%0 Journal Article %T Diagnostic approach to interstitial pneumonias in a single centre: report on 88 cases %A Dirk Theegarten %A Heike M¨¹ller %A Francesco Bonella %A Jeremias Wohlschlaeger %A Ulrich Costabel %J Diagnostic Pathology %D 2012 %I BioMed Central %R 10.1186/1746-1596-7-160 %X 88 patients with interstitial pneumonia that underwent open lung biopsies were investigated. Histology and clinical records were available for review. Diagnosis was made in three steps: first on the sole basis of histology, second with clinical information given initially and third, on the basis of an interdisciplinary case evaluation.63 patients (72%) were diagnosed as idiopathic interstitial pneumonias according to ATS/ERS criteria. Further 10 (11%) cases of hypersensitivity pneumonitis, 7 (8%) Langerhans cell histiocytosis and 8 (9%) interstitial pneumonias of other known causes or associations were detected. Histological patterns alone agreed with the final diagnosis in 67%. In 82% histology and clinical information given to the pathologist could provide correct diagnosis. In the rest of cases, especially in non idiopathic interstitial pneumonias, an interdisciplinary case evaluation was needed.Diagnosis of interstitial pneumonias by open lung biopsies needs sufficient clinical information. Because of the overlap of histological patterns, an interdisciplinary case evaluation that includes at least one clinical expert and one pathologist with excellent expertise and the follow-up of the patients is necessary to find correct diagnosis in all cases.The virtual slides for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/5031706258025129 webciteDiffuse interstitial lung diseases (ILD) are disorders with a large spectrum of possible underlying causes. Most of ILD belong to the group of idiopathic interstitial pneumonias (IIP). But these diagnoses can only be made after exclusion of known etiological factors or associations.Pulmonary fibrosis was first described by VON B¨¹HL in 1872 [1]. The first generally accepted classification of idiopathic interstitial pneumonia was introduced by LIEBOW in 1975 [2]. He distinguished usual interstitial pneumonia (UIP), bronchiolitis obliterans with interstitial pneumonia (BIP), desquamative interstitial %U http://www.diagnosticpathology.org/content/7/1/160