What diagnostic tests should be ordered for a 41-year-old patient with a history of Rheumatoid Arthritis (RA) presenting with pancreatitis, without a history of smoking or alcohol consumption, and normal Liver Function Tests (LFTs)?

From the Guidelines

For a 41-year-old with rheumatoid arthritis who has developed pancreatitis without typical risk factors like alcohol or smoking and has normal liver function tests, I recommend ordering serum triglyceride levels, calcium levels, and a medication review focusing on RA treatments, as well as an abdominal ultrasound or MRI/MRCP to evaluate for gallstones, pancreatic structural abnormalities, or autoimmune pancreatitis. This approach is supported by the most recent guidelines, including the 2022 AGA clinical practice update on the endoscopic approach to recurrent acute and chronic pancreatitis, which suggests that endoscopic ultrasound is the preferred diagnostic test for unexplained acute and recurrent pancreatitis 1. Given the patient's age and the absence of typical risk factors, it is crucial to consider less common causes of pancreatitis, such as drug-induced pancreatitis from RA medications like methotrexate, azathioprine, and sulfasalazine, as well as autoimmune pancreatitis associated with RA. The initial evaluation should include:

• Serum triglyceride levels to rule out hypertriglyceridemia as a cause of pancreatitis
• Calcium levels to check for hypercalcemia
• Medication review to assess the potential role of RA treatments in causing pancreatitis
• Abdominal ultrasound or MRI/MRCP to evaluate for gallstones, pancreatic structural abnormalities, or autoimmune pancreatitis If these initial tests are unrevealing, further investigation with endoscopic ultrasound may be warranted, as suggested by the 2022 AGA clinical practice update 1. Additionally, managing the pancreatitis with standard supportive care, including bowel rest, IV fluids, and pain management, is essential while awaiting the results of the diagnostic tests, as recommended by the 2019 WSES guidelines for the management of severe acute pancreatitis 1. It is also important to consider the patient's history of RA and the potential for shared autoimmune mechanisms or medication side effects contributing to the development of pancreatitis, as noted in the 2007 AGA institute medical position statement on acute pancreatitis 1.

From the Research

Diagnostic Approach for Acute Pancreatitis

Given the patient's history of RA and presentation with pancreatitis without smoking or alcohol use, and negative liver function tests (LFTs), the diagnostic approach should focus on identifying the cause of pancreatitis and assessing its severity.

• Serum Markers:
  • Lipase is preferred over amylase for diagnosing acute pancreatitis due to its higher sensitivity and specificity 2, 3.
  • Serum lipase offers a larger diagnostic window than amylase, making it useful in both early and late stages of acute pancreatitis 2.
• Imaging Studies:
  • Contrast-enhanced computed tomography (CECT) is useful for estimating the presence and extent of pancreatic necrosis and for identifying patients at high risk for systemic and local complications 3, 4.
  • Ultrasonography is mainly used for evaluating the biliary tract in acute pancreatitis 3.
  • Imaging guidelines recommend selective use of diagnostic imaging to minimize unnecessary studies and reduce healthcare costs 5.
• Other Considerations:
  • Serum amylase and lipase levels can be elevated in nonpancreatic conditions, leading to potential misdiagnosis 6.
  • The diagnosis of acute pancreatitis should consider clinical presentation, serum markers, and radiological evidence to increase accuracy 6.

Recommended Tests

Based on the provided evidence, the following tests are recommended for the patient:

• Serum lipase
• Contrast-enhanced computed tomography (CECT) if clinically indicated for assessing severity or complications
• Ultrasonography if biliary obstruction is suspected as the cause of pancreatitis