Magnetic resonance imaging of autoimmune pancreatitis: A review of literature [Resonancia magnética de la pancreatitis autoinmune: una revisión de la literatura]

Autoimmune pancreatitis (AIP) is a distinct form of chronic pancreatitis caused by an autoimmune pathogenetic mechanism. It affects males (60%) slightly more frequently, and generally occurs between 40 to 60 years, although the possible range is much wider (14-80 years). Histologically AIP is characterised by the presence of a dense inflammatory infiltrate, with variable extension. It can be focal or diffuse throughout the whole pancreas. Clinical presentation in most cases is non-specific, with patients presenting with mild abdominal pain, rarely, acute pancreatitis symptoms, weight loss, and jaundice. Several studies reported multiple organ involvement due to the autoimmune process, suggesting a systemic nature of the disease. In 2011 the International Consensus Diagnostic Criteria for autoimmune pancreatitis (ICDC) defined the guidelines, and magnetic resonance imaging (MRI) and MR-cholangiopancreatography (MRCP) became the reference diagnostic technique in the diagnosis of the disease. This paper will review the imaging characteristics, the differential diagnosis, and the imaging features after treatment and follow up. Furthermore, our experience in this uncommon and challenging disease is reviewed