Autoimmune pancreatitis in an 11-year-old boy

Pediatric IgG4-related disease: a descriptive review

INTRODUCTION

IgG4-related disease (IgG4-RD) is an immune-mediated systemic fibroinflammatory condition characterized by serum IgG4 elevation and IgG4-positive plasma cell infiltration into various organs. It generally occurs in elderly males. Pediatric cases have been reported, albeit rarely, accordingly lack of recognition of such cases could delay therapeutic intervention leading to poorer outcomes.

AREAS COVERED

The present review is a descriptive review of all published case reports, cohort studies, and reviews of pediatric IgG4-RD listed in PubMed. Characteristics of pediatric IgG4-RD were clarified, including sex, organ involvement, serological and histological findings, and treatment. We assessed how many published cases met current classification and comprehensive diagnostic criteria.

EXPERT OPINION

The characteristics of pediatricIgG4-RD differed from adult IgG4-RD in terms of sex and involved organs. There was no clear male dominance in numbers of cases, and surface organ involvement such as ophthalmic diseases were more common in the pediatric IgG4-RD. Organ involvement tended to be indolent and unilateral, causing difficulty in definitively diagnosing pediatric IgG4-RD. Only about 20% of published cases met IgG4-RD classification or comprehensive diagnostic criteria. Physicians should be careful in diagnosing pediatric IgG4-RD after excluding mimickers. International collaboration toward high-quality evidence to support diagnosis and treatment of pediatric IgG4-RD is advised.

Type 2 Autoimmune Pancreatitis: Consensus and Controversies

Autoimmune pancreatitis (AIP) has attracted much attention in the last two decades, and due to the diagnostic value of immunoglobulin G4 (IgG4), the number of cases diagnosed in clinical practice has markedly increased. However, in contrast to prototypic IgG4-related type 1 AIP, a minor subtype of AIP, referred to as type 2 AIP, is less widely known and has thus not yet been characterized in detail. Type 2 AIP is unrelated to IgG4 and is a completely distinct entity from type 1 AIP. One confusing factor is that the two types of AIP share patterns of clinical presentation (e.g., acute pancreatitis and painless jaundice) and imaging abnormalities (e.g., diffuse or segmental enlargement). Since there are currently no established serum markers, the diagnosis of type 2 AIP is highly challenging and requires the tissue confirmation of neutrophilic injury to the pancreatic ducts, a finding designated as a granulocytic epithelial lesion. Approximately one-third of cases are associated with inflammatory bowel disease, particularly ulcerative colitis; however, the pathological relationship between these two conditions has not yet been clarified. Unanswered questions relate to its pathophysiology, the potential development of a similar granulocytic injury in other organs, and the characteristics of pediatric cases. This review summarizes consensus and controversies surrounding type 2 AIP, with the aim of increasing awareness and highlighting the unmet needs of this underrecognized condition.

The Challenge of Autoimmune Pancreatitis: A Portrayal From the Pediatric Perspective

Autoimmune pancreatitis (AIP) is a rare disorder characterized by prompt clinical response to corticosteroids. Lost tolerance to a variety of pancreatic antigens and subsequent development of autoantibodies are presumably involved in the initiation of AIP. Even pediatric patients have been reported with features of AIP, and awareness of this disorder is increasing among different clinicians. The terms lymphoplasmacytic sclerosing pancreatitis and idiopathic duct-centric pancreatitis refer to the different histologic patterns of AIP, named type 1 and type 2, respectively. A combination of serologic, radiologic, and histologic investigations is needed to assess diagnosis of AIP and rule out neoplastic disorders. In addition, type 1 AIP can be distinguished by raised levels of serum immunoglobulin G4 and should be considered as part of systemic immunoglobulin G4-related disease. Conversely, type 2 AIP is frequently reported in younger patients and has less clear immune-mediated pathogenetic mechanisms. The natural history of pediatric AIP is obscure, and the diagnostic usefulness of different autoimmune abnormalities found in adults with AIP is limited for children. Tips to manage pediatric patients with AIP have been recently drafted through a set of recommendation statements. This review describes the current data about AIP and the pathogenic contribution of specific autoantibodies expressly in the pediatric population.

Recommendations for Diagnosis and Management of Autoimmune Pancreatitis in Childhood: Consensus From INSPPIRE

OBJECTIVES

Autoimmune pancreatitis (AIP) represents a complex immune-mediated pancreas disorder. Pediatric AIP (P-AIP) is rare. We have recently summarized the characteristic features of P-AIP. We now aim to develop recommendation statements to standardize the diagnostic and therapeutic approach to P-AIP and facilitate future research in the field.

METHODS

A panel of pediatric gastroenterologists participating in the International Study Group of Pediatric Pancreatitis: In search for a cuRE was formed to discuss and then vote on 15 recommendation statements. A consensus of at least 80% was obtained following 3 voting rounds and revision of the statements.

RESULTS

We have now generated 15 statements to help standardize the approach to diagnosis and management of P-AIP.

CONCLUSIONS

The first P-AIP recommendation statements developed by the International Study Group of Pediatric Pancreatitis: In search for a cuRE group are intended to bring standardization to the diagnosis and treatment of this rare childhood disorder. These statements may help guide a uniform approach to patient care and facilitate future research studies.

Autoimmune Pancreatitis in Children: Characteristic Features, Diagnosis, and Management

OBJECTIVES

Autoimmune pancreatitis (AIP) is an increasingly recognized disease entity, but data in children are limited. AIP presentation and outcome in children might differ from the adult experience. We aim to determine the characteristic features of AIP in children.

METHODS

Data about clinical symptoms, imaging, histology, and treatment were collected using two sources: (i) a systematic literature search and (ii) the INSPPIRE database, the largest international multicenter study of pancreatitis in children and the Cliniques Universitaires St-Luc (CUSL) registry.

RESULTS

We identified 48 AIP cases: 30 from literature review, 14 from INSPPIRE, and 4 from CUSL. The median age at diagnosis was 13 years (range 2-17 years). Abdominal pain (43/47, 91%) and/or obstructive jaundice (20/47, 42%) were the most common symptoms at diagnosis. Elevated serum IgG4 levels were only observed in 9/40 (22%) children. Cross-sectional imaging studies were abnormal in all children including hypointense global or focal gland enlargement (39/47, 83%), main pancreatic duct irregularity (30/47, 64%), and common bile duct stricture (26/47, 55%). A combination of lymphoplasmacytic inflammation, pancreatic fibrosis, and ductal granulocyte infiltration were the main histological findings (18/25, 72%). Children with AIP had a prompt clinical response to steroids. Complications of AIP included failure of exocrine (4/25, 16%) and endocrine (3/27, 11%) pancreas function.

CONCLUSIONS

Pediatric AIP has a distinct presentation with features similar to type 2 AIP in adults. This comprehensive report on the largest group of children with AIP to date is expected to help with the diagnosis and management of this disease and pave the way for future research studies.

Type 2 autoimmune pancreatitis: case report of a 9-year-old female and a review of the literature

We report a case of autoimmune pancreatitis in a 9-year-old female who presented with persistent epigastric pain for 3 weeks. Magnetic resonance cholangiopancreatography (MRCP) showed both intrahepatic and extrahepatic biliary ductal dilatation. The common bile duct, along with the pancreatic duct, was noted to be dilated. Labs showed normal IgG and IgG4 levels and negative for autoimmune antibodies. Endoscopic ultrasound revealed the pancreatic head to be enlarged and surrounded by hypoechoic and lobulated lymph nodes. Biopsy of the pancreatic head showed chronic mildly active inflammation with fibrosis, acinar atrophy, and lymphocytic infiltrate. A diagnosis of autoimmune pancreatitis (AIP) was made, and she was treated with prednisone. The patient's symptoms improved quickly, and follow-up MRCP showed resolution of inflammatory changes and intrahepatic and pancreatic ductal dilatation.

Etiology, pathology, management and prognosis of chronic pancreatitis in Chinese population: A retrospective study

The purpose of this study was to investigate the etiology, pathological characteristics, management and prognosis of chronic pancreatitis in the Chinese population. The clinical data of 142 patients with chronic pancreatitis were retrospectively studied. All patients were of Chinese nationality and hospitalized from January 2008 to December 2011. Their ages ranged from 14 to 76 years, with a mean of 43 years. Of 142 patients, there were 72 cases of obstructive chronic pancreatitis (50.70%), 19 cases of alcoholic chronic pancreatitis (13.38%), 14 cases of autoimmune pancreatitis (9.86%) and 37 cases of undetermined etiology (26.06%). Pathologically, the average inflammatory mass diameter was 3.8 ± 3.3 cm, biliary obstruction occurred in 36 cases, gall stones in 70 cases, calcification in 88 cases, ductal dilatation in 61 cases, side branch dilatation in 32 cases, ductal irregularity in 10 cases, lymphocytic inflammation in 23 cases, obliterative phlebitis in 14 cases, extra pancreatic lesion in 19 cases and fibrosis in 142 cases. Location of pancreatic lesion in the region of head (n=97), neck (n=16), body (n=12), tail (n=15) and whole pancreas (n=2) influenced the choice of surgical procedures. Ninety-four patients (66.20%) received surgical treatment and 33.80% received other treatments. After operation, 80.85% of 94 patients experienced decreased pain, and 8.51% of 94 showed recovery of endocrine function but with a complication rate of 12.77%. All the operations were performed successfully. According to the pain scale of European Organization for Research and Treatment of Cancer (QLQ-C30) a decrease from 76 ± 22 to 14 ± 18 was observed. Etiology, pathological characteristics, management and prognosis of chronic pancreatitis in the Chinese population vary from others.

Retrospective study of steroid therapy for patients with autoimmune pancreatitis in a Chinese population

AIM: To explore the optimal steroid therapeutic strategy for autoimmune pancreatitis (AIP).

METHODS: This study was conducted retrospectively in two large institutions in China. Patients with clinically, radiologically and biochemically diagnosed AIP were enrolled. The performed radiological investigations and biochemical tests, the regimen of the given steroid treatment, remission and relapse whether with and without steroid therapy were analyzed.

RESULTS: Twenty-eight patients with AIP received steroid treatment, while 40 patients were treated surgically by pancreatoduodenectomy, distal pancreatectomy and choledochojejunostomy, radiofrequency ablation for the enlarged pancreatic head, percutaneous transhepatic biliary drainage and endoscopic biliary drainage. The starting oral prednisolone dose was 30 mg/d in 18 (64.3%) patients and 40 mg/d in 10 (35.7%) patients administered for 3 wk. The remission rate of AIP patients with steroid treatment (96.4%) was significantly higher than in those without steroid treatment (75%). Maintenance therapy (oral prednisolone dose 5 mg/d) was performed after remission for at least 6-12 mo to complete the treatment course. Similarly, the relapse rate was significantly lower in AIP patients with steroid treatment (28.6%) than in those without steroid treatment (42.5%). Steroid re-treatment was effective in all relapsed patients with or without steroid therapy.

CONCLUSION: Steroid therapy should be considered in all patients with active inflammatory phase of AIP. However, the optimal regimen still should be trailed in larger numbers of patients with AIP.

Diagnosis of autoimmune pancreatitis vs neoplasms in children with pancreatic mass and biliary obstruction

Autoimmune pancreatitis (AIP) is a rare autoimmune disorder that resembles pancreatic neoplasia and occurs primarily in adults. Management strategies and diagnostic criteria are being revised for adult patients; there are no clear diagnostic criteria for pediatric patients. We describe 3 cases of AIP in children, on the basis of clinical and pathology records. We also performed a literature review to determine the incidence of biliary obstruction in pediatric patients with pancreatic tumors. We found that children with AIP present with a variety of symptoms, and that diagnostic and therapeutic strategies also vary. Furthermore, on the basis of the many studies published on pediatric patients with pancreatic tumors, only a small percentage of the patients have biliary obstructions. Cytologic analysis of samples collected by fine-needle aspiration cytology does not accurately identify AIP in children. However, frozen section needle core biopsy samples can be used to distinguish children with AIP from those with neoplasia. Children with pancreatic mass and biliary obstruction are more likely to have AIP than neoplasms.

Histopathologically proven autoimmune pancreatitis mimicking neuroendocrine tumor or pancreatic cancer

Autoimmune pancreatitis (AIP) can be difficult to distinguish from pancreatic cancer. We report a case of histopathologically proven AIP mimicking neuroendocrine tumor (NET) or pancreatic cancer in a 53-year-old man. He was referred to our hospital for further evaluation of a pancreatic mass detected on ultrasonography at a medical check-up. Abdominal ultrasonography showed a 15-mm hypoechoic mass located in the pancreatic body. Computed tomography revealed a tumor without any contrast enhancement, and magnetic resonance imaging demonstrated the mass to be hyperintense on diffusion-weighted image. Endoscopic retrograde cholangiopancreatography revealed slight dilatation of a branch of the pancreatic duct without stricture of the main pancreatic duct. The common bile duct seemed intact. Under suspicion of a non-functioning NET or malignant neoplasm, laparotomy was performed. At laparotomy, an elastic firm and well-circumscribed mass was found suggestive of a non-functioning NET, thus enucleation was performed. Histopathologically, the lesion corresponded to AIP.

Successful treatment of pediatric IgG4 related systemic disease with mycophenolate mofetil: case report and a review of the pediatric autoimmune pancreatitis literature

Autoimmune pancreatitis is frequently associated with elevated serum and tissue IgG4 levels in the adult population, but there are few reports of pediatric autoimmune pancreatitis, and even fewer reports of IgG4 related systemic disease in a pediatric population. The standard of care treatment in adults is systemic corticosteroids with resolution of symptoms in most cases; however, multiple courses of corticosteroids are occasionally required and some patients require long term corticosteroids. In these instances, steroid sparing disease modify treatments are in demand. We describe a 13-year-old girl with IgG4 related systemic disease who presented with chronic recurrent autoimmune pancreatitis resulting in surgical intervention for obstructive hyperbilirubinemia and chronic corticosteroid treatment. In addition, she developed fibrosing medianstinitis as part of her IgG4 related systemic disease. She was eventually successfully treated with mycophenolate mofetil allowing for discontinuation of corticosteroids. This is the first reported use of mycophenolate mofetil for IgG4 related pancreatitis. Although autoimmune pancreatitis as part of IgG4 related systemic disease is rarely reported in pediatrics, autoimmune pancreatitis is also characterized as idiopathic fibrosing pancreatitis. All pediatric autoimmune pancreatitis cases reported in the world medical literature were identified via a PUBMED search and are reviewed herein. Twelve reports of pediatric autoimmune pancreatitis were identified, most of which were treated with corticosteroids or surgical approaches. Most case reports failed to report IgG4 levels, so it remains unclear how commonly IgG4 related autoimmune pancreatitis occurs during childhood. Increased evaluation of IgG4 levels in patients with autoimmune pancreatitis may shed further light on the association of IgG4 with pancreatitis and the underlying pathophysiology.

Successful treatment of pediatric IgG4 related systemic disease with mycophenolate mofetil: case report and a review of the pediatric autoimmune pancreatitis literature

Autoimmune pancreatitis is frequently associated with elevated serum and tissue IgG4 levels in the adult population, but there are few reports of pediatric autoimmune pancreatitis, and even fewer reports of IgG4 related systemic disease in a pediatric population. The standard of care treatment in adults is systemic corticosteroids with resolution of symptoms in most cases; however, multiple courses of corticosteroids are occasionally required and some patients require long term corticosteroids. In these instances, steroid sparing disease modify treatments are in demand. We describe a 13-year-old girl with IgG4 related systemic disease who presented with chronic recurrent autoimmune pancreatitis resulting in surgical intervention for obstructive hyperbilirubinemia and chronic corticosteroid treatment. In addition, she developed fibrosing medianstinitis as part of her IgG4 related systemic disease. She was eventually successfully treated with mycophenolate mofetil allowing for discontinuation of corticosteroids. This is the first reported use of mycophenolate mofetil for IgG4 related pancreatitis. Although autoimmune pancreatitis as part of IgG4 related systemic disease is rarely reported in pediatrics, autoimmune pancreatitis is also characterized as idiopathic fibrosing pancreatitis. All pediatric autoimmune pancreatitis cases reported in the world medical literature were identified via a PUBMED search and are reviewed herein. Twelve reports of pediatric autoimmune pancreatitis were identified, most of which were treated with corticosteroids or surgical approaches. Most case reports failed to report IgG4 levels, so it remains unclear how commonly IgG4 related autoimmune pancreatitis occurs during childhood. Increased evaluation of IgG4 levels in patients with autoimmune pancreatitis may shed further light on the association of IgG4 with pancreatitis and the underlying pathophysiology.

Autoimmune pancreatitis with atypical imaging findings that mimicked an endocrine tumor

Autoimmune pancreatitis (AIP) is a rare cause of recurrent acute pancreatitis or chronic pancreatitis in middle-aged patients, and is characterised by a marked infiltration of lymphocytes and plasma cells in pancreatic tissue. Diagnosis of focal forms can be difficult as AIP may mimic pancreatic adenocarcinoma. Pediatric cases of AIP are exceptional. We report the case of a 15-year-old girl who had a focal AIP and associated cholangitis, with a very unusual vascularized mass that mimicked a pancreatic endocrine tumor. The diagnosis was obtained by a pancreatic biopsy, thus avoiding surgical resection, and all the clinical, biological and radiological abnormalities resolved after steroid therapy with 6 mo of follow-up.

Relapsing autoimmune pancreatitis in a 14-year-old girl

We present a case of acute pancreatitis in a 14-year-old girl which fulfilled the diagnostic criteria of autoimmune pancreatitis (AIP) and responded to corticosteroid therapy. Imaging studies revealed that the main pancreatic duct was narrow in the head of the pancreas but had been dilated in the body at an earlier stage. The pancreatitis recurred twice when the prednisolone dose was reduced to 10 mg or less but responded each time to an increased dose and has been kept under control with low-dose prednisolone therapy for 3 years since onset. Repeated magnetic resonance cholangiopancreatography during steroid therapy revealed an improvement of the narrowing of the main pancreatic duct in the head and dilation of the duct in the body. AIP in younger patients has distinct clinical features, such as presentation with epigastralgia, back pain without jaundice, and elevated serum amylase levels. The serum level of IgG4 is rarely increased in young patients, indicating a different disease mechanism than for cases in elderly patients. Given the excellent response of this condition to steroid therapy, AIP should be considered even in young children and adolescents when the diagnosis of idiopathic pancreatitis is suggested.