The diagnostic and prognostic value of alkaline phosphatase activity in serum and peritoneal fluid from horses with acute colic.

The research article discusses a study done to examine how levels of the enzyme alkaline phosphatase (ALP) in the blood and peritoneal fluid of horses with colic can indicate the type of intestinal damage and help predict the horse’s prognosis. It was found that elevated levels of ALP in the peritoneal fluid were associated with greater intestinal damage and a worse prognosis, indicating its potential as a biomarker for serious conditions like strangulation, peritonitis, and intestinal rupture.

Research Objective and Methodology

• This study aimed to explore the potential diagnostic and prognostic value of the enzyme ALP; specifically, the total ALP (ALPt) activity and the intestine-derived ALP (ALPi) in the serum (blood) and peritoneal fluid (fluid within the abdomen) of horses that are suffering from colic.
• The research involved testing these substances in both serum and peritoneal fluid from 126 horses with colic symptoms.
• The ALPt and ALPi activities were measured using standard and L-phenylalanine-based buffers, respectively, to determine whether different measurement methods affected the results.

Results of the Study

• Neither ALPt nor ALPi activity in the blood or peritoneal fluid was useful in classifying the type or severity of intestinal damage.
• However, the researchers found that ALPt and ALPi activities in the peritoneal fluid varied depending on the type of colic condition. Peritoneal fluid ALPt and ALPi levels were lowest in horses with simple medical colic and non-strangulated surgical lesions, medium in horses with suspected ulceration and strangulation, and highest in cases with peritonitis or intestinal rupture.
• Higher ALPt and ALPi activities in the peritoneal fluid were associated with greater intestinal damage, an increased likelihood of the need for surgery, and a worse prognosis.

Conclusion and Implications

• The study concluded that measuring total ALP activity in peritoneal fluid may assist in identifying ischemic or inflammatory bowel lesions in horses with acute colic.
• However, the use of L-phenylalanine buffer, as opposed to a standard buffer, in both serum and peritoneal fluid did not improve the sensitivity of the test.
• The results of this study suggest that while ALP activity does not help identify the type or severity of intestinal damage, it could serve as an important biomarker for diagnosis and prognosis in horses with certain types of colic, particularly those with more severe conditions.