Diffuse pancreatic fibrosis: an uncommon feature of multifocal idiopathic fibrosclerosis

IgG4-related sclerosing disease, an emerging entity: a review of a multi-system disease

Immunoglobulin G4-related systemic disease (IgG4-RSD) is a recently defined emerging entity characterized by a diffuse or mass forming inflammatory reaction rich in IgG4-positive plasma cells associated with fibrosclerosis and obliterative phlebitis. IgG4-RSD usually affects middle aged and elderly patients, with a male predominance. It is associated with an elevated serum titer of IgG4, which acts as a marker for this recently characterized entity. The prototype is IgG4-related sclerosing pancreatitis or autoimmune pancreatitis (AIP). Other common sites of involvement are the hepatobiliary tract, salivary gland, orbit, and lymph node, however practically any organ can be involved, including upper aerodigestive tract, lung, aorta, mediastinum, retroperitoneum, soft tissue, skin, central nervous system, breast, kidney, and prostate. Fever or constitutional symptoms usually do not comprise part of the clinical picture. Laboratory findings detected include raised serum globulin, IgG and IgG4. An association with autoantibody detection (such as antinuclear antibodies and rheumatoid factor) is seen in some cases. Steroid therapy comprises the mainstay of treatment. Disease progression with involvement of multiple organ-sites may be encountered in a subset of cases and may follow a relapsing-remitting course. The principal histopathologic findings in several extranodal sites include lymphoplasmacytic infiltration, lymphoid follicle formation, sclerosis and obliterative phlebitis, along with atrophy and destruction of tissues. Immunohistochemical staining shows increased IgG4+ cells in the involved tissues (>50 per high-power field, with IgG4/IgG ratio >40%). IgG4-RSD may potentially be rarely associated with the development of lymphoma and carcinoma. However, the nature and pathogenesis of IgG4-RSD are yet to be fully elucidated and provide immense scope for further studies.

IgG₄-related sclerosing disease: a novel mimic of inflammatory bowel disease

High levels of IgG₄-positive plasma cells are commonly seen in autoimmune pancreatitis. It has recently become evident that autoimmune pancreatitis is one component of a larger multi-system disease. IgG₄-positive plasma cells have been identified in many extrapancreatic tissues, including the colon, biliary tract, liver, and lungs, and thus the term "IgG₄-related sclerosing disease" has been proposed. Awareness of IgG₄-related sclerosing disease is important, as it has been shown to mimic other conditions like malignancy. This review discusses IgG₄-related colitis and its potential for mimicking inflammatory bowel disease.

IgG4-related sclerosing disease: a critical appraisal of an evolving clinicopathologic entity

An elevated serum titer of immunoglobulin G4 (IgG4), the least common (3% to 6%) of the 4 subclasses of IgG, is a surrogate marker for the recently characterized IgG4-related sclerosing disease. The syndrome affects predominantly middle-aged and elderly patients, with male predominance. The patients present with symptoms referable to the involvement of 1 or more sites, usually in the form of mass lesions. The prototype is IgG4-related sclerosing pancreatitis (also known as autoimmune pancreatitis), most commonly presenting as painless obstructive jaundice with or without a pancreatic mass. Other common sites of involvement are the hepatobiliary tract, salivary gland, orbit, and lymph node, but practically any organ-site can be affected, such as retroperitoneum, aorta, mediastinum, soft tissue, skin, central nervous system, breast, kidney, prostate, upper aerodigestive tract, and lung. The patients usually have a good general condition, with no fever or constitutional symptoms. Common laboratory findings include raised serum globulin, IgG, IgG4, and IgE, whereas lactate dehydrogenase is usually not raised. Some patients have low titers of autoantibodies (such as antinuclear antibodies and rheumatoid factor). The disease often shows excellent response to steroid therapy. The natural history is characterized by the development of multiple sites of involvement with time, sometimes after many years. However, the disease can remain localized to 1 site in occasional patients. The main pathologic findings in various extranodal sites include lymphoplasmacytic infiltration, lymphoid follicle formation, sclerosis and obliterative phlebitis, accompanied by atrophy and loss of the specialized structures of the involved tissue (such as secretory acini in pancreas, salivary gland, or lacrimal gland). The relative predominance of the lymphoplasmacytic and sclerotic components results in 3 histologic patterns: pseudolymphomatous, mixed, and sclerosing. Immunostaining shows increased IgG4+ cells in the involved tissues (>50 per high-power field, with IgG4/IgG ratio >40%). The lymph nodes show multicentric Castleman disease-like features, reactive follicular hyperplasia, interfollicular expansion, or progressive transformation of germinal centers, with the unifying feature being an increase in IgG4+ plasma cells on immunostaining. The nature and pathogenesis of IgG4-related sclerosing disease are still elusive. Occasionally, the disease can be complicated by the development of malignant lymphoma and possibly carcinoma.

Nonneoplastic mimickers of pancreatic neoplasms

CONTEXT

A variety of nonneoplastic conditions may form pancreatic masses that mimic carcinoma. Approximately 5% to 10% of pancreatectomies performed with the clinical diagnosis of pancreatic cancer prove on microscopic evaluation to be pseudotumors.

OBJECTIVES

To illustrate the clinical and pathologic characteristics of the 2 most frequent pseudotumoral inflammatory conditions, autoimmune pancreatitis and paraduodenal pancreatitis, and describe the criteria that may be useful in the differential diagnosis versus pancreatic carcinoma.

DATA SOURCES

Recent literature and the authors' experience with the clinical and pathologic characteristics of autoimmune pancreatitis and paraduodenal pancreatitis.

CONCLUSIONS

The knowledge of the clinical, radiologic, and pathologic findings in both autoimmune pancreatitis and paraduodenal pancreatitis is crucial in making the correct preoperative diagnosis. Autoimmune pancreatitis, which occurs in isolated or syndromic forms, is characterized by a distinctive fibroinflammatory process that can either be limited to the pancreas or extend to the biliary tree. Its correct preoperative identification on biopsy material with ancillary immunohistochemical detection of dense immunoglobulin G4-positive plasma cell infiltration is possible and crucial to prevent major surgery and to treat these patients with steroid therapy. Paraduodenal pancreatitis is a special form of chronic pancreatitis that affects young males with a history of alcohol abuse and predominantly involves the duodenal wall in the region of the minor papilla. Pathogenetically, the anatomical and/or functional obstruction of the papilla minor, resulting from an incomplete involution of the intraduodenal dorsal pancreas, associated with alcohol abuse represents the key factor. Endoscopic drainage of the papilla minor, with decompression of the intraduodenal and dorsal pancreas, might be considered in these patients.

Abdominal extrapancreatic lesions associated with autoimmune pancreatitis: Radiological findings and changes after therapy

PURPOSE

To evaluate imaging findings of abdominal extrapancreatic lesions associated with autoimmune pancreatitis (AIP) and changes after steroid therapy.

METHODS AND MATERIALS

This study included nine AIP patients with abdominal extrapancreatic lesions, which were determined by retrospective radiological review. CT (initial and follow-up, n=9) and MR imaging (initial, n=5) were reviewed by two radiologists in consensus to determine imaging characteristics (i.e., size, number, attenuation or signal intensity, and contrast enhancement of the lesions, and the presence of overlying capsule retraction) and evaluate changes with steroid therapy of abdominal extrapancreatic lesions associated with AIP.

RESULTS

The most common abdominal extrapancreatic lesion associated with AIP was retroperitoneal fibrosis (RPF) in six patients. In five patients, CT and MR imaging revealed single or multiple, round- or wedge-shaped, hypoattenuating or hypointense, enhancing lesions in the renal cortex or pelvis. Other lesions included a geographic, ill-defined, hypoattenuating lesion with or without overlying capsule retraction in the liver in two and bile duct dilatation with or without bile duct wall thickening in four. Over a follow-up period of 6-81 months, CT exams of eight patients demonstrated partial or complete improvement of the abdominal extrapancreatic lesions, albeit their improvement in general lagged behind that of the pancreatic lesion.

CONCLUSION

On CT or MR imaging, the abdominal extrapancreatic lesions associated with AIP are various in the retroperitoneum, liver, kidneys and bile ducts, and are reversible with steroid therapy.

Manifestations salivaires dans la Maladie Fibrosclérosante Multiple à IgG4

OBJECTIVES

To report a case of IgG4-related multifocal fibrosclerosis, revealed by a multifocal salivary involvement.

MATERIAL AND METHODS

A 59-year-old man, with chronic pancreatitis, was managed for fibrotic involvement of the 2 submaxillary glands and the 2 parotids. Clinical, radiological, and histologic features were retrospectively studied.

RESULTS

Pathological features of submandibular gland revealed a chronic sclerosing sialadenitis. Retroperitoneal fibrosis in computed tomography and high rate of IgG4 are objectived. The diagnosis of IgG4-related multifocal fibrosclerosis is evoked. The patient's state improved with corticosteroid therapy.

CONCLUSION

Salivary involvement in IgG4-related multifocal fibrosclerosis must be recognized in salivary medical pathology.

Systemic extrapancreatic lesions associated with autoimmune pancreatitis

Autoimmune pancreatitis (AIP) is frequently associated with sclerosing cholangitis (SC). SC with AIP has a cholangiographic appearance that is often confused with primary sclerosing cholangitis (PSC) but only the former responds well to corticosteroid therapy. Detailed study of cholangiographic findings allows discrimination of SC with AIP from PSC. Band-like strictures, a beaded or pruned-tree appearance, and diverticulum-like outpouching were significantly more frequently observed in cases of PSC. In contrast, segmental strictures, dilation after confluent stricture, and strictures of the lower common bile duct were significantly more common in SC with AIP. The other systemic extrapancreatic lesions associated with AIP found in the literature were Sjögren's syndrome, ulcerative colitis, retroperitoneal fibrosis, sialadenitis, thyroiditis, and idiopathic thrombocytopenic purpura. In a comparison of the clinical course and laboratory data of our cases, gamma-globulin, IgG, and IgG4 levels were significantly higher in patients with AIP with systemic extrapancreatic lesions than those without them. In our immunohistochemical study, marked infiltration of IgG4+ plasma cells was frequently observed in the pancreas, liver, bile duct, and salivary glands of the AIP patients examined. In contrast, the degree of infiltration of IgG4+ plasma cells around the bile duct in the portal areas and the extrahepatic bile duct with PSC was significantly lower than with AIP. These results also suggest that AIP is a disease state clearly different from PSC. In addition, the normal epithelia of the pancreatic ducts, bile ducts, gallbladder, and salivary gland ducts reacting with the patients' sera was detectable by the anti-IgG4 antibody. Therefore, AIP may also affect extrapancreatic organs, and the sera of AIP patients may contain an IgG4 autoantibody to various organs.

Autoimmune pancreatocholangitis: a series of ten patients

BACKGROUND

During a 10-year period we observed 10 patients who suffered from an inflammatory-fibrosing disease mimicking pancreatic carcinoma and primary sclerosing cholangitis (PSC).

METHODS

A review of the presenting features, the clinical course and the relevant literature.

RESULTS

Ten male patients (mean age 55 years) presented with weight loss, jaundice and pruritus. Pancreatic cancer was suggested by imaging studies, which showed focal or generalized pancreatic enlargement and compression of the distal common bile duct. Cholangiography also demonstrated intrahepatic biliary stenoses consistent with sclerosing cholangitis. None had evidence of IBD. Exocrine pancreatic insufficiency was found in six cases and diabetes in four. Pancreatic histology (n=3) showed fibrosis and extensive inflammatory infiltrates. Immunosuppressive treatment was instituted in five patients. Clinical and biochemical remission occurred in three; in one other patient, previously documented intrahepatic biliary strictures had disappeared after 3 months. One patient had concomitant Sjögren's disease. The clinical features, pancreatic involvement, age at presentation, absence of IBD and response to steroids all plead against a diagnosis of "classical" PSC. The natural course of the disease was highly variable. Thirty-five comparable cases, with a largest series of three, have been reported in the literature. The disease has been associated with Sjögren's disease, retroperitoneal fibrosis and other fibrosing conditions, and may be a manifestation of a systemic fibro-inflammatory disorder.

CONCLUSION

Autoimmune pancreatocholangitis is a distinct inflammatory disorder involving the pancreas and biliary tree. The disease may mimick pancreatic carcinoma and PSC and responds to immunosuppressives.

Difficulty in diagnosing autoimmune pancreatitis by imaging findings

BACKGROUND

Autoimmune pancreatitis (AIP) presents as diffuse enlargement of the pancreas and as diffuse irregular narrowing of the main pancreatic duct. However, some AIP cases are difficult to diagnose because of atypical imaging findings.

OBJECTIVE

To clarify a variety of imaging findings of AIP and the reason for its misdiagnosis.

DESIGN

We examined the imaging findings of 37 AIP cases and also examined misdiagnosed cases of AIP to determine their reasons for misdiagnosis.

PATIENTS

A total of 37 patients with AIP who reported to our hospital or its affiliate over a 17-year period (1989 to May 2005).

RESULTS

Patients in 15 AIP cases showed segmental narrowing of the main pancreatic duct. There were 6 patients with focal enlargement of the pancreas, whereas 3 patients showed no enlargement. There were 3 cases of calcification of the pancreas. Pancreatic cysts were detected in 2 patients. Abdominal US showed multiple low-echoic masses in 1 case and a single mass in 3 cases. Sixteen patients had stenosis of the bile duct at the hilar hepatic lesion and/or the intrahepatic duct. Only 7 patients had typical AIP findings. Six patients were misdiagnosed with pancreatic cancer and 2 with bile-duct cancer. Seven cases were surgically treated. Five cases were misdiagnosed because of the nonexistence of, or the unfamiliarity with, the concept of AIP and sclerosing cholangitis with AIP. Another 3 cases were diagnosed with pancreatic cancer because of segmental stenosis of the main pancreatic duct and no or focal enlargement of the pancreas.

CONCLUSIONS

The results of this study suggest that AIP presents a variety of imaging findings. The most important diagnostic factor is clinician awareness of the concept of AIP and the diverse nature of imaging findings.

Autoimmune pancreatitis with retroperitoneal fibrosis which responded to steroid therapy but was complicated with refractory renal dysfunction

A 58-year-old male had been diagnosed as having autoimmune pancreatitis (AIP) from the results of serological examinations and image findings. He was treated with prednisolone (PSL) for 3.5 months. Fifteen months later, follow-up CT revealed the main pancreatic duct (MPD) dilatation in the pancreas body to tail and right hydronephrosis caused by complicated retroperitoneal mass. We diagnosed him as having recurrent AIP with retroperitoneal fibrosis, and restarted PSL treatment. After one month, Examinations indicated amelioration of the MPD dilatation and right hydronephrosis, but not the right renal failure. This case indicates the importance of maintenance of PSL treatment.

An external cause for 'idiopathic' pachymeningitis?

In a 67-year-old man with a history of professional asbestos exposure and persistent headaches since one year, a diagnosis of idiopathic pachymeningitis was made. IHCP (idiopathic hypertrophic cranial pachymeningitis) is in literature referred to as one of the presentations of Multifocal Idiopathic Fibrosclerosis or MIF, representing a group of fibro-inflammatory and pathologically similar diseases, including also retroperitoneal fibrosis, mediastinal fibrosis and sclerosing cholangitis. Since recent literature links asbestos exposure to a risk of development of retroperitoneal fibrosis, the present case suggests to focus in future research of IHCP on possible external causes.

Autoimmune pancreatitis associated with idiopathic retroperitoneal fibrosis: a case report

A 69-year-old man presented with obstructive jaundice and dark urine. Contrast-enhanced computed tomography revealed an enlarged pancreas with homogenous enhancement. Endoscopic retrograde pancreatography demonstrated short-segmental, irregular narrowing of the main pancreatic duct. The patient underwent exploratory laparotomy and needle biopsies of the pancreas, which showed marked fibrotic change with lymphocyte infiltration. These clinicopathologic findings suggested autoimmune pancreatitis. Four years later, computed tomography demonstrated marked periaortic soft tissue surrounding a calcified infrarenal abdominal aorta compatible with retroperitoneal fibrosis. We diagnosed retroperitoneal fibrosis with noncontiguous pancreatic fibrosis. This patient responded well to corticosteroid treatment. Autoimmune pancreatitis associated with idiopathic retroperitoneal fibrosis seems to be extremely rare, and to our knowledge, only a few cases have been reported.

Autoimmune pancreatitis: proposal of IgG4-related sclerosing disease

Autoimmune pancreatitis (AIP) is a peculiar type of pancreatitis of presumed autoimmune etiology. Many new clinical aspects of AIP have been clarified during the past 10 years, and AIP has become a distinct entity recognized worldwide. However, its precise pathogenesis or pathophysiology remains unclear. As AIP dramatically responds to steroid therapy, accurate diagnosis of AIP is necessary to avoid unnecessary surgery. Characteristic dense lymphoplasmacytic infiltration and fibrosis in the pancreas may prove to be the gold standard for diagnosis of AIP. However, since it is difficult to obtain sufficient pancreatic tissue, AIP should be diagnosed currently based on the characteristic radiological findings (irregular narrowing of the main pancreatic duct and enlargement of the pancreas) in combination with serological findings (elevation of serum gamma-globulin, IgG, or IgG4, along with the presence of autoantibodies), clinical findings (elderly male preponderance, fluctuating obstructive jaundice without pain, occasional extrapancreatic lesions, and favorable response to steroid therapy), and histopathological findings (dense infiltration of IgG4-positive plasma cells and T lymphocytes with fibrosis and obliterative phlebitis in various organs). It is apparent that elevation of serum IgG4 levels and infiltration of abundant IgG4-positive plasma cells into various organs are rather specific to AIP patients. We propose a new clinicopathological entity, "IgG4-related sclerosing disease", and suggest that AIP is a pancreatic lesion reflecting this systemic disease.

IgG4-associated prostatitis complicating autoimmune pancreatitis

A 65-year-old man underwent transurethral resection of the prostate on a diagnosis of benign prostatic hypertrophy. Almost simultaneously, a diagnostic resection of minor salivary glands was performed. After the resections he suffered from obstructive jaundice. Laboratory examinations revealed an increase in eosinophils and an elevation of serum IgG4. Pancreaticoduodenectomy was performed because of the possibility of pancreatic cancer. The prostate, salivary glands and pancreas showed common histological characteristics, namely, infiltration of lymphocytes and plasma cells accompanying dense fibrosis. Most of the infiltrating plasma cells showed strong immunoreactivity to IgG4. This is the first case with IgG4-associated prostatitis complicating autoimmune pancreatitis.

Pancreatic pseudotumors: non-neoplastic solid lesions of the pancreas that clinically mimic pancreas cancer

In the pancreas, a variety of non-neoplastic conditions may form solid masses that may mimic cancer. Up to 5% of pancreatectomies performed with the preoperative clinical diagnosis of carcinoma will prove to be non-neoplastic by pathologic examination, although this figure is decreasing with improved diagnostic modalities. Chronic inflammatory lesions are the leading cause of this phenomenon ("pseudotumoral pancreatitis"), and among these, autoimmune and paraduodenal pancreatitides (discussed separately in this issue) are most important. In this article, we will focus on the noninflammatory lesions that may form tumor-like lesions of the pancreas. Adenomyomatous hyperplasia of ampulla of Vater is a subtle lesion that is difficult to define; larger examples (>5 mm) have been found to be the cause of obstructive jaundice. Accessory (heterotopic) spleen may form a well-defined nodule within the tail of the pancreas and is typically mistaken for endocrine neoplasm. Lipomatous hypertrophy is the replacement of pancreatic tissue with mature adipose tissue that occasionally leads to moderate to marked enlargement of the pancreas. Hamartomas are very rare if the entity is defined strictly. They are characterized by irregularly arranged mature pancreatic elements admixed with stromal tissue. A cellular, spindle-cell variant with c-kit (CD117) expression is recognized. Pseudolymphoma forms well-defined nodules composed of hyperplastic lymphoid tissue. Rarely, foreign-body deposits, granulomatous inflammations (such as sarcoidosis or tuberculosis), and congenital lesions may form tumoral lesions. In conclusion, it is important to recognize the types of conditions that form pseudotumors in the pancreas so that they can be distinguished from ductal adenocarcinomas, especially clinically, but also pathologically. Nonspecific terms such as "inflammatory pseudotumor" ought to be avoided, and every attempt should be made to classify a "pseudotumor" into a more specific diagnostic category discussed above.

Diagnostic features and differential diagnosis of autoimmune pancreatitis

A clinically and pathologically distinct form of chronic pancreatitis is now widely recognized and has been designated variably as lymphoplasmacytic sclerosing pancreatitis, duct-destructive (duct-centric) pancreatitis or autoimmune pancreatitis. This entity is currently defined by a constellation of clinical and pathologic findings, including the lack of both conventional risk factors for pancreatitis, such as alcohol use and gallstones, and their hallmark pattern of injury, including calcifications and pseudocysts. Histologically, it is characterized by lymphoplasmacytic inflammation with abundant IgG4-positive plasma cells that exhibit an affinity for ducts as well as venules ("peri-venulitis," with or without frank vasculitis). Inflammation is often associated with sclerosis and expansion of periductal tissue. In some cases, fibroblastic activity is prominent and resembles "inflammatory pseudotumor" or is even misdiagnosed as "inflammatory myofibroblastic tumor." In what appears to be a distinct subset of this entity, intraepithelial granulocytic infiltrates may be seen. Well-developed examples are readily recognized; however, lesser ones may be difficult to distinguish from other forms of pancreatitis based on morphology alone. This type of pancreatitis is considered an autoimmune process. In about 15% to 20% of patients, the clinical stigmata of autoimmune conditions are present at the time of diagnosis, and in many others, discovered subsequently. The usual "lymphoplasmacytic sclerotic" type tends to be associated with Sjogren, whereas the "granulocytic" subset, with inflammatory bowel disease. Most patients present with a pancreatic head mass, often with an accompanying stricture of the distal common bile duct, which thus radiologically resembles "pancreas cancer." In fact, this entity accounts for more than a third of the cases of pseudotumoral pancreatitis (mass-forming inflammatory lesions that resemble carcinoma). Elevated serum IgG4 levels are characteristic and may be very helpful in the differential diagnosis from tumors and tumor-like lesions of the pancreas which seldom result in levels above 135 mg/dL. The mean age of the patients with this condition is in the mid-50s; the subset with granulocytic intraepithelial lesions seem to be younger (mid 40s). Despite the autoimmune association, males are afflicted as commonly as (if not more than) females. Following resection, emergence of new fibro-inflammatory lesions in the remaining pancreaticobiliary tree has been noted in some cases; however, the process typically responds to steroids. It is important to recognize the distinctive clinicopathologic features of this entity, so that it can be diagnosed accurately and managed appropriately.

Systemic extrapancreatic lesions associated with autoimmune pancreatitis

OBJECTIVES

Autoimmune pancreatitis (AIP) is often associated with systemic extrapancreatic lesions. We studied 31 cases of AIP to clarify the diversity of associated systemic extrapancreatic lesions and the differences between AIP with and without systemic extrapancreatic lesions.

METHODS

The clinical features and courses were compared by age, sex, and blood chemistry between those with and without systemic extrapancreatic lesions. In addition, we reviewed the available literature on systemic extrapancreatic lesions with AIP.

RESULTS

Seven of the 31 cases of AIP had associated systemic extrapancreatic lesions, which were diagnosed simultaneously with AIP; however, 1 case presenting with various extrapancreatic lesions was diagnosed independently of the AIP lesion. Patients with systemic extrapancreatic lesions needed maintenance steroid therapy for AIP in 4 cases and systemic extrapancreatic lesions in 2 cases; the ratio of cases requiring maintenance steroid therapy was significantly higher among those with systemic extrapancreatic lesions (6/8) than those without (7/23). There were no significant differences between groups with regard to age, sex, extent of narrowing of the main pancreatic duct, and enlargement of the pancreas. gamma-globulin, IgG, and IgG4 levels were significantly higher in patients with AIP with systemic extrapancreatic lesions than those without. The systemic extrapancreatic lesions associated with AIP found in the literature were Sjögren syndrome, ulcerative colitis, retroperitoneal fibrosis, sialadenitis, thyroiditis, and idiopathic thrombocytopenic purpura.

CONCLUSIONS

The results of this study suggest that, when encountering a case of AIP with elevated levels of gamma-globulins, IgG, and IgG4, an effort should be made to detect other systemic extrapancreatic abnormalities and initiate steroid administration.

Idiopathic fibrosclerosis of bilateral orbits, bilateral ureters, thyroid: A case report and review of the literature

INTRODUCTION

Idiopathic multifocal fibrosclerosis is a rare disorder which is usually misdiagnosed in the clinics. We try to make a review of the literature about this large spectrum syndrome and treatment modalities other than surgery. Our patient interestingly have both fibrosclerosis of bilateral ureters, orbits and thyroid. Steroids, radiotherapy, tamoxifen, vitaminD3, colchisine was found to be in effective in treatment of progressive fibrosis.

Lymphoplasmacytic sclerosing (autoimmune) pancreatitis

Lymphoplasmacytic sclerosing pancreatitis (LPSP), also known as autoimmune pancreatitis or nonalcoholic, duct destructive chronic pancreatitis, has been increasingly recognized in the past decade as a histologically distinctive type of pancreatitis that affects middle-aged patients who lack the typical risk factors for chronic pancreatitis (alcohol abuse in particular). LPSP is sometimes associated with other autoimmune diseases or fibroinflammatory lesions, although in some patients, pancreatic and biliary involvement represent the only known disease process. Many patients present with pancreatic masses clinically and radiographically simulating pancreatic carcinoma, and associated bile duct strictures enhance the resemblance. Elevated serum IgG4 levels have been described in patients with LPSP and have been used to distinguish LPSP from pancreatic carcinoma preoperatively. Although there is some heterogeneity of pathologic findings, resected cases of LPSP typically demonstrate dense periductal lymphoplasmacytic inflammation, periductal and parenchymal fibrosis, and obliterative venulitis; neutrophilic infiltration of the ductal epithelium ("granulocytic epithelial lesions") may also occur. Large tumor-like masses of fibroinflammatory tissue ("reactive fibroinflammatory pseudotumors") may develop and extend beyond the pancreas. Following surgical resection, a few patients suffer recurrence of fibroinflammatory lesions in the pancreatobiliary tree, or they may develop other manifestations of autoimmune disease elsewhere in the body. However, the overall prognosis is excellent. Response to steroid therapy has been noted. Current studies are focusing on identifying additional preoperative diagnostic tests and on characterizing possible variants of LPSP. This review presents the defining clinical and pathologic features of LPSP and discusses the ongoing efforts to understand the pathogenesis of this disease.

Pancreatic pseudotumor with sclerosing pancreato-cholangitis: is this a systemic disease?

OBJECTIVE AND METHOD

Primary sclerosing cholangitis (PSC) is a disease that predominantly affects the biliary tree, although the pancreas may also be affected. A review of the presenting features of all patients given a diagnosis of PSC at a single center was conducted. The aim was to clarify the presentation of patients with pseudotumor of the pancreas in this patient population.

RESULTS

Seventy-two patients were diagnosed with PSC either by ERCP (63/72 = 88%) or by liver biopsy (9/72 = 12%). The diagnosis of PSC was made following referral for abnormal liver tests (67%), jaundice (17%), and acute cholangitis (5%). Inflammatory bowel disease (IBD) (60%), non-insulin-dependent diabetes mellitus (NIDDM) (13%), thyroid disease (8%), and pancreatic disease (7%) were the major coexistent extrahepatic diseases. Three patients, all with marked weight loss, who presented with jaundice, abdominal pain, and/or diarrhea were found to have a pancreatic mass at first presentation. Clinical and radiological findings suggested pancreatic malignancy, and only later was advanced sclerosing cholangitis identified. The biopsy of the pancreas in two of these three patients revealed chronic pancreatitis. The long-term follow-up and good clinical response to medical therapy confirmed lack of pancreatic malignancy. These three patients all had other evidence of systemic involvement: submandibular gland fibrosis and urethral stricture in one, fibromuscular dysplasia of the renal artery in another, and retroperitoneal fibrosis in the third. None had IBD.

CONCLUSION

Pancreatic pseudotumor with sclerosing pancreato-cholangitis may be a manifestation of a systemic disease characterized by nonmalignant strictures and multifocal fibroinflammatory processes, unlike classical PSC.

Involvement of the biliary system in autoimmune pancreatitis: a follow-up study

BACKGROUND & AIMS

The aim of this study was to define the bile duct changes associated with autoimmune pancreatitis.

METHODS

Eight patients with autoimmune pancreatitis were followed for a mean of 4 years. The clinical features of these patients, including extrapancreatic bile duct changes, were examined by using biochemical parameters and several imaging modalities. Pathologic features of the pancreas and liver were examined by using the biopsy specimens of 7 patients.

RESULTS

Diffuse or focal narrowing of the main pancreatic duct was observed in all patients. Histologic examination of the pancreas showed lymphoplasmacyte infiltration with severe fibrosis and acinar cell depletion. In 6 patients extrapancreatic bile duct changes such as stricture of the bile duct at hilus or intrahepatic area were observed. In 2 patients abnormalities in the bile duct and pancreas were detected simultaneously at diagnosis, and changes in the bile duct were observed later in 4 patients. Lymphoplasmacyte infiltration and fibrosis were observed in the portal area of all 7 liver biopsy samples. Five of the patients with bile duct changes received steroid therapy, and the pathological changes improved.

CONCLUSIONS

Extrapancreatic bile duct changes are frequently associated with autoimmune pancreatitis. Similar pathogenic mechanism might produce the biliary tract and pancreatic abnormalities in autoimmune pancreatitis resulting in a similar histopathology in the liver and pancreas and response to steroid therapy.

Idiopathic chronic pancreatitis with periductal lymphoplasmacytic infiltration: clinicopathologic features of 35 cases

To clarify clinicopathologic features of idiopathic chronic pancreatitis with lymphoplasmacytic infiltration, we carried out a study of 35 cases. There were two histologic groups, which we have designated lymphoplasmacytic sclerosing pancreatitis and idiopathic duct-centric chronic pancreatitis. Lymphoplasmacytic sclerosing pancreatitis (22 cases) was a fibrosing process with diffuse lymphoplasmacytic infiltrates involving pancreatic lobules and ducts, adipose tissue, blood vessels, and common bile duct. Obliterative phlebitis was found in every case except for one. The histologic features were similar to other idiopathic fibrosclerosing disorders, and one patient also had retroperitoneal fibrosis. Affected patients tended to be elderly men. Idiopathic duct-centric chronic pancreatitis (13 cases) was characterized by inflammatory infiltrates (including neutrophils) that were denser in the lobules than in interlobular fibrotic areas. Neutrophils were also prominent in the ducts, and destruction of the duct epithelium was commonly seen. Patient ages were more broadly distributed than in lymphoplasmacytic sclerosing pancreatitis. Two patients had inflammatory bowel disease. We conclude that idiopathic chronic pancreatitis with lymphoplasmacytic infiltration, sometimes called autoimmune pancreatitis, consists of at least two different processes. One of these, lymphoplasmacytic sclerosing pancreatitis, is a histologically unique lesion and could be a pancreatic manifestation of idiopathic fibrosclerosing disorders.

Sclerosing inflammation in the orbit and in the pterygopalatine and infratemporal fossae

PURPOSE

To describe two cases with sclerosing inflammation in the orbit and in the pterygopalatine and infratemporal fossae and to review the literature of head and neck idiopathic inflammation.

METHODS

Interventional case series. Two clinical case reports of sclerosing inflammation in the orbits and in the pterygopalatine and infratemporal fossae are presented. A review of the literature and discussion was performed.

RESULTS

Both patients had histologic findings typical of chronic orbital sclerosing inflammation, including mature lymphocytes associated with dense collagen deposition and occasional lymphoid follicles. Bone erosion was present in one patient.

CONCLUSIONS

The clinical findings of this case series concur with the literature that idiopathic inflammation can be found simultaneously in the orbit and in the infratemporal and pterygopalatine fossae. These cases of idiopathic inflammation are often clinically indistinguishable from malignant neoplasms.

Idiopathic tumefactive chronic pancreatitis: clinical profile, histology, and natural history after resection

BACKGROUND & AIMS

Little is known about subjects with idiopathic tumefactive chronic pancreatitis (TCP), that is, chronic pancreatitis whose clinical presentation, usually with a mass or obstructive jaundice, suggests cancer.

METHODS

We independently reviewed clinical data and histology of 45 TCP (27 idiopathic, 18 alcohol induced) resected at Mayo Clinic (January 1985-March 2001). Follow-up data were obtained from medical records and mailed questionnaires.

RESULTS

Compared with alcoholic subjects, idiopathic TCP patients were older (58 +/- 2 vs. 48 +/- 3 yr, P < 0.001), had shorter symptom duration (median 3 vs. 24 wk, P < 0.001), were more likely to have no or mild abdominal pain (70% vs. 17%, P = 0.001), and were more often jaundiced (67% vs. 33%, P = 0.02). Three distinct histologic patterns were identified in TCP. Typical CP (n = 19) showed lobular atrophy, fat necrosis, and ductal changes (dilatation, protein plugs, and stones). Lymphoplasmacytic sclerosing pancreatitis (LPSP) (n = 14) was characterized by periductal lymphoplasmacytic infiltration, obliterative phlebitis, and cholangitis with edema. Idiopathic duct-centric CP (IDCP) (n = 12) had neutrophil-predominant lobular inflammation, without phlebitis. On correlation of clinical and histologic diagnosis, 17 of 18 (94%) patients with alcohol-induced TCP had typical CP, and 25 of 27 (93%) with idiopathic TCP had LPSP or IDCP. LPSP and IDCP were indistinguishable clinically except for higher incidence of jaundice in LPSP (93% vs. 42%, P = 0.005). In idiopathic TCP no recurrence of symptoms was observed after resection (median follow-up 49 mo).

CONCLUSIONS

Idiopathic TCP is clinically and histologically distinct from alcohol-induced TCP. It is unclear whether LPSP and IDCP, 2 unique patterns of histologic injury observed in idiopathic TCP, are part of the spectrum of the same disease or represent 2 or more different entities. Resection of mass prevents recurrence of symptoms in idiopathic TCP.

Hydronephrosis associated with retroperitoneal fibrosis and sclerosing pancreatitis

Sclerosing pancreatitis is associated with raised concentrations of IgG4. We treated 22 patients with sclerosing pancreatitis, and identified and followed-up three with concomitant hydronephrosis caused by ureteral mass, later diagnosed as retroperitoneal fibrosis. We histologically examined the ureteral and pancreatic lesions of these patients and noted abundant infiltration of IgG4-bearing plasma cells in both tissues. Treatment with corticosteroids lowered serum concentrations of IgG4. IgG4 might also have a pathological role in a systemic fibrosing process that includes pancreatic and retroperitoneal lesions.

Jaundice caused by a pancreatic mass: an exceptional presentation of Crohn's disease

It is well known that Crohn's disease can involve the pancreas. However, granulomatous inflammation of the pancreas causing jaundice is extremely rare. In this report, we describe a patient presenting with jaundice in whom a Whipple procedure was performed because of the suspicion of a malignant pancreatic tumor. However, on histologic examination a benign granulomatous pancreatic mass was found. Further investigations revealed no other organ involvement and no underlying disease could be identified. Therefore, the tentative diagnosis of an idiopathic inflammatory pseudotumor was made. Only 6 months later, when the patient developed bloody diarrhea, Crohn's disease was diagnosed. This case stresses that, especially in young patients, Crohn's disease should be included in the differential diagnosis of benign common bile duct strictures even if no other symptoms of Crohn's disease are present.

CT appearance of gastric involvement in multifocal idiopathic fibrosclerosis

Multifocal idiopathic fibrosclerosis (also called multifocal fibrosclerosis) is an uncommon disease in which there is a systemic overgrowth of fibrous tissues, with a spectrum of aggressiveness ranging from benign retroperitoneal fibrosis to pachymeningitis. We describe the first case of gastric involvement of multifocal fibrosclerosis and its appearance on CT.

Peritoneal sclerosis: one or two nosological entities?

The frequency, pathology, animal models, pathogenesis, clinical manifestations, diagnostic criteria, therapy and prevention of peritoneal sclerosis are reviewed. Many of these aspects have a bimodal configuration which suggests that peritoneal sclerosis, usually considered a single pathology in peritoneal dialysis, is actually two distinct nosological entities: simple sclerosis and sclerosing peritonitis. The former is very frequent, with minor anatomical alterations and low clinical impact; it is reproducible in animals by means of peritoneal dialysis, and is clearly due to the poor biocompatibility of peritoneal dialysis solutions. The latter is rare, with radical anatomical alterations and high mortality requiring valid methods of diagnosis, therapy and prevention; it can only be reproduced in animal models by means other than peritoneal dialysis and seems to be due to factors both related and unrelated to peritoneal dialysis.