Table 1.

Cardinal features for differential diagnosis

Characteristics	Drug-induced pancreatitis	Idiopatic IBD-associated pancreatitis	Autoimmune pancreatitis
Epidemiology	Pediatric patients Elderly patients Females > males	Males >> females	Male-female 2:1 (type 1) Male-female: 1:1 (type 2)
Age at presentation of pancreatitis	Any ages	20-40 yr	60-65 yr (type 1) 45-50 yr (type 2)
Clinical presentation	Abdominal pain	Abdominal pain Exocrine pancreatic insufficiency	Jaundice Mild abdominal pain Diabetes
Sierology	Elevated pancreatic enzymes Normal IgG4	Elevated pancreatic enzymes Normal IgG4	Normal or slightly elevated pancreatic enzymes Elevated IgG4 (in type 1)
Imaging	Normal pancreas or oedematous pancreatitis	Normal pancreas or oedematous pancreatitis Diffuse pancreatic enlargement or long/multiple MPD narrowing No calcifications or pseudocysts	Diffuse pancreatic enlargement or long/multiple MPD narrowing No calcifications or pseudocysts
Key point	Direct correlation between resolution of symptoms and drug withdrawal Symptoms recurrence with re-challenge test	Exclusion of other causes of pancreatitis (drug, lithiasis, alcohol...)	Rapid response to steroid with radiologically demonstrable resolution or marked clinical improvement

MPD: Main pancreatic duct; IBD: Inflammatory bowel disease.