Biomarkers and Protein Mass Expression Profiles in Bronchoalveolar Lavage From Patients With Lung Infiltrates

OBJECTIVE: The objective of this study is to analyze bronchoalveolar lavage (BAL) fluid from patients with lung infiltrates in order to discover new biomarkers and protein/peptide expression patterns that are associated with specific types of pulmonary diseases and infections. Bronchoalveolar lavage (BAL) is a standard method to obtain lower airway samples to evaluate pulmonary infiltrates in order to diagnose infection, malignancy or non-infectious inflammation. After collecting the BAL (during a clinically indicated brochoscopy), samples are routinely sent to the clinical microbiology laboratory for stains, cultures and molecular analysis. We have recently developed a rapid, culture-independent method to identify unique peptide markers in BAL that identify specific bacterial species. We are expanding the scope of 04-CC-0119 that was based originally on collection of BAL supernatant only, to now collect, analyze and store whole (unprocessed) BAL. The availabilty of new methods of analyzing BAL will broaden the scope of the study to analyze BAL proteins, lung cells, and microbial pathogens. This will allow improved characterization of the host response to lung inflammation and infection and help to assess the feasibility of using the culture-independent approach on clinical BAL samples to identify specific pathogens. POPULATION: The study population will include all patients undergoing bronchoscopy for clinical indications at the Clinical Center who provide informed consent for chart review blood draw (optional), and analysis of BAL, as described in this protocol. We plan to acquire BAL samples that reflect a spectrum of community-acquired and opportunistic pathogens associated with pulmonary disease. In addition analysis of a range of non-infectious pulmonary processes (e.g. acute lung injury, acute respiratory distress syndrome and engraftment syndrome) is important to develop measures of sensitivity and specificity. DESIGN: This is a prospective observational study. OUTCOME: The expected outcome is to: Develop a database of protein mass profiles of BAL fluid linked to specific microbiologic diagnoses. To collect, analyze and store BAL to validate the usefulness of the genoproteomic culture-independent method of microbial identification. To analyze lung cells associated with infectious or inflammatory pulmonary condidtions. Our plan is to acquire 1,000 specimens from the Clinical Center with a range of clinical diagnoses including bacterial, viral, parasitic and fungal infections and sterile inflammation. When a sufficient number of samples in an individual category is collected (approximately 20-30), the samples will be analyzed with current proteomic techniques.