Pitfalls in the interpretation of common biochemical tests

The development of multichannel automated analysers has led to the majority of hospital patients having a biochemistry profile performed at some point during their care. Whilst these investigations are often viewed as simple tests, there are many pitfalls in the interpretation of their results, pote ntial for error putting the patient at risk of over investigation or even e rroneous diagnosis. There are many reasons for spurious abnormalities which can falsely raise or lower the concentrations of analytes, both prior to s ample handling or during the analytical process itself. Lack of tissue spec ificity of enzymes may make interpretation of their activities difficult wi thout additional tests. Hitherto unsuspected disease may also contribute to confusion in test interpretation.