Autoimmune pancreatitis: medical and surgical management.

CONTEXT Autoimmune pancreatitis is characterised by a lymphoplasmacytic infiltrate consisting in part of plasma cells that produce large amounts of IgG4. It can manifest as focal or diffuse enlargement of the pancreas with associated strictures of the pancreato-bilary tree giving rise to symptoms including abdominal pain, weight loss and obstructive jaundice; thus it can be extremely difficult in both presentation and investigation to distinguish from pancreatic carcinoma. Recent advances now facilitate preoperative diagnosis and effective medical management, including steroid treatment of autoimmune pancreatitis so preventing major surgical intervention. CASE REPORT Two cases of autoimmune pancreatitis are described, each of which presented with obstructive jaundice and a relatively painless pancreatic mass, one with vascular involvement. They each had elevated serum CA 19-9 and ultimately required surgical exploration to definitely exclude malignancy before embarking on non operative treatment. The first case settled spontaneously while the second rapidly improved with steroid treatment. CONCLUSION These two cases illustrate the difficulties in diagnosing this condition, the efficacy of steroid therapy and the role of surgical intervention in unresponsive cases or those where a diagnostic dilemma remains.