The initial evaluation should include an assessment accounting for the common manifestations. Other assays of disease activity have been the subject of intense investigation, including serum angiotensin-converting enzyme level, gallium-67 scan, bronchoalveolar lavage fluid characteristics (CD4/CD8 ratio, total lymphocyte count), and numerous other biomarkers; unfortunately, none has consistently predicted disease course in multiple populations. Recent data have demonstrated that the presence of certain human leukocyte antigen (HLA) haplotypes (., HLA-DR17 and HLA-DQB1) confer good prognosis in certain European populations. 33 However, the usefulness of HLA typing in other populations has not been confirmed. For now, chest x-ray stage, demographic features, clinical involvement, and serial pulmonary function testing remain the best indicators in assessing prognosis and therapeutic decisions.