A Study on the Activation Peptide Released from Procarboxypeptidase B (CAPAP) and Anionic Trypsinogen in Patients with Acute Abdominal Disorders of Non-pancreatic Origin

Background: The activation peptide released from procarboxypeptidase B, CAPAP, is a marker of the activation of pancreatic enzymes in acute pancreatitis while anionic trypsinogen (AT) levels in urine relate to leakage of unactivated proenzymes. Data on these markers in patients suffering from severe acute abdominal disorders of non-pancreatic origin are lacking.

Purpose: To examine levels of CAPAP and AT in serum and urine from patients with severe acute abdominal disorders of non-pancreatic origin in order to better define the diagnostic specificity of these two markers in severe acute pancreatitis in relation to other acute intra-abdominal disorders.

Subjects And Methods: The study included 54 patients with severe acute abdominal disorders of non-pancreatic origin with an APACHE II score >3. Immunoreactive CAPAP (irCAPAP) and immunoreactive AT (irAT) were measured in serum and urine using specific immunoassays.

Results: In urine, irCAPAP levels were mildly increased (>2 nmol/l) in 13% of the patients with severe acute abdominal diseases of non-pancreatic origin, but on no occasion did the increase approach the cutoff levels described for severe acute pancreatitis (>100 nmol/l). However, irAT levels in serum and urine were increased (>50 micro g/l) in 54% of the cases.

Conclusion: Contrary to what is found for irAT, patients with acute abdominal pain of non-pancreatic origin rarely have markedly increased levels of irCAPAP in serum and urine.