PT - JOURNAL ARTICLE AU - Ana Villar AU - Ferran Morell AU - Javier de Gracia AU - Mario Culebras TI - The value of lymphocytosis in bronchoalveolar lavage in the differential diagnosis between idiopathic pulmonary fibrosis and chronic hypersensitivity pneumonitis DP - 2011 Sep 01 TA - European Respiratory Journal PG - p4197 VI - 38 IP - Suppl 55 4099 - http://erj.ersjournals.com/content/38/Suppl_55/p4197.short 4100 - http://erj.ersjournals.com/content/38/Suppl_55/p4197.full SO - Eur Respir J2011 Sep 01; 38 AB - Introduction: Bronchoalveolar lavage (BAL) is a minimally invasive, well-tolerated bronchoscopy procedure which plays an important role in the diagnosis of interstitial lung disease (ILD). We assessed the value of lymphocytosis in BAL fluid for the differential diagnosis.Material and methods: Prospective study of all the 318 patients with ILD through 2004-2010. During the diagnostic process, cytological and immuno-histochemistry studies of BAL fluid were performed.Results: We studied 318 patients with ILD (57 FPI, 92 NH, 45 Sarcoidosis). BAL was performed in 230 patients (72%), obtaining median lymphocyte percentages of 8%, 20% and 25% in IPF, HP and Sarcoidosis respectively. Lymphocyte counts were >60% in non IPF patients, 5% of HP and in 2% of Sarcoidosis patients; were >30% in non IPF, 18% HP and 29% Sarcoidosis, and >20% in 5% IPF, 32% HP and 33% Sarcoidosis.In a study focused exclusively on chronic NH occurring with IPF criteria (ATS/ERS criteria) (n=60), three presented lymphocytosis >20% but were ultimately diagnosed with HP. Lymphocytosis >15% was found in 5/11 (45%) IPF and 3+3/11 (55%) of patients with final diagnoses HP. Lymphocytosis between 10-15% was present in 8/14 (57%) IPF and 6/14 (43%) HP. No significant differences were found in the cellular profile between IPF and HP.Conclusions: Lymphocytosis >20% is also a characteristic of HP and Sarcoidosis, since is very rarely found in IPF (5% in our series). In chronic HP the absence of lymphocytosis in BAL >20% does not rule out the diagnosis (35% diagnosed with HP in our series).This abstract is funded in part by Fis 1001577