Induced sputum and occupational diseases other than asthma.

PURPOSE OF REVIEW: Induced sputum noninvasively provides information on cellular and soluble material from airways. It has been successfully applied for assessing airway inflammation in asthma and chronic obstructive pulmonary disease, producing reliable results comparable to biopsy and bronchoalveolar lavage. Induced sputum research in the field of occupational medicine has mainly focused upon occupational asthma, and less to other types of occupational diseases.

RECENT FINDINGS: Particulate size distribution in induced sputum samples points to accumulation over time, leading to the consideration that this measurement may serve as a time-dependent marker for biological monitoring. Qualitative analysis of chemical composition of induced sputum particles is well correlated to the chemical elements spectrum in bronchoalveolar lavage lung cells and in biopsy thin sections. T cell subsets in induced sputum can be used as a marker of granulomatosis in chronic beryllium disease. Cytokines retrieved from induced sputum samples in exposed workers show a differential pattern compared to nonexposed workers.

SUMMARY: Induced sputum is a well tolerated, noninvasive technique that is opening a new window in the field of occupational diseases of the lung and can be integrated into the well established criteria for diagnosing and monitoring these diseases, especially when invasive techniques are clinically contraindicated or impractical.