Silicosis

Silicosis is an occupational lung disease caused by the inhalation of respirable crystalline silica dust. It is characterized by lung inflammation and fibrosis that most commonly affects the upper lobes and is classified as a form of pneumoconiosis. The disease occurs in chronic (simple and progressive massive fibrosis), accelerated, or acute forms, depending on the intensity and duration of exposure.

Common symptoms include shortness of breath, cough, fatigue, and cyanosis in severe cases. Because its clinical and radiographic features can resemble those of tuberculosis, pneumonia, or pulmonary edema, silicosis is sometimes misdiagnosed. There is no curative treatment; management focuses on symptom control and the prevention of complications.

Silicosis is largely preventable through effective workplace controls that limit airborne silica exposure, such as engineering controls, ventilation, and appropriate respiratory protection.

Signs and symptoms

Because chronic silicosis is slow to develop, signs and symptoms may not appear until years after exposure. Signs and symptoms include:

Dyspnea (shortness of breath) exacerbated by exertion

Cough, often persistent and sometimes severe

Fatigue

Tachypnea (rapid breathing) which is often labored

Loss of appetite and weight loss

Chest pain

Fever

Gradual darkening of skin (blue skin)

Gradual dark shallow rifts in nails eventually leading to cracks as protein fibers within nail beds are destroyed

In advanced cases, the following may also occur:

Cyanosis, pallor along upper parts of body (blue skin)

Cor pulmonale (right ventricle heart disease)

Respiratory insufficiency

Patients with silicosis are particularly susceptible to tuberculosis (TB) infection—known as silicotuberculosis. The reason for the increased risk—3 fold increased incidence—is not well understood.