Saliva: clinical and diagnostic usefulness. Review of the literature

Modern clinical pathology is mainly based on the analysis of blood samples, carried out through more and more sophisticated techniques. Being the blood test an invasive technique, it certainly reduces the possibility of carrying out blood analysis, especially in patients such as children, old people, handicapped people and every person who needs continuous biochemical or pharmacological monitoring. In these cases it is very important to find other body fluids that can be easily obtained and that can offer the same reliable data as blood. Due to some of its characteristics, sometime saliva may be a good alternative to venous blood, as it presents the same features of plasma or urine. The chemical analysis of saliva provides some information that are useful for metabolic, inflammatory, neoplastic and genetic diseases; furthermore radioimmunological dosages allow to assess small concentrations of active substances. On the basis of an accurate review of literature, the aim of this study is to analyse the importance of saliva in diagnosing and monitoring certain systemic diseases, the utilization of saliva in hormonal and pharmacological dosages and the use of saliva in some epidemiological studies. Finally, it is emphasized that saliva in monitoring may help to manage several clinical conditions.