Respiratory viruses: What is their role in acute exacerbations in children with cystic fibrosis?

Abstract

Background Respiratory viruses (RVs) are frequently present in the airways of patients with cystic fibrosis (CF) during pulmonary exacerbations (PEx). Method and Objectives This prospective, longitudinal study was performed to examine the role of RVs in acute exacerbations in children with CF. Sputum samples or additional midturbinate swabs were tested from all children using a polymerase chain reaction panel. The primary aims of the study were to determine the prevalence and etiologic role of RVs in exacerbations of CF and to compare changes with RV‐positive and RV‐negative infections. The secondary aims were to determine the predictive factors for RV‐related exacerbations. Results From 50 patients with PEx, 23 (48.9%) sputum samples were virus‐positive. With a combination of sputum and swab, viral positivity increased to 56%. The virus‐positive group presented more frequently with hypoxia (oxygen saturation <93%) than the virus‐negative group (P = .048). Virus‐positive exacerbations were not associated with an increase in colonization rates or greater lung function decline over 12 months. Conclusions RVs frequently present during PEx of CF. However, predicting viral infections is difficult in this group. Only the presence of hypoxia may raise the suspicion of an accompanying viral agent. The combination of sputum and nasal swab samples increases the diagnostic yield in viral infections of CF. Despite their high frequency, the presence of RVs had no impact on clinical outcomes, such as a decline in lung function and increased colonization rates.

Is there a role of viral infection in cystic fibrosis exacerbation in children?

“…Similarly, it was reported as the most common respiratory virus in exacerbations of CF in many other studies. 2,3,6,7 In our study, influenza A virus was detected in only 6.7% of patients although no one had a history of influenza vaccination. Similarly, a French study found that its prevalence was 9%.…”

“…A study detected that the only discriminatory feature of the children who were rhinovirus positive was lower oxygen saturation. 3 In conclusion, exacerbation in cystic fibrosis may be exaggerated by viral infections such as influenza A and enterovirus necessitating hospitalization which demonstrate the important role of vaccination and the role of awareness of treating the concomitant viral and bacterial infection. Also, a strong relationship was detected between some viruses such as enterovirus, human metapneumovirus and influenza and between bacterial infection.…”

“…2 The prevalence of viral respiratory infections varies significantly in the literature, ranging from 5 to 68%. 3…”

Is viral coinfection a risk factor for severe lower respiratory tract infection? A retrospective observational study

“…Although coinfection with other viruses is very common during influenza infection, 30 secondary bacterial infections may exist at a rate of 40% in LRTI associated with influenza A 31,32 . Therefore, we note that any secondary bacterial infection, which was not detected, might increase influenza A's severity.…”

Cystic fibrosis year in review 2020: Section 2 pulmonary disease, infections, and inflammation

“…Many factors can contribute to PEx. One such factor, viral infections, were found to be present in 56% of those with PEx in a prospective longitudinal study of 50 sputum expectorating children, ages 6–18 years 9 . Rhinovirus was the most common virus identified.…”