The value of bronchoalveolar lavage for discrimination between healthy and diseased individuals.

BACKGROUND: Bronchoalveolar lavage (BAL) is standard diagnostic procedure. Procedural recommendations have been made by pneumological societies including normal values for interpretation of BAL cytology. These normal values derive from small studies in healthy volunteers and have never been analysed for their sensitivity and specificity. OBJECTIVES: This study aims to analyse sensitivity and specificity of these normal values by assessing lavage cell composition in healthy and diseased individuals. METHODS: More than 6000 BAL were retrospectively analysed for their cellular distribution including BALs of 250 healthy individuals. All BALs were obtained under similar conditions. RESULTS: Bronchoalveolar lavage cytology of healthy individuals mirrors data from previous studies with smoking being the most important manipulator of BAL cytology. Analyses of proposed normal values demonstrate specificity between 80% and 95%, whereas sensitivity ranges between 35% and 65%. Using different mathematical models, a value summing up the differences to ATS-proposed normal values of the cytological pattern was found to best discriminate between healthy and diseased individuals with a sensitivity of nearly 60% with a predefined specificity of 95%. CONCLUSION: In summary, our analysis confirmed prior results for healthy volunteers and enlarged these findings by analysing sensitivity and specificity of lavage results in an independent validation cohort of diseased individuals. Thereby, the study may influence the acceptance of BAL in the diagnostic workup of individuals with pulmonary diseases. Additionally, the study proposes a novel value that facilitates lavage interpretation and may therefore be useful in further studies.

[Sarcoidosis]. / Sarkoidose.

Sarcoidosis is a rare granulomatous disease mainly affecting lymph nodes and the lungs but joints, bones, muscles and other organs can also be affected. Sarcoidosis therefore represents an important differential diagnosis to various rheumatic diseases. For the diagnosis and differential diagnostic clarification, bronchoscopy including endobronchial ultrasound-guided fine needle aspiration of mediastinal and hilar lymph nodes represent the main procedures. Because of the high spontaneous remission rate initiating a therapy requires a therapeutic goal defined by sarcoidosis-associated functional organ impairment, especially for acute sarcoidosis. Cortisone represents the most commonly administered medication whereas methotrexate and azathioprine are well-established second-line medications. Antibodies which neutralize tumor necrosis factors (TNF) are a potential third-line therapy.