Diagnostic features and differential diagnosis of autoimmune pancreatitis
Section snippets
Clinical features
AIP is slightly more common in males (M/F = 2/1) despite the well known propensity of autoimmune conditions to occur in females. The patients seem to cluster into two clinico-pathologically distinct subsets.13 One type occurs predominantly in older men (mean age, mid-60s), is often associated with Sjögren syndrome, bile-duct stenosis, and morphologically exhibits the classical lymphoplasmacytic sclerotic pattern of “AIP.” The second is seen in younger patients (mean age, early 40s), show an
Pathologic characteristics
AIP is characterized by fibrosis and inflammation of pancreatic tissue, which typically manifests as enlargement of the pancreatic head, and constriction of the common bile duct. In a small percentage of cases, the lesion occurs in the tail, may involve the peripancreatic adipose tissue and cause adhesions to the surrounding organs including the colon or spleen. Diffuse involvement of pancreas may also occur but is uncommon.5, 9
Additional studies
Simple histochemical stains may help confirm the vascular involvement by the inflammatory process. Special stains that highlight the components of the vessels such as EVG or movat pentichrome,62 or in some cases, muscular or endothelial markers, may help confirm the presence of periphlebitis.
Immunohistochemical stain for IgG4 is becoming a very helpful adjunct for the diagnosis of AIP, not only in resection specimens, but also in biopsies.44, 63, 64, 65 Recent studies indicate that in many
Differential diagnosis
It is important to distinguish AIP from the other types of pancreatitis, in particular, alcoholic, because the management and prognosis are vastly different. This differential is challenging both at the clinical and pathologic levels, and the correlation of clinical and pathologic findings may be necessary. As discussed previously, lack of alcohol history has been advocated as one of the defining criteria for AIP. The morphologic findings are also helpful in this distinction.
Ductal dilation,
Fine needle aspiration biopsy
Patients with AIP often undergo fine-needle aspiration biopsy with the preoperative diagnosis of carcinoma. The presence of stromal fragments with lymphocytes greater than 30 per 60× has been found to be in favor of AIP,81 although it is by no means specific. Also, the stromal fragments are significantly more cellular in AIP cases.5, 81, 82, 83, 84 If these findings are evaluated in conjunction with the clinical and radiologic findings, they may help achieve the correct diagnosis, or at least
Management and outcome
Until recently, most AIPs have been resected due to the preoperative misdiagnosis of adenocarcinoma. This is still true for most patients. Following surgery, some patients experienced emergence of new foci of strictures or pseudotumors.16, 47, 48 There is overwhelming evidence in the literature that AIP is highly responsive to steroid therapy.25, 85, 86, 87, 88, 89, 90, 91 It is expected that as the clinical and pathologic criteria for the diagnosis of AIP are better defined it will become
References (91)
- et al.
Lymphoplasmacytic sclerosing pancreatitis with cholangitisa variant of primary sclerosing cholangitis extensively involving pancreas
Hum Pathol
(1991) - et al.
Clinical difficulties in the differentiation of autoimmune pancreatitis and pancreatic carcinoma
Am J Gastroenterol
(2003) - et al.
EUS findings in patients with autoimmune pancreatitis
Gastrointest Endosc
(2004) - et al.
Chronic pancreatitis, sclerosing cholangitis, and sicca complex in two siblings
Lancet
(1975) - et al.
Chronic pancreatitis and inflammatory bowel disease
Clin Radiol
(1979) - et al.
Sclerosing cholangitis, chronic pancreatitis, and Sjogren’s syndromea syndrome complex
Am J Surg
(1984) - et al.
Serum antibodies to carbonic anhydrase I and II in patients with idiopathic chronic pancreatitis and Sjogren’s syndrome
Gastroenterology
(1996) - et al.
Chronic pancreatitis and inflammatory bowel diseasetrue or coincidental association
Am J Gastroenterol
(1999) - et al.
Diffuse pancreatic fibrosisan uncommon feature of multifocal idiopathic fibrosclerosis
Am J Gastroenterol
(1998) - et al.
Hepatic hilar inflammatory pseudotumor mimicking cholangiocarcinoma with cholangitis and phlebitis–a variant of primary sclerosing cholangitis?
Pathol Res Pract
(1997)
Idiopathic retroperitoneal fibrosis producing common bile duct and pancreatic duct obstruction
Gastroenterology
Localized lymphoplasmacellular pancreatitis forming a pancreatic inflammatory pseudotumor
Mayo Clinic Proceedings
Acute pancreatitis
Semin Diagn Pathol
Relapsing pancreatitis associated with duodenal wall cystsdiagnostic approach and treatment
Gastroenterology
Paraduodenal pancreatitisa clinico-pathologically distinct entity unifying “cystic dystrophy of heterotopic pancreas,” “para-duodenal wall cyst” and “groove pancreatitis”
Semin Diag Pathol
Autoimmune pancreatitispossibilities of CT characterization
Pancreatology
Lymphoplasmacytic sclerosing (autoimmune) pancreatitis
Semin Diagn Pathol
Comparison of endoscopic ultrasound-guided fine needle aspiration for focal pancreatic lesions in patients with normal parenchyma and chronic pancreatitis
Am J Gastroenterol
ERCP features in 27 patients with autoimmune pancreatitis
Gastrointest Endosc
A case of autoimmune pancreatitis responding to steroid theraphy:evidence of histologic recovery
Pancreatology
Sclerosing pancreato-cholangitis responsive to steroid theraphy
Lancet
Chronic pancreatitis caused by an autoimmune abnormalityproposal of the concept of autoimmune pancreatitis
Dig Dis Sci
Autoimmune pancreatitis as a new clinical entitythree cases of autoimmune pancreatitis with effective steroid therapy
Dig Dis Sci
Autoimmune pancreatitispathological, clinical, and immunological features
Pancreas
Histopathological features of diagnostic and clinical relevance in autoimmune pancreatitisa study on 53 resection specimens and 9 biopsy specimens
Virchows Arch
Chronic inflammatory sclerosis of the pancreas–an autonomous pancreatic disease?
Am J Dig Dis
Autoimmune-related pancreatitis
Curr Treat Options Gastroenterol
Duct destructive chronic pancreatitisa new insight into the pathology of idiopathic non-alcoholic chronic pancreatitis
Gut
Non-alcoholic duct destructive chronic pancreatitis
Gut
Non-alcoholic duct-destructive chronic pancreatitisrecognition before definitive treatment
Yonsei Med J
Controversies in clinical pancreatology: autoimmune pancreatitis: does it exist?
Pancreas
The characteristic appearance of non-alcoholic duct destructive chronic pancreatitisa report of 2 cases
Arch Pathol Lab Med
Idiopathic chronic pancreatitis with periductal lymphoplasmacytic infiltrationclinicopathologic features of 35 cases
Am J Surg Pathol
Autoimmunity and chronic pancreatitisa concealed relationship
Jop
Lymphoplasmacytic sclerosing pancreatitisinflammatory mimic of pancreatic carcinoma
J Gastrointest Surg
Pathology of acute and chronic pancreatitis
Pancreas
Lymphoplasmacytic chronic cholecystitis and biliary tract disease in patients with lymphoplasmacytic sclerosing pancreatitis
Am J Surg Pathol
IgG4 as a serological marker of autoimmune pancreatitisthe latest news
Jop
Autoimmune pancreatitisradiologic findings in three histologically proven cases
J Comp Assist Tomogr
MRI of groove pancreatitis
J Comp Assist Tomogr
Nonalcoholic duct-destructive chronic pancreatitisimaging findings
AJR Am J Roentgenol
Autoimmune pancreatitisimaging features
Radiology
High serum IgG4 concentrations in patients with sclerosing pancreatitis
N Engl J Med
Pancreatic ductal morphology and function in primary Sjogren’s syndrome
Int J Pancreatol
Chronic sclerosing pancreatitis in Sjogren’s syndromea case report
Pancreas
Cited by (30)
Diseases of the Gallbladder
2023, MacSween's Pathology of the Liver, Eighth EditionPrimary cutaneous Rosai-Dorfman disease; a case-based review of a diagnostically and therapeutically challenging rare variant
2020, Annals of Diagnostic PathologyDiseases of the Gallbladder
2018, MacSween's Pathology of the LiverNon-neoplastic pancreatic lesions that may mimic malignancy
2016, Seminars in Diagnostic PathologyCitation Excerpt :The two types of chronic pancreatitis notorious for causing mass-like lesions, which are difficult to distinguish from carcinoma are autoimmune pancreatitis (AIP) and paraduodenal pancreatitis.2,5 AIP has been referred to as lymphoplasmacytic sclerosing pancreatitis, non-alcoholic duct-centric or duct-destructive chronic pancreatitis, sclerosing pancreatitis, and primary sclerosing cholangitis of the pancreas.2,5,6 AIP typically results in a mass or “pseudotumor” focused within the head of the pancreas.2,5,6
Follicular pancreatitis, report of a case clinically mimicking pancreatic cancer and literature review
2014, Pathology Research and PracticeInflammatory, Infectious, and Other Non-Neoplastic Disorders of the Pancreas
2009, Surgical Pathology of the GI Tract, Liver, Biliary Tract and Pancreas