Clotting factors under Factor

Smyth et al. 1936). In some cases, moderate elevations in white cell counts are observed, perhaps in response to necrosis in the liver or kidneys. In a few cases, mild anemia is observed (Gray 1947), and occasionally this may become severe (Straus 1954). The mechanism underlying the blood dyscrasia is not known, but anemia might be secondary to internal hemorrhaging as a result of decreased synthesis of clotting factors by the liver (Guild et al. 1958 Stevens and Forster 1953 Straus 1954). 

Toxic effects to the liver are studied under the topic of hepatotoxicity, and substances that are toxic to the liver are called hepatotoxins. Much is known about hepatotoxicity from the many cases of liver toxicity that are a manifestation of chronic alcoholism.6 Liver injury from excessive alcohol ingestion initially hampers the ability of the organ to remove lipids, resulting in their accumulation in the liver (fatty liver). The liver eventually loses its ability to perform its metabolic functions and accumulates scar tissue, a condition known as cirrhosis. Inability to synthesize clotting factors can cause fatal hemorrhage in the liver. 

The word factor is often used during research when it is not certain what the nature of a substance under investigation is—whether protein, fat, carbohydrate, or something else. Even after its identity is pinned down, however, sometimes the old name continues to be used. In the blood-clotting pathway, all factors are proteins. 

Serum contains more than 100 different proteins, each under separate genetic control. They are transport proteins for hormones, vitamins, lipids, metals, pigments, and drugs enzymes enzyme inhibitors (proteinase inhibitors) hormones antibodies clotting factors complement components and kinin precursors. Quantitation (by radial immunodiffusion, electroimmunoassay, nephelometric methods, enzyme-linked immunological methods, and radioimmunoassay) of the various constituents of serum is of value in diagnosing and following the course of certain diseases. Several of these proteins are discussed elsewhere in the text. 

Determination of the potency of Factor VIII is also difficult. This is normally measured by the abiUty of the sample to correct the clotting time of plasma deficient in Factor VIII. A number of methods and practices have evolved for this purpose (231), but these give very different results, particularly when activation of products may also occur (232). International standards have been used, but further standardization of the analytical method and harmonization of working standards is underway (233,234) under the auspices of the ISTH and the EC. 

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