High Frequency of Gammaherpesvirus Infection in Idiopathic Pulmonary Fibrosis: Clinicopathological Correlations
F Calabrese, F Lunardi, B Nordio, G Marulli, M Della Barbera, M Saetta, F Rea. University of Padua Medical School, Padua, Italy
Background: Idiopathic Pulmonary Fibrosis (IPF) is a progressive fibrotic interstitial lung disease of unknown etiology. Several studies reported chronic viral infection as a potential cause of lung injury in IPF particularly focusing on herpesvirus infection. The aim of the study was to investigate the presence of different types of viruses, many of them with a well known tropism for the respiratory system (Epstein-Barr virus-EBV-; cytomegalovirus-CMV-; human herpes virus 6-HHV6-; adenovirus; rhinovirus; influenza A and B viruses; parainfluenzae viruses; parvovirus B-19; metapneumovirus and respiratory syncytial virus).
Design: Frozen lung samples from 30 patients with end-stage IPF requiring lung transplantation (mean age 55.9; 20 males and 10 females) were analyzed by polymerase chain reaction (PCR) and reverse transcriptase-PCR for detecting respiratory viruses. Lung samples from 10 patients (5 non implanted donor lungs and 5 other forms of interstitial lung diseases) were used as control group. Molecular findings were then correlated with different clinico-functional and morphological data.
Results: A higher frequency of viral infection was detected in IPF patients than the control group (14/30, 46.6% versus 1/10, 10%; p=0.04). Genomes of gammaherpesviruses were the only ones detected (7 EBV; 6 HHV-6; 3 CMV; 2 patients had double infections).Viral IPF cases showed increased value of mean pulmonary arterial pressure (mPAP 35.16.9 versus 16.82.1; p=0.04) and partial pressure of CO2 (43.82.1 versus 29.64.8; p=0.01) compared to the non viral IPF group. Muscular arteries were significantly thickened in viral compared to non viral IPF cases (5811.1 versus 39.911.2; p=0.03).
Conclusions: Our data confirm the association between IPF and gammaherpesviruses. The higher values of mPAP and a more extensive vessel remodeling in viral IPF cases could be related to a well known endotheliotropism of gammaherpesviruses.
Monday, March 9, 2009 1:00 PM
Poster Session II # 231, Monday Afternoon