Pediatric Autoimmune Pancreatitis

Objectives Autoimmune pancreatitis (AIP) is a rare form of a chronic, immune-mediated, inflammatory pancreatic condition. There is limited data regarding presentation and outcome in the pediatric population. We described a single-center case series of 4 pediatric patients with AIP to better understand the presentation, symptoms, and outcomes of this rare condition. Methods Data collected included demographics, serology markers, symptoms at presentation, imaging, additional organ involvement, histology, treatment methods, and outcomes. The diagnosis of AIP was made by a combination of serology, pancreatic imaging, histology, extrapancreatic manifestations, and steroid response. Results All patients were diagnosed with type 2 AIP. Abdominal pain, emesis, and obstructive jaundice were the most common symptoms at presentation. Autoimmune markers were negative. Cross-sectional abdominal imaging showed diffuse/focal pancreatic gland enlargement and common bile duct stricture universally and main pancreatic duct irregularity in half of the patients. Biopsies showed lymphoplasmacytic infiltration with associated pancreatic fibrosis and atrophy. Treatment with an 8-week tapering course of prednisone showed prompt response with resolution of symptoms and normalization of laboratory test results. Conclusions Our case series shows that AIP in children is a rare entity with a distinct clinical presentation, classical radiographic and histological features with good long-term prognosis.