The reticular network contributes to the staging of idiopathic lung fibrosis

The aspect of reticular fibers is not considered in the current classifications of lung fibrosis. The aim of our study was to evaluate the distribution and the architecture of the reticular fibers for potential use as a tissue marker of fibrosis severity. We included in our study 25 pulmonary samples obtained by video-assisted thoracoscopy surgery (VATS) from a number of 20 cases. The cases were subdivided according to four criteria into: degree II, III and IV. We noticed no significant changes in the reticular network from interalveolar septa to the cases scored with 0, an accumulation of reticular fibers in the interalveolar septa (stage II), the condensation and thick bundles with network disorganization in all areas affected by fibrosis (stage III), partial to full depletion of reticular fibers (stage IV). Depletion of reticular fibers was constantly associated with advanced fibrosis stages.