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Published on: September 9, 2012
Evaluation of two microhematocrit methods for quantitating plasma fibrinogen
Abstract:
Blood samples from several animal species, including man, were used to compare 2 heat-precipitation assays (Millar et al and Schalm et al) with a reference assay (Ratnoff-Menzie) for quantitating plasma fibrinogen. Compared with the Ratnoff-Menzie assay, the heat-precipitation methods significantly underestimated plasma fibrinogen content. The reproducibility of the Millar et al assay was significantly better than that of the Schalm et al assay and approached that of the Ratnoff-Menzie method. The Millar et al assay, a practical test not requiring specialized equipment, is recommended for clinical use in animals.
Insights
Two heat-precipitation assays for plasma fibrinogen in animals significantly underestimated levels compared to a reference method. The Millar et al assay showed better reproducibility and is recommended for clinical use.
Area of Science:
- Veterinary Hematology
- Clinical Pathology
- Biochemistry
Background:
- Accurate quantitation of plasma fibrinogen is crucial for diagnosing and monitoring various animal diseases.
- Existing methods for plasma fibrinogen measurement vary in complexity and reliability.
- Heat-precipitation assays offer a potentially simpler alternative for fibrinogen determination.
Purpose of the Study:
- To compare the accuracy and reproducibility of two heat-precipitation assays (Millar et al. and Schalm et al.) against a reference method (Ratnoff-Menzie) for plasma fibrinogen quantitation in multiple animal species.
- To evaluate the suitability of the Millar et al. assay for routine clinical use in veterinary diagnostics.
Main Methods:
- Blood samples were collected from various animal species, including humans.
- Plasma fibrinogen levels were measured using the Ratnoff-Menzie reference assay.
- Plasma fibrinogen was also quantitated using the Millar et al. and Schalm et al. heat-precipitation assays.
- Assay performance was evaluated based on accuracy (comparison to reference) and reproducibility.
Main Results:
- Both heat-precipitation assays significantly underestimated plasma fibrinogen levels when compared to the Ratnoff-Menzie reference assay.
- The Millar et al. assay demonstrated significantly better reproducibility than the Schalm et al. assay.
- The reproducibility of the Millar et al. assay closely approached that of the Ratnoff-Menzie method.
- The Millar et al. assay requires no specialized equipment, making it practical for clinical settings.
Conclusions:
- Heat-precipitation methods, particularly the Schalm et al. assay, tend to underestimate plasma fibrinogen concentrations in animals.
- The Millar et al. heat-precipitation assay offers acceptable reproducibility and practicality for clinical veterinary use.
- The Millar et al. assay is recommended for routine clinical assessment of plasma fibrinogen in animals due to its simplicity and reasonable accuracy.
