Comparing faecal Elastase-1 and ¹³C mixed triglyceride breath test in patients undergoing pancreatic surgery

The optimal test for diagnosing pancreatic exocrine insufficiency (PEI) remains debated. This study compares the diagnostic accuracy of faecal elastase-1 (FE-1) and the ¹³C Mixed Triglyceride Breath Test (MTGT) in patients undergoing pancreatic surgery.

Patients undergoing pancreatic resection at Antwerp University Hospital (2016-2023) had FE-1 and MTGT testing before and after surgery. The MTGT was used as the reference standard. Agreement between both tests was evaluated using Cohen's kappa.

Preoperatively, in a patient cohort of 249 patients, PEI was detected in 25.3 % using MTGT and 39.6 % using FE-1 (cutoff <200 μg/g). The sensitivity and specificity of FE-1 were 63.5 % and 68.3 %, respectively. Agreement was fair (κ = 0.27). After pancreatoduodenectomy, the prevalence of PEI increased to 60 % (MTGT) and 92.2 % (FE-1), with only slight agreement between tests (κ = 0.17). Although FE-1 demonstrated high sensitivity (98.1 %), its specificity was poor (16.7 %), resulting in an 83.5 % false-positive rate.

In patients undergoing pancreatic surgery, especially after pancreatoduodenectomy, the agreement between MTGT and FE-1 is substantially lower than expected. FE-1 demostrates low specificity and a high false-positive rate, resulting in overdiagnosis and unnecessary economic and patient burden.