Activity of 1,2-o-dilauryl-rac-glycero-3-glutaric acid-(6′-methylresorufin) ester lipase in peritoneal fluid may be associated with strangulating lesions, pancreatic fibrosis, and negative outcome in horses with colic.

Overview

• This study investigated the activity of a specific lipase enzyme (DGGR lipase) in plasma and peritoneal fluid of horses with and without colic to determine its association with pancreatic disease, strangulating lesions, and clinical outcomes.
• It also examined pancreatic tissue to identify histopathological changes such as fibrosis and autolysis in these horses.

Study Objective and Design

• The main goal was to compare DGGR lipase enzyme activity in plasma and peritoneal fluid between horses presenting with colic signs and healthy controls.
• The study aimed to correlate lipase activity with:
  • Peritoneal white blood cell (WBC) counts
  • Lactate concentrations
  • Pancreatic histopathology findings
• A prospective, cross-sectional study design was used.
• Subjects included:
  • 25 healthy university-owned or donated horses
  • 30 client-owned horses presenting for colic
  • A subset had pancreatic tissue collected post-mortem or via other means for histopathology (5 healthy and 7 colic horses)

Methods

• Measures taken:
  • 1,2-o-dilauryl-rac-glycero-3-glutaric acid-(6′-methylresorufin) ester (DGGR) lipase activity in plasma and peritoneal fluid
  • Peritoneal fluid WBC counts and lactate concentrations
  • Histopathologic grading of pancreatic tissue for fibrosis and autolysis
• DGGR lipase is a biochemical marker used to detect pancreatic lipase activity, informative of pancreatic inflammation or damage.

Key Findings

• DGGR lipase activity was:
  • Significantly higher in both plasma and peritoneal fluid of colic horses compared to healthy horses
  • Significantly correlated between plasma and peritoneal fluid in colic horses
• There was a significant relationship between increased peritoneal lactate and WBC counts with heightened plasma and peritoneal DGGR lipase activity; this suggests that lipase activity could reflect the severity of inflammation or ischemia.
• Peritoneal DGGR lipase activity was notably associated with specific clinical features:
  • Strangulating lesions in the abdomen (where blood supply to intestine is cut off)
  • Negative clinical outcomes including non-survival of the horse
• Gross pathology identified acute pancreatitis in one horse with colic, confirming that inflammation of the pancreas can accompany colic episodes.
• Histopathology revealed pancreatic fibrosis (scarring) and autolysis (self-digestion) in:
  • One healthy horse
  • Seven colic horses
• There was a correlation between pancreatic fibrosis and elevated DGGR lipase activity, suggesting that chronic pancreatic changes may influence enzyme levels.

Interpretation and Clinical Significance

• Elevated plasma and peritoneal DGGR lipase activity may serve as a biomarker for pancreatic involvement or injury in horses with colic.
• Peritoneal lipase levels, in particular, could aid in identifying horses with strangulating intestinal lesions, which often require urgent surgical intervention.
• Pancreatic fibrosis and autolysis are relatively common in colic horses and may contribute to or result from colic pathology.
• The presence of pancreatitis during colic episodes, supported by biochemical and histological data, highlights the need to consider pancreatic disease in the diagnostic evaluation of colic.
• The correlation between lipase activity and clinical outcome emphasizes the potential prognostic utility of this marker.

Conclusions and Future Directions

• Hyperlipasemia (high lipase levels) is a common finding in horses with colic and may be linked to pancreatic fibrosis and severity of disease.
• DGGR lipase activity in peritoneal fluid might be useful in assessing the presence of strangulating lesions and predicting poor outcomes.
• The findings suggest that pancreatitis, often overlooked, can occur concurrently with colic and contribute to clinical presentations.
• Further research is needed to:
  • Clarify the clinical impact of pancreatic lipase elevations in colic
  • Evaluate the diagnostic and prognostic utility of DGGR lipase measurement
  • Explore treatment strategies targeting pancreatic involvement in colic