Non-pancreatic hyperlipasemia: A puzzling clinical entity

Area of Science:

• Gastroenterology
• Clinical Chemistry
• Internal Medicine

Background:

• Elevated lipase levels are key for diagnosing acute pancreatitis (AP), but can also indicate non-pancreatic hyperlipasemia (NPHL) due to other conditions.
• NPHL presents a diagnostic challenge, potentially leading to misdiagnosis and hindering accurate prognostication of patient outcomes.

Purpose of the Study:

• To characterize non-pancreatic hyperlipasemia (NPHL) in a large patient cohort.
• To identify clinical and laboratory factors influencing NPHL diagnosis and patient outcomes.

Main Methods:

• Prospective evaluation of 808 patients with serum lipase ≥ 3 times the upper limit of normal (ULN).
• Diagnosis of NPHL was confirmed in the absence of abdominal pain or pancreatitis-specific imaging findings.
• Analysis included assessment of demographic data, laboratory results, and in-hospital mortality.

Main Results:

• Of 808 patients, 392 had AP and 401 had NPHL with over 20 etiologies, most commonly sepsis (27.7%) and acute kidney injury (AKI) (33.2%).
• Lipase levels ≥ 666 U/L showed 71.4% sensitivity and 88.8% specificity for AP vs NPHL, but diagnostic accuracy was reduced by sepsis/AKI.
• NPHL was associated with significantly higher in-hospital mortality (22.4%) compared to AP (5.1%).

Conclusions:

• Non-pancreatic hyperlipasemia (NPHL) is a common condition associated with substantial in-hospital mortality.
• Increased neutrophil-to-lymphocyte ratio (NLR), alongside sepsis, age, and decreased albumin, are independent risk factors for mortality in NPHL.
• Sepsis and AKI complicate the differentiation of AP from NPHL based on lipase levels alone.