Novel Biomarkers for Posterior Urethral Valve

The posterior urethral valve (PUV) is one of the main causes of congenital obstruction of the lower urinary tract in pediatrics. Its occurrence, although rare, can cause chronic kidney disease (CKD), with frequent progression to end stage kidney disease. Therefore, the development of new diagnostic strategies, such as biomarkers, is crucial to better assess the prognosis of patients with PUV. We aimed to review the literature on traditional and new biomarkers in PUV. For that, searches were performed in PubMed/MEDLINE, Scopus and SciELO databases. To systematize the search, terms such as "Posterior Urethral Valve", "Prognosis", "Biomarkers" and variations described in the Medical Subject Headings (MeSH) database were used. The literature showed new biomarkers of disease prognosis, with emphasis on inflammatory cytokines, proteomics and genomics techniques, as well as classic biomarkers, focusing on serum creatinine and urine osmolality. As for biomarkers recently described in the literature, the 12PUV, a set of 12 fetal urinary peptides that accurately predicted postnatal kidney function in fetuses with PUV, stands out. Similarly, oxidative stress markers, inflammatory cytokines and components of the renin-angiotensin system (RAS), when increased, were indicative of severe kidney outcomes. Genetic alterations also correlated to worse prognosis among patients with PUV, with emphasis on RAS polymorphisms and, specifically, those affecting the angiotensin-converting enzyme (ACE) and the angiotensin II receptors types 1 and 2 (AGTR1 and AGTR2) genes. Considering the severity of the PUV condition, the identification of sensitive and cost-effective biomarkers, beyond improving diagnosis, may favor the investigation of new therapeutic strategies.