On the whole, sarcoidosis of the lung has a good prognosis with the exception of a few cases where it takes a progressive course. In such instances it would be useful to enable a prognosis already at the time of diagnosis by means of clinical parameters or inflammation markers. We examined a number of cell-biological inflammation parameters in the serum and bronchoalveolar lavage fluid of 72 patients in the x-ray stages I and II with and without Löfgren's syndrome (phenotyping of lymphocytes, interleukin-1 alpha, soluble interleukin-2 receptors [sIL-2R], interleukin-6, interleukin-8, platelet-derived growth factor, procollagen-3 peptide) and followed up these patients for one year by clinical parameters. It was found that markers of the active lymphocytic inflammation were mostly associated with spontaneous remission during the follow-up period. Hence, acute lymphocytic inflammation is a favourable prognostic sign and should not prompt premature treatment with cortisone.