Purpose: The term diffuse parenchymal lung disease (DPLD) refers to a group of disorders affecting the lung parenchyma that can be categorized into those of known and those of unknown etiology. Early diagnosis is important since some forms of DPLD are characterized by a rapid progression to respiratory failure. Notwithstanding the fact that recently guidelines have been published, some issues concerning the practical evaluation of a patient with suspected DPLD remain unclear.
Methods: In this article we propose a practical approach to the diagnosis and differentiation of DPLD. Moreover, a critical appraisal is provided based on the current literature and frequent pitfalls are highlighted.
Conclusion: we propose a practical workup, but in spite of increasing evidence concerning the diagnosis of DPLD, further studies will be needed to clarify several issues for efficient investigation of newly diagnosed patients with DPLD.