The aim of this study was to assess whether the cellular bronchoalveolar lavage fluid (BALF) profile, particularly the number of polymorphonuclear neutrophils (PMNs), is associated with disease severity of sarcoidosis and its usefulness in determining remission. Twenty-six nonsmoking outpatients with sarcoidosis were included in this study. The patients were divided into two subgroups according to the absolute number of PMNs in BALF: < or =0.2x10(4) cells x mL(-1) (group 1; n = 15) and >0.2x10(4) cells x mL(-1) (group 2; n = 11). The radiographic stage, high-resolution computed tomography (HRCT) findings, 67Ga lung uptake as well as lung function tests differed significantly between group 1 and 2. Follow-up revealed that 14 (93.3%) patients of group 1 compared to four (36.4%) of group 2 recovered spontaneously without the help of corticosteroids. In contrast, no differences were found in the number of lymphocytes in BALF nor in the serum angiotensin converting enzyme (sACE) level between both groups. The number of PMNs, the transfer factor of the lungs for carbon monoxide (TL,CO), the forced expiratory volume in one second (FEV1) and one of the HRCT subscores discriminated between patients with different disease progression. Of these parameters the PMNs appeared to be the only one which differentiated patients who demonstrated remission and those who deteriorated. In conclusion, these results indicate that the number of polymorphonuclear neutrophils in bronchoalveolar lavage fluid distinguish between sarcoidosis patients who demonstrated remission and those having a more severe course of the disease. Whether polymorphonuclear neutrophils may be considered as markers of disease activity and/or prognosis in sarcoidosis needs further investigation.