BioChemistry
Clinical biochemistry refers to the analysis of the blood plasma (or serum) for a wide variety of substances—substrates, enzymes, hormones, etc—and their use in diagnosis and monitoring of disease. Analysis of other body fluids (eg, urine, ascitic fluids, CSF) is also included. One test is very seldom specific to one clinical condition, and basic checklists of factors affecting the most commonly requested analytes are given below. Thus, rather than six tests that merely confirm or deny six possibilities, a well-chosen group of six tests can provide information pointing to a wide variety of different conditions by a process of pattern recognition. Biochemistry tests should be accompanied by full hematology, because evaluation of both together is essential for optimal recognition of many of the most characteristic disease patterns (see Clinical Hematology).
Before samples are collected, a list of differential diagnoses should already be established based on the history and clinical examination. Then, additional appropriate tests can be added to the basic panel below.
Making a diagnosis entails establishing a list of differential diagnoses based on the history and clinical examination. Based on this list, tests can be selected to include or exclude as many of the differentials as possible. Yet more tests may be necessary until only one of the original list remains to determine the diagnosis. If all differentials are excluded, then the list must be reevaluated. It is not good practice to order tests without a sensible differential list unless the animal presents without definitive clinical signs.
