High rate of viral identification and coinfections in infants with acute bronchiolitis.
OBJECTIVE
To determine the viruses and risk factors associated with hospital and intensive care unit (ICU) admissions in infants with acute bronchiolitis.


BACKGROUND
Bronchiolitis is a major cause of morbidity in infants. Widespread use of molecular-based methods has yielded new insights about its etiology, but the impact of viral etiologies on early outcomes is still unclear.


METHODS
Seventy-seven infants with bronchiolitis who were under two years of age and visited an emergency unit were included. Using molecular-based methods, samples were tested for 12 different respiratory viruses. Logistic regression models were used to identify clinical and virological variables associated with the main endpoints: hospital admission and ICU admission.


RESULTS
We identified at least one virus in 93.5% of patients, and coinfections were found in nearly 40% of patients. RSV was the most common pathogen (63.6%), followed by rhinovirus (39%). Identification of RSV was only associated with an increased risk of hospital admission in the univariate model. Younger age and enterovirus infection were associated with an increased risk of hospital admission, while atopy of a first-degree relative showed a protective effect. Prematurity was associated with an increased risk of admission to the ICU. Coinfections were not associated with worse outcomes.


CONCLUSIONS
Molecular-based methods resulted in high rates of viral identification but did not change the significant role of RSV in acute bronchiolitis. Younger age and enterovirus infection were risk factors for hospital admission, while prematurity appeared to be a significant risk factor for admission to the ICU in acute viral bronchiolitis.
Departamento de Saúde Materno Infantil, Hospital Israelita Albert Einstein, São Paulo, Brazil.
Milena Siciliano
MS
Nascimento
Andréa Vieira de
AV
Souza
Adriana Vada de Souza
AV
Ferreira
Joaquim Carlos
JC
Rodrigues
Sulim
S
Abramovici
Luiz Vicente Ferreira da
LV
Silva Filho
D000208:Acute Disease; D001938:Brazil; D001990:Bronchiolitis, Viral / Q000150:complications / Q000821:virology*; D015331:Cohort Studies; D004770:Enterovirus / Q000302:isolation & purification; D005260:Female; D006760:Hospitalization; D006801:Humans; D007223:Infant; D015278:Intensive Care Units, Pediatric; D016015:Logistic Models; D008297:Male; D010850:Picornaviridae Infections / Q000150:complications / Q000821:virology; D016133:Polymerase Chain Reaction; D011446:Prospective Studies; D012136:Respiratory Syncytial Viruses / Q000302:isolation & purification; D012229:Rhinovirus / Q000302:isolation & purification; D012307:Risk Factors
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