Today, most immunochemistry methods for the
determination of proteins, peptides, drugs, and many small molecules are fully
automated, with good precision, excellent sensitivity, and a short reaction
time. However, inaccuracy due to poor standardization and the presence of
interfering substances in biological samples is still a serious and
life-threatening issue. Proper validation of methods and quality assurance have
little effect on the frequency of occurrence of false-positive or false-negative
results, which, if unrecognized, may lead to patient misdiagnosis, unnecessary
treatment, or even unnecessary surgery. Deep knowledge of the basic principles
of immunochemical methods (antigen-antibody reaction, standardization, matrix
effect, limit of detection, cross-reactivity, etc.), sources of
analyte-independent interferences (preanalitycal errors, the presence of binding
proteins, the presence of autoantibodies), and analyte-dependent interferences
(presence of heterophilic antibodies, high-dose effect) are very important to
understand, detect, reduce, and/or eliminate the interferences. This book helps
to reduce false results and, at the same time, improve patient care and patient
safety.