A modern view on the clinical value of the study of oral fluid in the practice of a pediatrician

Abstract

Currently, the attention of the medical community to a non-invasive method of laboratory diagnostics - the study of oral fluid (oral, saliva, saliva test) in various fields of clinical medicine and mainly in adult patients has been updated. Saliva testing has shown good results, especially in the areas of genomics, microbiomics, proteomics, metabolomics, and transcriptomics. The review presents the possibilities of using a non-invasive method for infectious and non-infectious diseases in children. Saliva contains a wide range of protein DNA and RNA biomarkers that help detect many viral infections in children. Oral fluid tests for human immunodeficiency virus, hepatitis B virus have improved access to diagnostics for infants. Both serological and molecular analyzes of the oral fluid are suitable for routine examination and early detection of measles virus RNA, polyomaviruses. Angiotensin-converting enzyme-2 receptor expression was found in the saliva of children with COVID-19, which can be used to diagnose SARS-CoV-2. The saliva test is as effective as the standard test at identifying asymptomatic individuals in contact tracing. The possibilities of saliva diagnostics are positively assessed in transplantology. New biomarkers in saliva have been identified for the diagnosis of many somatic diseases in children. The role of oral fluid as an alternative to blood serum in patients with terminal renal failure, chronic kidney disease (determination of creatinine, urea) in both adults and children is shown. The data obtained may influence the recommendations for the treatment of patients. As a non-invasive method, the study of oral fluid is promising for the diagnosis, prognosis, monitoring of diseases, large-scale typing of children, and the search for new biomarkers.