Calcified mitochondria in epithelial cells of the respiratory tract in upper respiratory thermal injury.

Multiple hematoxyphilic small granules were found in the respiratory columnar cells in smears from bronchial washings in a symptomatic boy who had suffered from extensive burns in his face and was suspected to had developed thermal injury of the upper respiratory tract. These granules proved to be immunoreactive for mitochondria antigen antibodies and to contain calcium salts after the von Kossa stain. Calcified mitochondria may represent a peculiar phenotype of thermal injury to the bronchial lining cells.