Background: Not all the patients with sarcoidosis need pharmacological therapy, and the decision to start therapy is based mainly on clinical conditions. The aim of this study was to evaluate the prognostic value of the leukocyte and lymphocyte subpopulations in the bronchoalveolar lavage fluid from these patients.

Methods: Thirty-three nonsmoking patients with sarcoidosis were included and classified based on the presence of Löfgren’s syndrome (n= 11), the radiological stage (12 at Stage I, 17 at Stage II, and 4 at Stage III), and their follow-up. Differential leukocyte subsets and the lymphocyte subpopulations were determined by flow cytometry.

Results: The percentage of neutrophils was lower in patients with Löfgren’s syndrome (P= 0.038) and in patients at Stage I (P= 0.002). Patients with a poor outcome had a higher percentage of neutrophils (P= 0.004) and NK cells (P= 0.023) than those with a stable disease. Finally, a higher percentage of NK cells was found in those patients who needed a steroid treatment (P= 0.012). Conclusions: Increased percentages of neutrophils and NK cells in the bronchoalveolar lavage fluid from patients with sarcoidosis are associated with a poor outcome and a higher probability to need steroids treatment. The percentage of neutrophils was also lower in patients with Löfgren’s syndrome. q 2006 International Society for Analytical Cytology