The potential of the immunological markers of sarcoidosis in exhaled breath and peripheral blood as future diagnostic and monitoring techniques.

Sarcoidosis is characterised by non-caseating granulomatous inflammation, with exaggerated immune responses at sites of disease and derangements of normal tissue architecture. The lungs are most commonly involved and progressive inflammation may result in pulmonary fibrosis. The immunopathogenesis and aetiology remain uncertain, which has made it difficult to identify a single sufficiently sensitive or specific diagnostic marker. Further investigation is needed to identify sensitive and specific markers of disease, such as in peripheral blood and exhaled breath condensate (EBC). Identification of disease markers may also be useful for investigating disease activity and predicting progression to fibrosis. This review explores the literature on the cytokine profiles of blood and bronchoalveolar lavage lymphocytes following ex vivo stimulation, as well as disease markers measured using the medium of EBC.