Differential Diagnosis for Chronic Pancreatitis with Normal MRCP

Given the findings of old chronic pancreatitis on CECT abdomen and a normal MRCP, the differential diagnoses can be categorized as follows:

• Single Most Likely Diagnosis

  • Chronic pancreatitis: This is the most straightforward diagnosis given the CECT findings. The normal MRCP suggests that there are no significant ductal abnormalities that would require intervention, supporting the diagnosis of chronic pancreatitis without needing to consider other obstructive causes.

• Other Likely Diagnoses

  • Pancreatic divisum: Although MRCP is normal, some cases of pancreatic divisum might not show obvious ductal anomalies. This condition can lead to chronic pancreatitis, especially if there's inadequate drainage of pancreatic secretions.
  • Autoimmune pancreatitis: This condition can present with chronic pancreatitis-like symptoms and imaging findings. A normal MRCP does not rule out autoimmune pancreatitis, as the disease can cause diffuse or focal enlargement of the pancreas without significant ductal dilatation.
  • Groove pancreatitis: A rare form of chronic pancreatitis involving the pancreaticoduodenal groove, which might not always show significant abnormalities on MRCP.

• Do Not Miss Diagnoses

  • Pancreatic cancer: Although less likely with a normal MRCP, pancreatic cancer can sometimes present with chronic pancreatitis-like changes, especially in the background of chronic inflammation. It's crucial to follow up and ensure no new masses or lesions develop.
  • Intraductal papillary mucinous neoplasm (IPMN): These tumors can cause chronic pancreatitis and might not always be visible on MRCP, especially if they are small or do not cause significant ductal dilatation.

• Rare Diagnoses

  • Congenital anomalies of the pancreas (e.g., pancreas divisum with anomalous ducts): While some congenital anomalies might be visible on MRCP, others might not, and could potentially lead to chronic pancreatitis.
  • Eosinophilic pancreatitis: A rare condition characterized by eosinophilic infiltration of the pancreas, which can mimic chronic pancreatitis on imaging.
  • Parasitic infections (e.g., ascaris, hydatid disease): In endemic areas, parasitic infections can cause pancreatic inflammation and mimic chronic pancreatitis.