Silicosis: Causes and Treatments

Silicosis is commonly understood as a potentially fatal and irreversible disease that affects the fibrotic pulmonary system. The illness develops as a result of exposure to large quantities of silica dust. It is rarely manifest when one has small amounts of silicon in his or her body. In other words, it only occurs as a result of continuous exposure to the causative agent. Casual or short-term exposure is not considered a major factor in the diagnosis of the illness (Greenberg, Waksman & Curtis 2007).

Its severity is determined by latency periods, which are classified as acute, accelerated or chronic, depending on the magnitude of silica concentration in the lungs. The disease has been retrospectively studied by numerous scholars, and it has been given various names such as stone cutter disease, potter’s rot and dust consumption illness, among others. It is common among people working in fields such as mining and construction who were exposed to dust for long periods.

The “disease results from a period of prolonged breathing of dust, which contains silica, also know as quartz” (Aghilinejad et al. 2012, p. 40. This is the main component in many materials used in the mining and drilling sectors (Aghilinejad et al. 2012). When individuals breathe dust with quartz particles in it, the impact is the same as breathing fine glass particles that end up cutting their lungs and creating scars in their lungs. This limits the capacity of the lungs to extract oxygen from the air, and gradually weakens them until they can no longer provide sufficient oxygen to function normally. Subsequent respiratory complications and infections are often fatal. Despite the existence of the condition for centuries, there is still no specific treatment or cure, which makes it worrying because there is rarely hope for recovery in chronic cases.

There have been several clinical and pathological varieties of silicosis that have been identified in the last few decades. Some of these are silicoproteinosis complex, progressive massive fibrosis and interstitial fibrosis. In many cases, after postmortem examination of victims with the illness, dark pulmonary tissue, which is commonly associated with distended hilar and peribronchial lymph nodes, is found. As a result, lesions develop with varying degrees of calcification that may range from as little as a few millimetres to as much as centimetres or more in diameter (Greenberg et al. 2007).

The aggressive condition is known as progressive massive fibrosis, which leads to central necrosis characterised by cavitation. This results in secondary infections such as tuberculosis. Under a microscope, biopsies of the affected lungs are often found to contain silica macrophages. The nodules are in medical terms called histological tornadoes (Naghadehi, Sereshki & Muhammad 2013). They are surrounded by inflammatory cells that result from the induction of fibrous reactions in normal blood vessels and airways in the lungs. Polarised light microscopy in most cases reveals the presence of small particles in the centre of the silicosis nodules, which are a result of inhaled quartz mixed with dust (Greenberg et al. 2007).

Several studies on the subject have investigated the correlation between pulmonary and silica burden as well as the ensuing development of silicosis (Greenberg et al. 2007). A probable connection has been made between the increase in the mass of silica collected within the surface area of the lungs and the level of seriousness of the condition. Nevertheless, it has also been speculated that the presence or absence of other mineral particles may influence the extent to which the condition affects an individual.

The molecular understanding of the disease is mainly arrived at after a clinical diagnosis, which is based on the existence of documented evidence of a patient’s exposure to the causative chemical agent. Thus, the history of a patient has to be substantiated with evidence such as chest radiographs, which confirm the presence or absence of nodular opacities. However, the process is not a straightforward one because the differential diagnostic strategies for it also include tests for fungal infections, tuberculosis, sarcoidosis and even pulmonary fibrosis (Greenberg et al. 2007).

It is classified by the international labour (ILO) office through a standardised radiographic approach, which sets guidelines that need to be taken into account when grading cases of the disease (Aghilinejad et al. 2012).

The guidelines include the extent of pleural envelopment and the dimensions as well as a profusion of opacities. Furthermore, the qualities of the X-rays need to be considered because using low-quality X-rays may compromise the integrity of the results and confound the accuracy of a radiological classification. The ILO standards classify pulmonary nodules measuring 1.5 to 3 millimetres as “p” while those between 3 and 10 are categorised as “r”. Irregularly shaped ones are classified as “s” “t” and “u” while those found to be remarkably large are designated A (Aghilinejad et al. 2012; Greenberg et al. 2007).

While there have been several attempts to treat the disease, the most effective way of preventing the condition is keeping people away from the source of the chemical. This mostly involves providing protective equipment to miners and other people whose jobs place them in proximity with dust that contains silica. In addition, ILO has focused on educating and informing those who may be exposed to take precautions because the majority of those who are affected are ignorant of the risk. In the last few years, doctors have made the connection between silicosis and tuberculosis (Greenberg et al. 2007).

As a result, they often prescribed similar medications such as bronchodilators, which are meant to assist patients to breathe more easily. In case of actual infections resulting from silicosis, doctors prescribe antibiotics, but there are few benefits to specialised treatments. People suffering from this condition are often at a very high risk of developing TB and other respiratory conditions that interfere with the body’s immune system. Therefore, individuals with the illness are encouraged to take frequent tests to ensure that they have not also been exposed to the bacterium that causes TB (Greenberg et al. 2007).

References

Aghilinejad, M, Naserbakht, A, Naserbakht, M, & Attari, G, 2012, ‘Silicosis among Stone-Cutter Workers: A Cross-Sectional Study, Tanaffos, vol. 11, no. 2, pp. 38-41.

Greenberg, MI, Waksman, J, & Curtis, J, 2007, ‘Silicosis: a review’, Disease-a-Month, vol. 53, no. 8, pp. 394-416.

Naghadehi, ZM, Sereshki, F, & Mohammadi, F, 2014, ‘Pathological study of the prevalence of silicosis among coal miners in Iran: A case history’, Atmospheric Environment, vol. 83, no. 214, pp. 1-5.