accurate diagnosis of AIP is necessary to avoid unnecessary laparotomy or pancreatic resection. It is importance to misdiagnose pancreatic cancer as AIP as well as to misdiagnose AIP as pancreatic cancer. In the absence of a diagnostic serological marker for AIP, its diagnosis rests on identifying unique patterns of abnormalities. Japanese criteria are based on the minimum consensus features of AIP and aim to avoid misdiagnosis of malignancy. It contain 3 items: (1) enlargement of the pancreas and narrowing of the main pancreatic duct; (2) high serum gammaglobulin, IgG, or IgG4, or the presence of autoantibodies; (3) histological findings of lymphoplasmacytic infiltration and fibrosis in the pancreas. For diagnosing AIP, the presence of the imaging criterion is essential. Other clinical characteristics of AIP are elderly male preponderance, fluctuating obstructive jaundice without pain, occasional association with diabetes mellitus and extrapancreatic lesions, and favorite responsiveness to oral steroid therapy. Elevation of serum IgG4 levels and infiltration of abundant IgG4-positive plasma cells in various organs are rather specific in AIP patients. In an elderly male presenting obstructive jaundice and pancreatic mass, AIP should be considered as one of differential diagnoses.

Close correlation between chronic sclerosing sialadenitis and immunoglobulin G4.

In four patients with chronic sclerosing sialadenitis, serum immunoglobulin G4 concentration was markedly increased and abundant infiltration of immunoglobulin G4-positive plasma cells was observed in the salivary glands. Autoimmune pancreatitis occurred in the two patients during follow up. Chronic sclerosing sialadenitis and autoimmune pancreatitis would appear to show essentially the same pathophysiological mechanism. Measurement of serum immunoglobulin G4 concentration is useful in differentiating chronic sclerosing sialadenitis from neoplasia.

IgG4-related sclerosing disease incorporating sclerosing pancreatitis, cholangitis, sialadenitis and retroperitoneal fibrosis with lymphadenopathy.

BACKGROUND AND AIMS: Autoimmune pancreatitis is usually associated with elevated serum IgG4 concentrations, and sometimes with sclerosing cholangitis and Sjögren's syndrome. This study aimed to elucidate the proposed entity of IgG4-related sclerosing disease. METHODS: Subjects were patients with autoimmune pancreatitis (n = 26), sclerosing sialadenitis (n = 5), chronic alcoholic pancreatitis (n = 20), sialolithiasis (n = 34), Sjögren's syndrome (n = 50), and primary sclerosing cholangitis (n = 3). Sections of various organs and tissues of these patients were examined immunohistochemically using antibodies to CD4-T, CD8-T, and CD20-B cell subsets and IgG4, and serum IgG4 concentrations were measured. RESULTS: Patients with autoimmune pancreatitis were associated with sclerosing cholangitis (n = 23), sclerosing sialadenitis (n = 2), retroperitoneal fibrosis (n = 2), and abdominal (n = 5) and cervical (n = 4) lymphadenopathy. They demonstrated infiltrations of more abundant IgG4-positive plasma cells in the pancreas, peripancreatic retroperitoneal tissues, extrahepatic bile duct, gallbladder, stomach, minor salivary gland, and abdominal lymph nodes compared with those of other diseases (p < 0.01). Such infiltrations were also observed in the minor salivary gland and submandibular gland of patients with sclerosing sialadenitis (p < 0.01). Serum IgG4 concentrations were significantly elevated in patients with autoimmune pancreatitis and sclerosing sialadenitis (p < 0.01). CONCLUSION: We propose a new clinicopathological entity of IgG4-related sclerosing disease incorporating sclerosing pancreatitis, cholangitis, sialadenitis and retroperitoneal fibrosis with lymphadenopathy.

Gastrointestinal findings in patients with autoimmune pancreatitis.

BACKGROUND AND STUDY AIMS: Autoimmune pancreatitis (AIP) is a condition that has been proposed as a clinical entity only fairly recently. Its pathogenesis involves autoimmune mechanisms. Although the radiological findings in patients with AIP have been well evaluated, few studies have focused on the gastrointestinal findings in these patients. The aim of this study was to explore the endoscopic and histological findings in the gastrointestinal tract in patients with autoimmune pancreatitis. PATIENTS AND METHODS: The endoscopic findings in the stomach (n = 10), the duodenum (n = 18), the major duodenal papilla (n = 18), and the colon (n = 5) in 24 patients with AIP were reviewed. These were compared with the results of histological examination of gastric mucosa (n = 13), duodenal mucosa (n = 9), the major duodenal papilla (n = 3), and colonic mucosa (n = 3) in these patients. All these specimens were subjected to immunohistochemical study using anti-IgG4 antibody. RESULTS: Foci of slightly pale, thickened mucosa with loss of visible vascular pattern were observed in the stomach in four patients and in the colon in two patients on endoscopy. Slight or moderate swelling of the major duodenal papilla was detected in five patients. Slight to moderate lymphoplasmacytic infiltration was observed in the lamina propria of the gastric and colonic mucosa, and of the major duodenal papilla. Heavy infiltration with IgG4-positive plasma cells (>10 cells per high-power field) was observed in the lamina propria of the stomach in seven patients, of the colon in two patients, and of the major duodenal papilla in three patients; this was not observed in the control patients, who had other diseases. CONCLUSIONS: Although there were no specific endoscopic findings in the stomach or colon in patients with autoimmune pancreatitis, foci of slightly pale, thickened mucosa with loss of visible vascular pattern were observed in some cases. This indistinct change seen on endoscopy appears to be due to heavy infiltration with IgG4-positive plasma cells, associated with CD4- or CD8-positive T lymphocytes, in the lamina propria of the gastric or colonic mucosa.

Origin of the long common channel based on pancreatographic findings in pancreaticobiliary maljunction.

BACKGROUND AND AIMS: The origin of a long common channel in pancreaticobiliary maljunction was suggested to be the ventral pancreatic duct. Pathogenesis of long common channels was investigated by anatomically analysing the arrangement of pancreatic ducts in pancreaticobiliary maljunction. MATERIALS AND METHODS: Cholangiopancreatography was performed for 66 cases of pancreaticobiliary maljunction and 200 controls. The accessory pancreatic duct was classified according to course and shape. In cases with long- or short-type accessory pancreatic duct, lengths of the main pancreatic duct from orifice to first inferior branch and junction with the accessory pancreatic duct, and the common channel were measured. RESULTS: Lengths of the main pancreatic duct from orifice to first inferior branch or junction with the accessory pancreatic duct were significantly longer in cases of pancreaticobiliary maljunction cases with the long- or short-type accessory pancreatic duct than in controls (p<0.01). Lengths of the main pancreatic duct from first inferior branch to junction with the accessory pancreatic duct were roughly equivalent in pancreaticobiliary maljunction and controls. CONCLUSIONS: Long common channels in pancreaticobiliary maljunction might be formed embryologically with adhesion of the right ventral pancreatic duct and the terminal portion of the bile duct.

Morphological changes after steroid therapy in autoimmune pancreatitis.

BACKGROUND: Although many patients with autoimmune pancreatitis undergo steroid therapy, detailed evaluation of morphological changes in the pancreas and bile duct following therapy has not been performed in this disease. In this study serological and morphological changes occurring during steroid treatment of autoimmune pancreatitis are comparatively examined. METHODS: Ten patients with autoimmune pancreatitis were treated with corticosteroids. Morphological findings were: pancreatic enlargement (n = 9), irregular narrowing of the main pancreatic duct (n = 10), and biliary stenosis (n = 9). An initial dose of prednisolone was 40-30 mg/day, and this was tapered by 5 mg every 1-2 weeks. All patients underwent ultrasound and serological testing 1-2 weeks after commencing medication, followed by weekly serological testing and by CT and endoscopic retrograde cholangiopancreatography after 1-2 months. Radiological and serological changes were compared. RESULTS: All 10 patients were responsive to steroid therapy. Pancreatic size normalized within 1 month; however, irregularity of the pancreatic duct remained in 6 patients. Rigidity or lateral deformity of the bile duct remained in 3 patients and biliary stenosis persisted in 5. Four patients in whom elevated serum IgG4 failed to normalize also showed incomplete morphological improvement. Three patients with complete improvement of the pancreatic duct stopped medication, but recurrence of pancreatitis did not occur. CONCLUSIONS: Although steroid therapy was morphologically and serologically effective in patients with autoimmune pancreatitis, cholangiopancreatographic abnormalities remained in many patients. Morphological improvement on cholangiopancreatography and normalization of serum IgG4 after steroid therapy appeared to be good indicators for discontinuing medication in patients with autoimmune pancreatitis.

Close relationship between autoimmune pancreatitis and multifocal fibrosclerosis.

BACKGROUND: Autoimmune pancreatitis is a unique clinical entity proposed recently, and is sometimes associated with inflammation of other organs. AIMS: To examine the pathophysiology of the pancreas and other organs in patients with autoimmune pancreatitis. PATIENTS AND METHODS: We evaluated clinicopathological findings in six resected and one autopsied patient with autoimmune pancreatitis. The pancreas, peripancreatic tissue, bile duct, and gall bladder were examined histologically and immunohistochemically. Biopsied salivary gland and cervical lymph node of one patient were also examined. We also performed similar immunohistochemical examinations in pancreatectomy specimens from 10 patients with alcoholic chronic pancreatitis and biopsied salivary glands from five patients with Sjögren's syndrome. RESULTS: Stenosis of the extrahepatic bile duct was detected in all patients. Histological findings were characterised by diffuse lymphoplasmacytic infiltration with marked interstitial fibrosis and acinar atrophy, obliterated phlebitis of the pancreatic veins, and involvement of the portal vein. Immunohistochemically, diffusely infiltrating cells consisted predominantly of CD4 or CD8 positive T lymphocytes and IgG4 positive plasma cells. Similar inflammatory processes also involved the peripancreatic tissue, extrahepatic bile duct, gall bladder, and salivary gland. Lymph nodes were swollen with infiltration of IgG4 positive plasma cells. None of these findings was seen in alcoholic chronic pancreatitis or Sjögren's syndrome. CONCLUSIONS: The development of the specific inflammations in extensive organs as well as the pancreas in patients with autoimmune pancreatitis strongly suggests a close relationship between autoimmune pancreatitis and multifocal fibrosclerosis.

Survival benefits of adjuvant chemotherapy with oral doxifluridine (5'-DFUR) following radiotherapy in patients with unresectable pancreatic cancer.

BACKGROUND AND OBJECTIVES: The combination of 5-fluorouracil and radiotherapy is thought to be the most effective treatment for locally unresectable pancreatic carcinoma. The outcomes, however, are far from acceptable from the viewpoint of long-term survival. We assessed the survival benefits of oral adjuvant chemotherapy with doxifluridine (5'-DFUR) following radiotherapy for patients with the disease. METHODS: Thirty-five consecutive patients who underwent bypass surgery and radiotherapy for localized advanced unresectable adenocarcinoma of the pancreas head were retrospectively reviewed in regard to disease progression and survival. Ten of the 35 patients underwent adjuvant chemotherapy with 5'-DFUR after radiotherapy in an outpatient setting. RESULTS: The 1-year survival for patients treated with radiotherapy alone was 29%. The 1-, 2-, and 3-year survivals for patients treated with the adjuvant chemotherapy after radiotherapy were 50, 40, and 30%, respectively (P = 0.0069, log-rank test). The elevation of tumor markers was delayed (P = 0.0346) and local control rate was improved (P = 0.0475) in patients with chemotherapy. Multivariate analysis demonstrated that the adjuvant chemotherapy with 5'-DFUR was a significant independent prognostic factor as well as tumor size. CONCLUSIONS: The adjuvant chemotherapy with 5'-DFUR following radiotherapy led to a significant prolongation of the survival for patients with unresectable localized pancreatic cancer.

Winter seasonality and rotavirus diarrhoea in adults.

We investigated the aetiological role of group A rotavirus in adults with acute diarrhoea in a 4-year prospective study. Of 683 patients with acute diarrhoea, 97 (14%) shed rotavirus as a sole agent, whereas six (5%) of 115 patients without diarrhoea shed rotavirus. Half of patients with rotavirus diarrhoea required admission to hospital. Unlike rotavirus diarrhoea in children, the occurrence of rotavirus-positive cases did not show a significant winter seasonality. Rotavirus infection should be included in the differential diagnosis of diarrhoeal diseases in adults.

A new embryologic hypothesis of annular pancreas.

Annular pancreas is a developmental anomaly of the pancreas. There are two major hypotheses concerning development of the annular pancreas from the ventral pancreatic anlage; adhesion of the right ventral anlage to the duodenal wall (Lecco's theory), and persistence of the left ventral anlage (Baldwin's theory) reported in 1910, but each theory has some problems and can account for only a few types of annular pancreas. We report a new embryologic hypothesis of annular pancreas which can account for the developmental mechanism of three types of arrangement of annular ducts. The tip of the left ventral anlage adheres to the duodenum and stretches to form a ring. Whether the tip is proximal or distal to the bile duct creates several arrangements of the annular duct.