**4. Clinical presentation of asbestosis**

Asbestosis is an interstitial pulmonary process that develops into diffuse pulmonary fibrosis after a long latency period [42, 43]. The disease continues to progress even after the cessation of exposure, and the process is irreversible. One of the earliest symptoms may be dyspnoea, which is manifested at first only after strenuous exertion, but subsequently with less and less exertion, and eventually it appears even at rest. Another non-specific symptom and usually late manifestation of the disease is irritating and dry, usually non-productive cough, sometimes associated with chest pain [42, 44]. Pulmonary function changes are characterised mostly by a restrictive impairment [27, 28, 42–44]. Later, obstructive airway impairment may also occur [27, 28]. On chest radiographs, small irregular opacities appear initially in the lower lung fields that may enlarge with more advanced disease and involve also middle lung fields [27, 42–44]. Characteristic features of asbestosis on high-resolution computed tomography (HRCT) include fibrotic intralobular interstitial thickening and interlobular septal thickening, subpleural lines and opacities, parenchymal bands, ground-glass opacities and, in more severe disease, variable honeycombing [27].
