A functional turbidimetric method to determine C-reactive protein in horses.

The study presents a turbidimetric method, based on soybean oil-phosphocholine interaction, for determining the concentration of C-reactive protein (CRP) in horse serum samples. It evaluates the potential of this method in veterinary diagnostic applications and compares it with other inflammatory markers.

Research Methodology

• The research involved the application of a turbidimetric method which relies on the interaction between soybean oil and phosphocholine to detect C-reactive protein (CRP) in horse serum.
• A preparation of ‘Intralipid 20%’ in a Tris-calcium buffer of pH 7.5 was added to the horse serum, then incubated for 30 minutes at 37 °C.
• The formed CRP-phosphocholine complexes were then counted bichromatically (at both 660 nm and 700 nm) using a commercial analyzer.

Comparative Evaluation

• The researchers evaluated the effectiveness of the CRP measurement as an inflammatory marker in comparison with other common markers – white blood cell count and neutrophil count.

Standardization and Application

• A standardization process was performed using a commercial human CRP calibrator and measurements were made on 296 patient serum samples and 34 controls.
• Reference values for CRP were found to be less than 10 mg/l.
• The study found that the CRP measurement method was valid for a range of 1 to 400 mg/l.

Results and Implications

• The findings showed a moderate correlation between the CRP and relative neutrophil counts.
• A receiver-operating characteristics (ROC) analysis determined the area-under-the-curve value for CRP was 0.928, which was significantly better than the neutrophil count (0.804) and leucocyte count (0.664) in detecting inflammation.
• These results suggest that the CRP assay used in the study shows reliable outcomes as an acute phase test in horses, meaning it can accurately act as an inflammation monitor.