自身免疫性胰腺炎误诊误治17例临床分析

目的 总结自身免疫性胰腺炎(AIP)误诊误治的原因.方法 回顾性分析2005年5月至2010年7月间我院收治的17例有误诊误治经历的AIP患者的临床资料.结果 AIP的主要临床症状包括腹部轻度疼痛13例、进行性黄疸12例、发热6例、体重减轻9例.15例伴随一种或一种以上胰腺外脏器的自身免疫性疾病,包括过敏性鼻炎、颌下淋巴结肿大、颌下腺肿大、过敏性哮喘、类风湿性关节炎、干燥综合征、糖尿病、原发性硬化性胆管炎和自身免疫性肝炎.实验室检查方面,血清球蛋白增高11例、IgG增高14例、γ球蛋白增高13例、抗核抗体阳性13例、抗胰岛素IgG抗体阳性2例.影像学检查方面,胰腺弥漫性肿大15例,伴主胰管弥漫性狭窄或节段性狭窄、胰腺段胆总管狭窄、近端胆管扩张、胆囊增大;胰头、钩突局灶性肿大2例.17例中有13例误诊为胰腺癌,其中4例行胰十二指肠切除术,7例行胆肠吻合术,2例被认为肿瘤晚期失去治疗机会;4例被误诊为普通慢性胰腺炎.确诊AIP后,17例患者均接受糖皮质激素治疗,效果显著.随访6～45个月(平均15个月),4例复发,再次子糖皮质激素治疗效果好.随访期间未发现胰腺癌.结论 AIP 临床特点与胰腺癌相似,加之我国现阶段对AIP认识不足、重视不够,是导致误诊和误治的主要原因.

Abstract：

Objective To summarize the reasons of mis-diagnosis and mis-treatment of autoimmune pancreatitis (AIP). Methods Clinical data of 17 patients with AIP,who were admitted to the hospital from May 2005 to July 2010 and experienced mis-diagnosis and mis-treatment, were retrospectively analyzed. Results The main clinical manifestations included epigastric pain (13 cases),progressive obstructive jaundice (12 cases), fever (6 cases) and weight loss (9 cases). Fifteen patients had extrapancreatic organ involvemnet, including allergic rhinitis, swelling of lymphoglandulae submaxillares, swelling of submaxillary gland, allergic asthma, rheumatoid arthritis, Sjogren syndrome, diabetes mellitus, primary sclerosing cholangitis and autoimmune hepatitis. Of these 17 cases, 11 cases presented with high serum globulin, 14 cases with high serum IgG, 13 cases with high serum γ-globulin, 13 cases with positive anti-nuclear antibody and 2 cases with positive anti-insulin IgG antibody. The abdominal imaging demonstrated that 15 patients had diffuse enlargement of the pancreas with diffuse or segmental narrowing of main pancreatic duct, narrowing of the intrapancreatic common bile duct, dilation of the proximal biliary duct and gallbladder enlargement. Focal enlargement of the pancreas was found in 2 cases. Thirteen cases were misdiagnosed as pancreatic carcinoma. Among them, 4 cases underwent pancreaticoduodenectomy and 7 cases underwent choledochojejunostomy. Two cases were misdiagnosed as end stage of cancer that lost therapeutic chance. Another 4 cases were misdiagnosed as chronic pancreatitis. Steroid therapy was administered in all patients with satisfactory response. All patients were followed-up for 15 months (ranged from 6 months to 45 months), and recurrence was found in 4 cases. Satisfactory response was found in patients treated with steroid for the second time. No pancreatic cancer was found in these patients in the follow up period. Conclusion The main causes of mis-diagnosis and mis-treatment of AIP may be contributed by difficulty in differentiating AIP from pancreatic carcinoma based on clinical manifestations and inadequate knowledge of AIP as well as insufficient attention to AIP in China.     

Clinical difficulties in the differentiation of autoimmune pancreatitis and pancreatic carcinoma

OBJECTIVES: Autoimmune pancreatitis (AIP) is a newly described entity with characteristic clinical, histologic, and morphologic changes, in which autoimmune mechanisms are involved in pathogenesis. However, difficulties can arise in the differentiation of AIP from pancreatic carcinoma. The aims of this study were to clarify clinical and radiologic features of AIP to elucidate areas of diagnostic confusion. METHODS: Clinical, serologic, and radiologic findings were evaluated in 17 patients with AIP. RESULTS: All 17 patients were initially suspected to have pancreatic carcinoma. The patients were predominantly elderly men who frequently presented with jaundice but without features of acute pancreatitis. Elevation of serum gamma-globulin and IgG along with the presence of autoantibodies were usually evident, whereas serum tumor markers were elevated in 54% of cases. Stenosis of the bile duct was detected in 94% of cases. Diffuse enlargement of the pancreas and irregular narrowing of the main pancreatic duct were radiologically characteristic; however, segmental swelling and narrowing were detected in seven and two patients, respectively. In segmental cases, neither atrophy of the distal pancreas nor marked upstream dilation of the distal main pancreatic duct was observed.Angiographic abnormalities occurred in 54% of cases. Serologic and radiologic abnormalities showed considerable improvement with steroid therapy. CONCLUSIONS: Frequent stenosis of the bile duct, elevation of serum tumor markers, segmental pancreatic enlargement or narrowing of the main pancreatic duct, and angiographic abnormalities can cause confusion in the differential diagnosis of AIP and pancreatic carcinoma.     

中老年人自身免疫性胰腺炎的磁共振表现

目的 探讨中老年人自身免疫性胰腺炎(AIP)的磁共振(MRI)特征. 方法 17例经组织学或类固醇激素治疗证实的中老年AIP患者,均接受MRI检查,对患者的临床和MRI资料进行回顾性分析. 结果 17例中老年AIP中,13例AIP表现为胰腺弥漫性肿大,4例为局限性肿大或局限性信号异常.病变T_1WI上呈明显低信号,在T_2WI上呈轻度高信号,动脉期强化减弱但呈现明显的延时强化.13例在胰腺病变周围环绕包膜样结构.15例AIP伴有胰腺段胆总管的狭窄,5例胰胆管磁共振显示胰管不规则狭窄.11例AIP的平均表观扩散系数值为1.64×10~3mm~2/s. 结论 AIP好发于中老年人;其MRI特征包括胰腺呈香肠样或香蕉样肿大、病变胰腺周围延迟强化的包膜样影、胰管弥漫不规则狭窄等,MRI既可用于诊断AIP,也是评价其疗效的重要手段.     

MRCP and MRI findings in 9 patients with autoimmune pancreatitis

AIM: To evaluate magnetic resonance cholangiopancre-atography (MRCP) findings in conjunction with magnetic resonance (MR) images in autoimmune pancreatitis (AIP) patients. METHODS: Nine patients with AIP underwent MRI, MRCP, endoscopic retrograde cholangiopancreatography (ERCP), computed tomography, and ultrasonography. The MRCP and MR images taken before and after steroid therapy were reviewed and compared with other imaging modalities. The MRCP findings of the AIP cases were compared to those of 10 cases with carcinoma of the head of the pancreas. RESULTS: On MRCP, the narrowed portion of the main pancreatic duct noted on ERCP was not visualized, while the non-involved segments of the main pancreatic duct were visualized. The degree of upstream dilatation of the proximal main pancreatic duct was milder than that seen in cases of pancreatic carcinoma. Stenosis or obstruction of the lower bile duct was detected in 8 patients. MR images showed enlargement of the pancreas with decreased signal intensity on T1-weighted MR images, increased signal intensity on T2-weighted MR images, and, in 3 patients, a hypointense capsule-like rim. After steroid therapy, the previously not visualized portion of the main pancreatic duct was seen, along with improvement of the bile duct stenosis. Pancreatic enlargement decreased, and the abnormal signal intensity on both T1- and T2-weighted MR images became isointense. CONCLUSION: MRCP cannot differentiate irregular narrowing of the main pancreatic duct seen with AIP from stenosis of the main pancreatic duct seen with pancreatic carcinoma. However, MRCP findings in conjunction with MR imaging of pancreatic enlargement that shows abnormal signal intensity on T1- and T2-weighted MR images are useful in supporting a diagnosis of AIP.     

自身免疫性胰腺炎的影像特征及其诊断价值

目的 探讨自身免疫性胰腺炎(AIP)的影像特征及其在AIP诊断中的价值.方法 回顾性分析13例AIP患者的影像和临床资料.结果 11例AIP表现为胰腺弥漫性肿大,2例胰头局限性肿大.CT平扫病变密度均均匀.4例在MR T1WI上信号降低、T2WI上信号轻度升高,增强后动脉期病变轻度强化,门脉期及延迟期进一步强化.9例胰腺周围有包膜样结构.横轴位图像上肝内外胆管扩张、胆总管胰腺段狭窄或闭塞10例,胰管未显影11例.6例行MRCP者有4例显示胆总管胰腺段较大范围狭窄或闭塞,胰管节段性狭窄.7例ERCP显示胰管弥漫性、不规则狭窄.胰周静脉受累8例,肾脏多发低密度灶6例,腹膜后纤维化2例,肝门部胆管狭窄1例,肺间质病变1例,强直性脊柱炎1例.结论 AIP的影像学征象具有一定特征性,影像检查在AIP诊断中起重要作用.识别胰腺外脏器受累对正确诊断AIP有帮助.     

Autoimmune pancreatitis associated with a large pancreatic pseudocyst that disappeared after corticosteroid therapy: a case report and literature review

A 51-year-old woman was admitted to our department because of upper abdominal pain. The serum IgG4 concentration was elevated, and abdominal computed tomography revealed diffuse enlargement of the pancreas associated with a large cyst, measuring 8 cm in diameter. Endoscopic retrograde cholangiopancreatography revealed narrowing of the main pancreatic duct (from the body to the tail), narrowing of the intrapancreatic bile duct, and dilatation of the bile ducts. The patient was given a diagnosis of autoimmune pancreatitis (AIP) associated with a pancreatic pseudocyst and intrapancreatic bile duct stenosis. Oral steroid therapy resulted in reduced pancreatic swelling, complete disappearance of the pancreatic cyst, and an improvement in biliary stenosis. AIP is rarely associated with pancreatic cyst, and only 13 cases, including ours, have been reported to date. In our patient, intense inflammation apparently led to cyst formation in association with AIP, which responded remarkably to corticosteroid therapy. Correct diagnosis of AIP associated with a pancreatic pseudocyst might save patients from undergoing unnecessary endoscopic and surgical procedures.     

自身免疫性胰腺炎临床特征分析

目的 探讨自身免疫性胰腺炎(autoimmune pancreatitis,AIP)的临床特点,提高对AIP的认识,降低误诊率.方法 分析2006-2009年期间在解放军总医院诊治的AIP患者的临床表现、影像及病理学特征和诊疗经过,并与1995-2005年期间的本院资料进行对比.结果 2006-2009年期间诊治8例AIP患者(男6例,女2例),年龄35～69(52.4±9.4)岁.主要临床表现为黄疸6例(6/8),腹痛5例(5/8),伴有其他免疫疾病4例(4/8).影像学见胰腺局部肿大3例(3/8),弥漫性肿大5例(5/8),其胰周均可见"香蕉皮样"囊状环,胰管不规则狭窄.病理检查见胰腺组织、胆管、涎腺及肝内可见大量淋巴细胞和浆细胞浸润及实质纤维化.7例(7/8)口服泼尼松治疗后临床表现、实验室及影像学表现均明显好转.我院1995-2005年期间资料显示,95.7%(22/23)误诊为胆道或胰腺癌,91.3%(21/23)行开腹手术,自2006年以后无一例出现误诊(0/8).结论 AIP是全身免疫系统异常体现在胰腺的一种损伤,常伴发其他免疫性疾病,综合免疫指标检测、影像学、病理学检查及试验性糖皮质激素治疗等可获确诊.     

自身免疫性胰腺炎的CT和MRI影像学征象

目的 探讨自身免疫性胰腺炎(autoimmune pancreatitis,AIP)的CT及MRI影像学表现特征.方法 回顾性分析14例经组织学和(或)类固醇激素治疗证实的AIP患者的CT及MRI资料.10例行CT检查,7例行MRI检查(其中3例同时做CT和MRI检查).结果 11例AIP表现为胰腺弥漫性肿大,3例为胰腺局限性肿大.10例CT平扫见胰腺病变区密度均降低,5例显示节段性胰管,5例见胆总管胰头段狭窄;7例在胰腺病变区周围可见环绕包膜样结构;动态增强后出现延迟均匀强化.7例MRI的抑脂T1WI显示胰腺病变后信号均匀降低(3例)或不均匀降低(4例),抑脂T2WI信号均匀增高(3例)或不均匀增高(4例);4例MRI显示胰管,MRCP见1例胰头部胰管局限性狭窄,2例胰管节段性狭窄;5例MRI见胆总管胰头段狭窄,MRCP见3例胆总管胰头段呈鸟嘴样狭窄;6例见胰腺病变区周围环绕包膜样结构.14例AIP均未见胰腺实质钙化,胰管均未见明显扩张(＞3 mm).结论 AIP的CT、MRI表现具有特征性,主要为胰腺呈腊肠样改变,胰周出现包膜样结构,胰管弥漫性或局限性狭窄,胆总管胰头段炎性狭窄.     

Autoimmune sclerosing cholangiopancreatitis with little pancreatic involvements by imaging findings

Autoimmune pancreatitis is frequently associated with sclerosing cholangitis. A first clue for suspecting a case of autoimmune pancreatitis is enlargement of the pancreas. We encountered several sclerosing cholangitis cases within a short period, which showed no enlargement of the pancreas and in addition, some showed no irregular narrowing on endoscopic retrograde pancreatography, but they should belong to the same category of autoimmune pancreatitis. We report 5 cases and clarified their characteristics. All five cases showed no enlargement of the pancreas. Two cases showed segmental and one case had diffuse narrowing of the main pancreatic duct. The other two cases showed no irregular narrowing of the main pancreatic duct. Two cases were surgically treated. Two cases received steroid therapy. The other case was treated only by endoscopic biliary drainage. Pathological findings of the bile duct in the surgical specimens of two cases showed that there was a severe infiltration of lymphocytes, IgG4-positive plasmacytes and prominent fibrosis compatible with the findings of sclerosing lymphoplasmacytic cholangitis. We should recognize some sclerosing cholangitis cases showed no enlargement of the pancreas and no irregular narrowing of main pancreatic duct. We propose the concept of "autoimmune sclerosing cholangiopancreatitis".     

自身免疫性胰腺炎的内镜超声表现

目的 分析总结自身免疫性胰腺炎在内镜超声的特征表现.方法 回顾分析2004年8月至2007年9月确诊的11例原发性自身免疫性胰腺炎的临床资料,总结内镜超声的影像特点.结果 内镜超声下见胰腺实质回声极低,胰腺弥漫或局部增大,边缘呈波浪样改变;肝外胆管扩张,胆管壁明显增厚,呈均匀中低回声;可见胰腺周边淋巴结肿大.所有病例均未见明显胰管扩张或胰石、胰腺钙化和囊肿形成;未见周边血管受累.结论 自身免疫性胰腺炎在内镜超声下具有相对特征性的表现,有助于自身免疫性胰腺炎的临床诊断.     

Diagnosis of autoimmune pancreatitis: the Mayo Clinic experience.

BACKGROUND & AIMS: The Japan Pancreas Society criteria for diagnosis of autoimmune pancreatitis (AIP) mandate presence of characteristic imaging (diffuse pancreatic enlargement with diffusely irregular, narrow pancreatic duct). AIP has unique histologic features associated with infiltration of tissues of affected organs with abundant IgG4-positive cells. We propose expanded diagnostic criteria for AIP with a cohort of histologically confirmed AIP. METHODS: We reviewed the pancreatic imaging findings on computed tomography scans, serum IgG4 levels, other organ involvement, and response to steroids in 29 consecutive patients who met histologic criteria for AIP. RESULTS: Computed tomography scans (n = 22) showed diffuse pancreatic enlargement in 6 (27%) patients; the rest had focal enlargement, distinct mass, normal pancreas, or focal acute pancreatitis. Serum IgG4 level was elevated in 15 of 21 (71%) patients, and other organ involvement (eg, intrahepatic biliary strictures) was noted in 11 of 29 (38%) patients. All 17 patients treated with steroids exhibited resolution/marked improvement of pancreatic/extrapancreatic manifestation. On the basis of this experience we propose that diagnosis of AIP can be made in patients with > or =1 of these criteria: (1) diagnostic histology, (2) characteristic imaging on computed tomography and pancreatography with elevated serum IgG4 level, or (3) response to steroid therapy of pancreatic/extrapancreatic manifestations of AIP. Twenty additional patients met expanded diagnostic criteria for AIP, and their demographic and clinical profile was similar to that of the 29 patients meeting histologic criteria. CONCLUSIONS: AIP defined by histological criteria shows a wide spectrum of radiologic features, with characteristic imaging seen only in a minority. Incorporation of additional features into current diagnostic criteria can identify the full spectrum of clinical presentations of AIP.     

Clinical and imaging features of autoimmune pancreatitis with focal pancreatic swelling or mass formation: comparison with so-called tumor-forming pancreatitis and pancreatic carcinoma

OBJECTIVES: Autoimmune pancreatitis (AIP) with a mass formation or swollen pancreas located in one or two segments of the gland (focal type AIP) has been reported. The aims of this study were to elucidate the relationship of the disease entity between this focal variant and so-called tumor-forming pancreatitis (TFP) and to describe the clinical and imaging features discriminating focal AIP from pancreatic carcinoma (Pca). METHODS: The clinical, radiologic, and pathologic profiles of nine patients with focal AIP were reviewed retrospectively and compared with those of 11 patients with alcohol-induced TFP and 80 patients with Pca. RESULTS: The patients with focal AIP were predominantly older (mean age 64.7 +/- 13.6 yr, range 28-78 yr), male, and presenting with obstructive jaundice or focal pancreatic enlargement accompanied by mild abdominal symptoms. In comparison, the patients with alcohol-induced TFP who were mostly middle-aged (mean age 50.1 +/- 7.95 yr, range 39-62 yr), male, and often had attacks of pancreatitis associated with findings of CT scans showing pseudocysts or peripancreatic effusion. Focal AIP usually demonstrated no abnormalities on pancreatograms downstream from the stricture or obstruction and often presented few contrast-filled side branches in the area of main pancreatic duct (MPD) stenosis. These characteristics were similar to the imaging features of Pca. Significant factors differentiating focal AIP from Pca were lower serum levels of CA19-9, homogeneous delayed enhancement evident in dynamic CT scans, and ERCP findings exhibiting a longer stenosed MPD and a thinner MPD upstream from the stricture. CONCLUSIONS: Focal AIP is associated with clinical and radiologic features that are different from those of alcohol-induced TFP. In TFP there are two causative factors, namely, AIP and alcohol-induced chronic pancreatitis. Differential diagnosis of focal AIP from Pca seems to be possible in many cases by evaluating imaging findings such as dynamic CT and ERCP, although focal AIP sometimes shows clinical and radiologic features similar to those of Pca.     

Incidence of the focal type of autoimmune pancreatitis in chronic pancreatitis suspected to be pancreatic carcinoma: experience of a single tertiary cancer center

Objective. With an increase in autoimmune pancreatitis (AIP) being reported, the focal type of AIP, which shows localized narrowing of the main pancreatic duct and focal swelling of the pancreas, has recently been recognized. Therefore, cases of focal-type AIP subjected to surgical intervention for presumptive malignancy might previously have been diagnosed as mass-forming chronic pancreatitis. The aim of this study was to elucidate the incidence of focal-type AIP in resected chronic pancreatitis at a single tertiary cancer center. The clinical and radiological features of focal-type AIP were also evaluated. Material and methods. We re-evaluated 15 patients who underwent pancreatic resection with a presumed diagnosis of pancreatic ductal adenocarcinoma, and who in the past had been diagnosed pathologically as having chronic pancreatitis. Results. Seven of 15 patients showed AIP, and the other 8 patients were diagnosed as having mass-forming chronic pancreatitis not otherwise specified by pathological retrospective examination. In other words, nearly half of the cases of resected chronic pancreatitis that were suspected to be pancreatic carcinoma preoperatively showed focal-type AIP. Regarding the characteristic findings of focal-type AIP, narrowing of the pancreatic duct on endoscopic retrograde pancreatography (ERP) might be diagnostic. Conclusions. Focal-type AIP is not a rare clinical entity and might be buried in previously resected pancreatic specimens that in the past were diagnosed simply as mass-forming pancreatitis.     

I型自身免疫性胰腺炎的研究进展

自身免疫性胰腺炎（AIP）是逐渐被认识的慢性胰腺炎的一种类型,与其他类型的慢性胰腺炎有明显的不同。随着2001年发现AIP患者血清IgG4含量明显增高,这个现实被广泛的接受。1型AIP与2型AIP不同。2％的慢性胰腺炎为1一AIP,成人男性患者居多。患者通常由于胰头的增大或胆管壁增厚所致梗阻性黄疸,通过血清学、影像学和组织学与胰腺癌鉴别。血清IgG4水平的增高是最为敏感和特异性的表现。影像学的表现为胰管的不规则狭窄,胰腺弥散性或局灶性的扩大及胰周可见环形的囊壳样影,以及影像延迟期强化。组织学显示大量的dxDt问质表现为致密的纤维化伴席纹状、炎细胞浸润,闭塞性静脉炎和lgG4阳性细胞数量增加。激素治疗疗效明显是另外的特征,在初治的2～3周血清学和影像学明显改善。基于同步或不同步的伴有多器官的损伤,1一AIP也被认为是一种IgG4相关全身性疾病。至今有一些与1一AIP相关的自身免疫性抗原被鉴定,但IgG4在此病中的作用是肯定的。     

Autoimmune chronic pancreatitis

In recent years a peculiar type of chronic pancreatitis with underlying autoimmunity has been described. Lymphoplasmacytic infiltration and fibrosis on histology and elevated IgG levels or detected autoantibodies on laboratory data support the concept of autoimmune chronic pancreatitis (AIP). Pancreatic imaging reveals a rare association of diffuse enlargement of the pancreas and irregular narrowing of the main pancreatic duct, which is unique and specific to AIP. Although AIP is not a common disease, it is increasingly being recognized as knowledge of this entity builds up. Clinically it is very important to be aware of this disease because AIP can clinically disguise as pancreaticobiliary malignancies, ordinary chronic, or acute pancreatitis. Above all, AIP is a very attractive disease to clinicians in terms of its dramatic response to oral steroid therapy in contrast to ordinary chronic pancreatitis. This review discusses the clinical, laboratory, histologic, and imaging findings that are seen in patients with AIP, especially focusing on the diagnosis.     

Autoimmune pancreatitis with multifocal lesions

Two cases of a focal type of autoimmune pancreatitis (AIP) with distinct double mass lesions within the pancreas are described. In both patients, computed tomography (CT) showed localized pancreatic masses with delayed enhancement, and magnetic resonance cholangiopancreatography (MRCP) revealed localized stenoses of the main pancreatic duct (MPD) with mild upstream dilatation. Fluorodeoxyglucose positron emission tomography (FDG-PET) examination, performed in one patient, showed intense uptake concordant with tumors. Both patients received pancreatic resection with a presumptive diagnosis of pancreatic carcinoma. Histologic evaluation of the tumors showed marked lymphoplasmacytic infiltration and fibrosis around the large and medium pancreatic ducts, without any evidence of malignancy. Serum IgG4 concentration, measured postoperatively, was elevated in both patients. The characteristic morphological features of AIP are diffuse swelling of the pancreatic parenchyma and diffuse narrowing of the MPD. Recently, a focal type of AIP, which mimics pancreatic carcinoma, has been recognized. Considering the favorable response of AIP to steroid therapy, it is clinically important to differentiate the focal type of AIP from pancreatic carcinoma and to know that AIP sometimes exhibits multiple lesions within the pancreas.     

Asian diagnostic criteria for autoimmune pancreatitis: consensus of the Japan-Korea Symposium on Autoimmune Pancreatitis

In 2002, the Japan Pancreas Society (JPS) was the first in the world to propose diagnostic criteria for autoimmune pancreatitis (AIP). Since the concept of AIP has changed with the accumulation of AIP cases, the Research Committee of Intractable Pancreatic Diseases (RCIPD) provided by the Ministry of Health, Labour and Welfare of Japan and the JPS issued revised clinical diagnostic criteria of AIP in 2006. The Asan Medical Center of Korea also proposed diagnostic criteria for AIP in 2006. However, there are subtle but clinically challenging differences between the Japanese and Korean criteria. This inconsistency makes it difficult to compare data in studies from different centers and elucidate the characteristics of AIP. To reach a consensus on AIP, the RCIPD and the Korean Society of Pancreatobiliary Diseases established the following Asian criteria for the diagnosis of AIP: I-1. Imaging studies of pancreatic parenchyma show a diffuse/segmental/focally enlarged gland, occasionally with a mass and/or a hypoattenuation rim. I-2. Imaging studies of pancreaticobiliary ducts show diffuse/segmental/focal pancreatic ductal narrowing, often with stenosis of the bile duct. (Both I-1 and I-2 are required for diagnosis). II. Elevated level of serum IgG or IgG4, and detection of autoantibodies. III. Common lymphoplasmacytic infiltration and fibrosis, with abundant IgG4-positive cell infiltration. AIP should be diagnosed when criterion I and one of the other two criteria are satisfied, or when histology shows the presence of lymphoplasmacytic sclerosing pancreatitis in the resected pancreas. A diagnostic trial of steroid therapy can be applied carefully by expert pancreatologists only in patients fulfilling criterion I alone with negative diagnostic work-up results for pancreatobiliary cancer.     

Comparison of radiological and histological findings in autoimmune pancreatitis

BACKGROUND/AIMS: Autoimmune pancreatitis displays radiological findings that are sometimes difficult to differentiate from pancreatic carcinoma. To understand the essential radiological features of autoimmune pancreatitis (AIP), we compared imaging and histological findings in resected AIP specimens. METHODOLOGY: Findings of ultrasonography, computed tomography, endoscopic retrograde cholangiopancreatography and angiography were examined retrospectively for 6 patients who underwent pancreatoduodenectomy on suspicion of pancreatic carcinoma, and compared with histological findings of the resected specimens. RESULTS: Ultrasonography showed an enlarged hypoechoic pancreas with sausage-like appearance and no lobulation in the contour of the pancreas. On computed tomography imaging, delayed enhancement of the swollen pancreatic parenchyma became evident. Dense lymphoplasmacytic infiltration with fibrosis involving peripancreatic tissue was observed throughout almost the entire pancreas. Periductal non-occlusive fibrosis with lymphoplasmacytic infiltration induced narrowing of the pancreatic duct. Stenosis of the common bile duct is frequently associated with autoimmune pancreatitis and is induced by diffuse thickening of the duct wall by the same inflammatory process as that of the pancreas. The fibroinflammatory process also involves blood vessels. CONCLUSIONS: Characteristic radiological findings of autoimmune pancreatitis are induced with systemic histological changes of lymphoplasmacytic infiltration with fibrosis, and differ from schirrous invasion of pancreatic carcinoma.     

Atypical primary sclerosing cholangitis cases associated with unusual pancreatitis.

BACKGROUND/AIMS: We encountered one group of primary sclerosing cholangitis cases which met classic criteria, but demonstrated better clinical courses. METHODOLOGY: We evaluated the clinical characteristics of several cases of primary sclerosing cholangitis, especially those associated with chronic pancreatitis. RESULTS: Of a total of 25 cases, eight had a background of pancreatitis with unusual irregularly segmental or diffuse narrowing features on pancreatography. Abdominal ultrasonography and computed tomography also revealed segmental or diffuse enlargement of the pancreas. Pathological findings of surgical specimens in two cases pointed to lymphoplasmacytic sclerosing pancreatitis. The walls of the lower biliary ducts were also thickened with a similar appearance to the pancreatic ducts. In seven cases, cholangiography displayed stenosis of the lower part of the common bile duct and in one case, only the hepatic hilar region was affected. In this case both biliary and pancreatic lesions responded to steroid therapy simultaneously. One case developed hepatic hilar stenosis four months after a lesion in the lower part of the common bile duct had disappeared. The cases of primary sclerosing cholangitis with pancreatitis demonstrated better clinical courses than did typical cases of primary sclerosing cholangitis. Six cases were characterized by autoimmunological abnormalities. CONCLUSIONS: We concluded that similar etiological agents might impact on both the pancreas and biliary tract, either simultaneously or in sequence. We propose new criteria for these atypical primary sclerosing cholangitis cases.     

Diagnosis and management of autoimmune pancreatitis： Experience from China

AIM： To determine the clinical, radiographic and pathologic characteristics, diagnostic and treatment modalities in patients with autoimmune pancreatitis （AIP）. METHODS： In this retrospective study, the data of patients with diagnosed chronic pancreatitis （CP） between 1995 and 2006 in Chinese PLA General Hospital were included to screen for the cases with AIP, according to the following diagnostic criteria： （1） diagnostic histopathologic features, and abound IgG4-positive plasma cells on pancreatic tissues; （2） characteristic imaging on computed tomography and pancreatography, together with increased serum IgG, y-globulin levels or presence of autoantibodies; （3） response to steroid therapy. The clinical, radiographic and pathologic characteristics, diagnostic and treatment modalities, and outcome of AIP cases were reviewed. RESULTS： Twenty-five （22 male, 3 female; mean age 54 years, 36-76 years） out of 510 CP patients were diagnosed as AIP, which accounted for 49% （21/43） of CP population undergoing surgical treatment in the same period. The main clinical manifestations included intermittent or progressive jaundice in 18 cases （72%）, abdominal pain in 11 （44%）, weight loss in 10 （40%）, and 3 cases had no symptoms. The imaging features consisted of pancreatic enlargement, especially in the head of pancreas （18 cases）, strictures of main pancreatic duct and intrapancreatic bile duct. Massive lymphocytes and plasma cells infiltration in pancreatic tissues were showed on pathology, as well as parenchymal fibrosis. Twenty-three patients were misdiagnosed as pancreaticobiliary malignancy, and 21 patients underwent exploratory laparotomy, theremaining 4 patients dramatically responded to steroid therapy. No pancreatic cancer occurred during a mean 46-mo follow-up period. CONCLUSION： AIP patients always are subjected to mistaken diagnosis of pancreatic cancer and an unnecessary surgical exploration, due to its similarity in clinical features with pancreatic cancer. T