Idiopathic Duct Centric Pancreatitis (Autoimmune Type 2)
Differential Diagnosis
| Lymphoplasmacytic Sclerosing Pancreatitis (Autoimmune Type 1) |
Idiopathic Duct Centric Pancreatitis (Autoimmune Type 2) |
| No neutrophilic invasion and destruction of ductal epithelium |
Neutrophilic invasion and destruction of ductal epithelium |
| Prominent sclerosis |
Less prominent sclerosis |
| Frequent obliterative venulitis |
Lacks obliterative venous damage |
| IgG4 plasma cells >20-50/HPF |
IgG4 plasma cells infrequent (<10/HPF) |
| Serum IgG4 usually elevated |
Serum IgG4 rarely elevated |
| Frequently associated with extrapancreatic inflammatory lesions |
Associated only with inflammatory bowel disease |
| Responds to steroids but frequently relapses |
Responds to steroids but rarely relapses |
| Rare under age 50 |
Average age 50 |
More of a gross problem than a microscopic problem
| Idiopathic Duct Centric Pancreatitis (Autoimmune Type 2) |
Chronic Pancreatitis, NOS |
| Overall pattern is mass lesion composed of lymphocytes and plasma cells, no duct dilation |
Overall pattern is acinar atrophy with dilated ducts |
| Both chronic and acute infiltrate centered on ducts |
Lacks substantial focused infiltrate |
| Idiopathic Duct Centric Pancreatitis (Autoimmune Type 2) |
Alcoholic Pancreatitis |
| Overall pattern is mass lesion composed of lymphocytes and plasma cells, no duct dilation |
Pattern is basically atrophic with duct dilation |
| Stones, fat necrosis and pseudocysts not seen |
Stones, fat necrosis and pseudocysts common |
