We read with great interest the case reported by Bueno Palomino,1 which alerted pulmonologists to the occupational risks faced by sandblasting.

We would like to highlight the risks of a similar activity: sandblasting used in heavy industry, especially in shipbuilding to clean boilers and ship hulls. Abrasive blasting involves the projection of abrasive particles against a surface (often glass or metal) using compressed air. In 1949, the United Kingdom adopted regulations for blasting activities that severely restricted the use of abrasive products containing free silica. In 1992, the National Institute for Occupational Safety and Health recommended that the use of sand in abrasive blasting should be banned in the United States.

Silicosis in sandblasting workers in the shipbuilding industry represents the most aggressive form of the disease, with evidence of progressive massive fibrosis in about 40% of cases.2 Cases of silicoproteinosis have been reported in this group of patients.

Silicoproteinosis may develop after a relatively short period of heavy exposure to fine particulate silica (e.g., in sandblasting activities). The disease often progresses rapidly, manifesting within months or a few years after initial exposure. Symptoms include progressive shortness of breath that invariably leads to acute respiratory failure. Prognosis is very poor and most reported cases die within months. The pathological features of silicoproteinosis differ from those of chronic silicosis and resemble those of primary alveolar proteinosis. No effective treatment has been described and management consists only of supportive care.2–4

The high-resolution CT findings of silicoproteinosis consist of bilateral air-space disease manifesting as consolidation, ground-glass opacities, and centrilobular nodules. Punctate calcifications superimposed in areas of consolidation and calcified lymph nodes are commonly seen.3,4 (Fig. 1).

Fig. 1.

A 29-year-old man with silicoproteinosis. The patient was a sandblaster in the naval industry, with a history of exposure to silica of 2.8 years. CT scans of upper (A) and lower (B) lobes show numerous bilateral airspace nodules, some of them confluent (white arrows) with areas of consolidation in both lungs. Calcified mediastinal and hilar lymph nodes (black arrows) are also evident.

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Although it is difficult to envision the continued occurrence of silicoproteinosis in modern society, sporadic cases continue to be reported, especially in underdeveloped countries. Radiologists and pulmonologists should be aware of the clinical presentation and imaging patterns of this serious and progressive disease, which can rapidly lead to fatal outcomes after the onset of symptoms.