Tomografia computadorizada do tórax em pacientes com fibrose cística: comparação de escore tomográfico em pacientes colonizados por Pseudomonas aeruginosa e por Staphylococcus aureus

Abstract

In Cystic Fibrosis (CF) chronic lung infection leads to irreversible structural abnormalities, progressive lung disease and respiratory failure, most common cause of death in CF. Bacterial infection in CF is usually related to specific agents: Staphylococcus aureus e Haemophilus influenzae usually infect younger patients. After this, Pseudomonas aeruginosa infection is associated with lung function deterioration and progression of structural lung disease. Assessment of CF lung disease includes monitoring of respiratory secretions microbiology, lung function and thoracic imaging. High resolution computed tomography of the lung (HRCT) is involved on early detection of structural airway and parenchymal abnormalities. These structural abnormalities can be assigned systematically through different scoring systems. The aim of this study was to compare the results of the modified Bhalla score for High resolution computed tomography of the lung from two groups of CF patients attending the CF Reference Center at Instituto Fernandes Figueira, Rio de Janeiro, Brazil. These two groups had different microbiological features: chronically infected by Pseudomonas aeruginosa (n = 26) and infected by Staphylococcus aureus (n = 15). High resolution computed tomography of the lung images were randomly and blindly scored using a modified Bhalla scoring system by two independent radiologists in two different moments. There was good intraobserver and interobserver variability and this observation indicates that the measurements are reliable and reproducible. Score results and abnormalities found in each group were compared. Final scores of Pseudomonas aeruginosa group showed more severe disease (radiologist 1: 13.5 and radiologist 2: 11.96) then the Staphylococcus aureus group (radiologist 1: 5.0 and radiologist 2: 5.07). Early detection of structural abnormalities associated to infection and its assessment through scoring systems may contribute to therapeutical approaches that can improve prognosis for CF patients.