Aliquots of respiratory specimens (initially, specimens collected by bronchoalveolar lavage, BAL) from 200 patients at the NIH Clinical Center and the Washington Hospital Center will be analyzed using the customized microarray chip. The specimens will be collected as part of the patients routine clinical care. The results of the TessArray microarray analysis will not be available to the clinician and therefore will not have any effect on the clinical care of the patients.