A scientific study conducted at the State University of Campinas (UNICAMP) in São Paulo State, Brazil, has identified genetic factors associated with the severity of acute viral bronchiolitis. The study was supported by the Sao Paulo Research Foundation - FAPESP. Its results were published in the journal Gene.
Principal investigator for the study and a professor at UNICAMP's Medical School (FCM-UNICAMP), José Dirceu Ribeiro recalls that bronchiolitis is the most common disease during the first year of life, and also the leading cause of hospitalization during this period of infancy worldwide.
Bronchiolitis, which is basically an infection of the respiratory tract that causes acute inflammatory damage to the bronchioles, is mostly a disease with minor consequences. However, 1%-3% of its patients require hospitalization, with some of them needing supplemental oxygen. A smaller proportion requires ICU treatment including mechanical ventilation.
"Detecting genetic associations in cases of acute viral bronchiolitis is the first step toward the development of tests to predict the possible clinical outcome for each patient diagnosed with the disease soon after arrival at the emergency room," said Fernando Augusto de Lima Marson, a researcher at FCM-UNICAMP and one of the authors of the article.
The new study set out to find correlations between genetic factors and the severest forms of acute viral bronchiolitis in patients that did not present any of the risk factors, such as prematurity, a history of lung disease, and passive smoking. "A very significant proportion of patients present with no risk factors, and the question arises in these cases of how to explain progression of the disease to its most severe form," Ribeiro said.
Alfonso Eduardo Alvarez, et. al. Association between single nucleotide polymorphisms in TLR4 , TLR2 , TLR9 , VDR , NOS2 and CCL5 genes with acute viral bronchiolitis. Gene, 2018; 645: 7 DOI: 10.1016/j.gene.2017.12.022