Findings of Denim-Sandblasting-Induced Silicosis : a cross-sectional study

Background: Denim sandblasting is as a novel cause of silicosis in Turkey, with reports of a recent increase in cases and fatal outcomes. We aimed to describe the radiological features of patients exposed to silica during denim sandblasting and define factors related to the development of silicosis. Methods: Sixty consecutive men with a history of exposure to silica during denim sandblasting were recruited. All CT examinations were performed using a 64-row multi-detector CT (MDCT). The nodules were qualitatively and semiquantitatively analyzed by grading nodular profusion (NP) on CT images. Results: Silicosis was diagnosed radiologically in 73.3% of patients (44 of 60). The latency period (the time between initial exposure and radiological imaging) and duration of silica exposure was longer in patients diagnosed with silicosis than in those without silicosis (p < 0.05). Nodules were present in all cases with centrilobular type as the commonest (63.6%). All cases of silicosis were clinically classified as accelerated and 11.4% had progressive massive fibrosis (PMF). Mild NP lesions were the most prevalent in all six zones of the lung. The NP score was significantly correlated with the duration of silica exposure, the latency period, presence of PMF, and pleural thickening. Enlarged lymphadenopathy was present in 45.5% of patients. Conclusions: The duration of exposure and the latency period are important for development of silicosis in denim sandblasters. MDCT is a useful tool in detecting findings of silicosis in workers who has silica exposure. Background Silicosis is an incurable lung disease caused by the inhalation of dust containing free crystalline silica. Extremely high exposures are associated with a short latency and rapid disease progression [1]. The condition is irreversible and progresses even when exposure stops. Silicosis is one of the oldest occupational diseases and kills thousands of people worldwide every year. Silicosis occurs in two distinct clinical forms: acute silicosis, also known as silicoproteinosis, and classic or chronic silicosis. Acute silicosis occurs following exposure to a large quantity of silica, most frequently as a result of sandblasting. Classic or chronic silicosis is characterized by the development of nodular infiltrative lung disease [2] and occurs following long-term exposure (i.e., 10-20 years) to a low concentration of silica dust. Accelerated silicosis is similar to classic silicosis, but occurs following exposure to higher dust concentrations for a shorter period (as little as 5 years) [3]. Silicosis has two radiological forms: simple and complicated [2,3]. Denim sandblasting was recently identified as a novel cause of silicosis in Turkey, with reports of a recent increase in cases and fatal outcomes [4-8]. Denim sandblasting uses silica-containing sand as an abrasive on blue jean surfaces to produce a "worn-out" look. This exposure is more dangerous than others because it involves intense exposure for long periods under poor hygienic conditions and in the absence of ventilation systems or respiratory protection [5-8]. Acute silicosis can also occur in quartzite millers, tunnel workers, silica flour workers, and workers in the scouring powder industry [9,10]. Although chest radiography is the most convenient imaging technique for diagnosing and monitoring the progression of silicosis, it has some limitations in the assessment of pneumoconiosis [11]. Thin-section com* Correspondence: cihanakgul@gmail.com 1 Dicle University School of Medicine Department of Radiology 21280,