Adenovirus pneumonia in infants and factors for developing bronchiolitis obliterans: A 5‐year follow‐up

Abstract

To describe clinical, pulmonary function, and chest tomography profiles in a 5-year follow-up of infants with adenovirus pneumonia and determine the factors that potentially contributed to the development of bronchiolitis obliterans (BO). We prospectively assessed 45 hospitalized infants with adenovirus pneumonia with additional follow-up for 5 years. At the end of the study, pulmonary function by impulse oscillometry technique (IOS) and chest tomography were performed in the 38 surviving patients (mean 5.7 years of age). We divided the population between those who developed chest tomography evidence of BO and those who did not. Most of the children developed adenovirus infection before 2 years of age. During the 5 years of follow-up, almost half (47.4%) developed BO. Children who developed BO had significantly more respiratory compromise (intensive care admission, need for mechanical ventilation and for oxygen therapy, and systemic corticosteroid and beta agonist use) during their adenovirus pneumonia episode than those who did not develop BO. Only 33.3% of children with BO had normal impedance compared with 85% in the no BO group. Children who developed BO had significantly higher levels of Zrs, R5, X5 and predicted Zrs, R5, and X5 and frequency. However, there were no differences in the beta 2 agonist response between the children with and without BO (94% vs. 80%, respectively). This study represents the spectra of adenovirus pneumonia ranging from relatively mild to severe and fatal cases. Children with severe pulmonary compromise are usually more prone to develop BO.

Bronquiolite obliterante: perfil clínico e radiológico de crianças acompanhadas em ambulatório de referência

“…The most serious cases are associated with adenovirus infections, and types 3, 7 and 21 serotypes are responsible for the most severe conditions. Bacterial agents, such as Mycoplasma pneumoniae, type B Streptococcus, Legionella pneumophila and Bordetella pertussis, may also be associated with BO (3,11,12) . Virus infection is currently investigated by means of immunofluorescence in many centers, and the virus can be identified during the acute infection of the respiratory tract.…”

“…Three patients (8.5%) died during the first hospitalization or in the first six months after the diagnosis. A prospective study with patients with pneumonia due to adenovirus infection had a mortality of 18.4% in the first acute phase and no death during the five-year follow-up of patients that had BO (12) . Rales at pulmonary auscultation were a constant finding during outpatient follow-up, and wheezing was frequent during the acute respiratory phase.…”

Post-infectious bronchiolitis obliterans in children

“…A baixa saturação arterial de oxigênio pode ser um indicador de gravidade, e a hipoxemia já foi descrita em até metade dos pacientes 40 . Nos casos mais graves, pode ocorrer deformidade torácica, baqueteamento digital e sinais e sintomas de hipertensão arterial pulmonar (HAP) 17,18,41 .…”

“…Na técnica de oscilação forçada, os pacientes com BOPI apresentaram um aumento da resistência das vias aéreas mais acentuado do que pacientes que também apresentaram pneumonia por adenovírus, mas não desenvolveram BOPI 41 .…”

“…O prognóstico geral da função pulmonar foi ruim na maioria dos estudos publicados 5,9,28,41 . A maioria dos relatos revela que a espirometria dos pacientes seguidos em longo prazo apresenta o mesmo perfil de doença obstrutiva fixa de gravidade moderada a severa sem resposta aos broncodilatadores.…”