Pulmonary Fibrosis Flare-Ups Often Not Due to Viruses
Viral infection detected in a minority of acute exacerbation of idiopathic pulmonary fibrosis
MONDAY, Feb. 28 (HealthDay News) -- Acute viral infection is not detected in the majority of cases of acute exacerbation of idiopathic pulmonary fibrosis (IPF), according to a study published online Feb. 25 in the American Journal of Respiratory and Critical Care Medicine.
Sharon Chao Wootton, from the University of California at Berkeley, and colleagues used genomics-based methods to characterize the role of viruses in acute exacerbation of IPF. Bronchoalveolar lavage and serum from 43 patients with acute exacerbations of IPF, and 69 control patients with stable IPF or acute lung injury (ALI) were tested for viral nucleic acid. Genomic-based testing included multiplex polymerase chain reaction (PCR), pan-viral microarrays, and high throughput copy DNA sequencing.
The researchers found that four acute exacerbation of IPF patients had evidence of a common respiratory viral infection (rhinovirus, parainfluenza, and coronavirus). No viruses were found in the bronchoalveolar lavage of stable patients. Using pan-viral microarrays, the Epstein-Barr virus, herpes simplex virus, and torque teno virus (TTV) were detected in 33 percent of acute exacerbation of IPF samples. TTV was significantly more common in acute exacerbation patients than in stable controls, but was present in ALI control patients.
"Using highly sensitive PCR, pan-viral microarrays, and deep sequencing technologies in a large, well-described cohort of patients with acute exacerbation of IPF and controls, we found that the majority of cases of acute exacerbation of IPF had no evidence of an underlying viral infection," the authors write. "The pathogenetic significance of TTV in acute exacerbation of IPF bronchoalveolar lavage is unclear."