14 Usual Causes of Sarcoidosis
2. Race
People of African descent are more likely to develop sarcoidosis and often experience more severe disease than those of European or Asian backgrounds. Among African-American patients, the condition also tends to appear at a younger age and progress more aggressively, with chronic lung involvement occurring more often.
People of Scandinavian descent also show higher rates of sarcoidosis compared to other European groups. The reasons for these differences are not fully understood, but researchers believe both genetic factors and environmental exposure may contribute to risk.
Some evidence suggests that certain genetic markers may increase the likelihood of developing sarcoidosis in specific populations. These differences may affect how the immune system responds to inflammation or to potential triggers such as infections and environmental agents.
3. Hereditary
Genetic factors appear to influence how likely a person is to develop sarcoidosis. Studies show that the condition often runs in families, which suggests a hereditary link. For example, when one identical twin has sarcoidosis, the other twin has a higher chance of developing it as well.
Researchers have identified certain gene patterns that may affect how the immune system recognizes and reacts to foreign substances. People who inherit specific versions of these genes may be more likely to develop granulomas, the small clumps of inflammatory cells that characterize the disease.
Sarcoidosis also occurs more frequently in certain populations, such as people of African descent and those from Scandinavian backgrounds. This pattern further supports the idea that genes passed down through generations may increase susceptibility.
4. Tattoos
Tattoos can sometimes trigger skin changes in people with sarcoidosis. The body may react to tattoo ink or the skin trauma caused by tattooing by forming small clusters of inflammatory cells called granulomas. These may appear as raised, firm, or discolored patches within the tattooed area.
In some cases, sarcoidosis first becomes noticeable in an old scar or tattoo. A tattoo that suddenly swells, feels itchy, or changes in texture, even years after it was done, can be an early visible sign. Health experts also suspect that infections related to tattooing may contribute in certain cases.
Outbreaks of nontuberculous mycobacterial skin infections have been reported after tattoo procedures, and exposure to these bacteria may stimulate an abnormal immune response. While this link is not fully proven, it supports the idea that tattoo-related inflammation could act as a trigger in susceptible individuals.
5. Scar Tissue
Scar tissue develops when the body repairs damage caused by ongoing inflammation in sarcoidosis. The immune system forms tiny clumps of cells called granulomas in response to what it perceives as a threat.
When these granulomas persist over time, they can heal through a process called fibrosis, which leads to the formation of scar tissue. The lungs are the most commonly affected organs. As scarring builds up, lung tissue becomes stiff, making it harder for oxygen to move into the bloodstream. People may experience symptoms such as shortness of breath, a dry cough, and ongoing fatigue. In more advanced cases, extensive scarring can lead to permanent lung damage, known as pulmonary fibrosis.
6. NSAIDs
Nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used to relieve pain and reduce swelling in people with sarcoidosis. They can help with joint pain, muscle aches, and general discomfort caused by inflammation. Although they do not treat the underlying cause of sarcoidosis, they can make symptoms easier to manage for many patients.
NSAIDs work by blocking substances in the body that trigger inflammation. This may improve comfort and mobility in mild cases, especially when vital organs are not involved. However, NSAIDs are not a primary treatment for sarcoidosis. When the lungs, heart, or other major organs are affected, stronger medications that suppress immune activity are usually required.
Like all medications, NSAIDs can cause side effects. Common problems include stomach irritation, heartburn, and nausea. Higher doses or combining NSAIDs with blood-thinning medicines can increase the risk of stomach ulcers or bleeding.
7. Etanercept
Etanercept belongs to a group of medications called tumor necrosis factor (TNF) inhibitors. These drugs work by blocking TNF, a protein in the body that plays a key role in inflammation. Researchers are investigating whether TNF inhibitors, such as etanercept, can help manage sarcoidosis.
This is because the condition involves an overactive immune response, especially in cases where standard treatments fail. TNF inhibitors are mainly used to treat autoimmune conditions such as rheumatoid arthritis and psoriatic arthritis. In some people with sarcoidosis, reducing TNF activity may decrease the formation of granulomas.
These are clusters of immune cells that cause inflammation in the lungs, skin, eyes, or other organs. However, the results have been mixed, and TNF blockers are not considered first-line therapy for sarcoidosis. Some studies suggest that TNF inhibitors may be helpful in certain cases, particularly when sarcoidosis affects the eyes or joints.
8. Triggers
Sarcoidosis does not have one single known cause, but several factors may act as triggers that start or worsen inflammation. Exposure to dust, mold, wood smoke, silica, and certain insecticides at home or work increases the risk of sarcoidosis. People in jobs with frequent exposure, such as firefighters, healthcare workers, and construction workers, appear to be affected more often.
Bacteria such as Mycobacterium tuberculosis, Chlamydia pneumoniae, and Propionibacterium species have been studied as possible contributors. Certain viral infections, including those in the herpes family, may also play a role by stimulating an abnormal immune response.
Genetics seems to influence how the immune system reacts to these environmental and infectious agents. People with a family history of sarcoidosis may be more susceptible. The condition is more prevalent in certain ethnic groups and regions, indicating that genetic factors may interact differently with external triggers.
9. Agricultural Activities
People who work in farming are often exposed to dust, soil, and organic materials on a daily basis. These substances can contain particles, microorganisms, and chemicals that may trigger an unusual immune response in some individuals. This response can cause inflammation in the lungs and lymph nodes, which are often affected by sarcoidosis.
Farmers may inhale mold spores that grow in stored hay or grain. While small amounts of exposure do not always cause harm, long-term exposure can increase inflammation in people who are more sensitive. Working with soil and crops can also release natural and man-made particles such as silica and insecticides, which may irritate the lungs and possibly contribute to the development of the disease in susceptible individuals.
Some studies suggest that people who work on poultry, dairy, or crop farms may have a higher risk of sarcoidosis. Repeated exposure to organic dust, plant proteins, and exhaust fumes from farm equipment may overstimulate the immune system. When this immune response does not settle, small clusters of inflamed tissue called granulomas can form and lead to symptoms.
10. Exposure to Certain Industrial Metals
Some studies suggest that exposure to specific industrial metals may play a role in the development of sarcoidosis. People who work in jobs where they inhale metal fumes, dust, or fine particles may have a higher risk of lung inflammation that can trigger the condition. This type of exposure is commonly linked to occupations such as welding, mining, metal manufacturing, and construction.
Metals of concern include beryllium, aluminum, nickel, and materials that contain silica. When these particles are inhaled repeatedly over time, they may cause the immune system to respond abnormally. This reaction can lead to the formation of granulomas, which are small clumps of inflammatory cells that can interfere with normal organ function, especially in the lungs.
11. Construction Work
People who work in construction may face a higher risk of developing sarcoidosis because of ongoing exposure to dust and airborne particles on job sites. Many tasks such as cutting, drilling, and grinding release fine dust that can be inhaled into the lungs. Over time, this repeated irritation may contribute to inflammation and may act as a trigger in people who are more susceptible to the condition.
One major concern in construction work is exposure to silica dust. Silica is found in common materials like concrete, stone, and sand. Inhaling large amounts can damage the lungs. While sarcoidosis is not the same as silicosis, long-term silica exposure may influence the immune system and contribute to the formation of granulomas, which are a hallmark of sarcoidosis.
Construction workers may also be exposed to other substances such as insulation fibers, wood dust, and chemicals used in paints, adhesives, and sealants. Working in enclosed or poorly ventilated areas can increase the concentration of these particles in the air.
12. Mold-Contaminated Environments
Mold commonly grows in damp or poorly ventilated areas such as basements, bathrooms, and water-damaged buildings. People who live or work in these environments may inhale mold spores regularly, often without noticing. Most people aren’t affected by this exposure, but it can cause an inflammatory response in the lungs or other organs in some individuals.
Researchers believe mold exposure could play a role in the development of sarcoidosis in susceptible individuals. Sarcoidosis involves the formation of granulomas, which are small clusters of immune cells. When the immune system overreacts to inhaled particles such as mold spores, this response may lead to inflammation similar to what is seen in the disease.
Exposure tends to be higher in buildings with leaks, poor ventilation, or past flooding. Workplaces with limited air circulation and homes with ongoing dampness can increase the amount of mold in the air. People who spend long hours in these settings may experience repeated irritation due to continuous inhalation of spores.
13. Damaged and Condemned Buildings
Damaged or abandoned buildings can become hidden sources of harmful environmental exposure. Crumbling walls, broken ceilings, and exposed soil may release fine dust and particles into the air. People who live, work, or spend time near these sites may inhale these materials, which can irritate the lungs and potentially trigger inflammation in the body.
These structures often develop mold due to water leaks, flooding, or poor ventilation. Breathing in mold spores can irritate the airways and, in some individuals, may contribute to immune reactions similar to those seen in sarcoidosis. Old paint, insulation, or damaged piping may also contain silica or other inorganic particles that can act as irritants when inhaled. Risk increases during cleanup, renovation, or demolition of condemned buildings when irritants are usually kicked off from the surfaces and into the air.
14. Closed-Air Office Environments
Closed-air office environments may expose workers to poor indoor air quality and tiny airborne particles that can affect lung health. Because sarcoidosis often involves inflammation in the lungs, ongoing exposure to indoor irritants may influence immune responses that trigger the condition in some individuals.
Heating, ventilation, and air conditioning (HVAC) systems can collect dust, mold, and bacteria when they are not properly maintained. These contaminants may circulate throughout the office, increasing exposure to potential irritants. Prolonged contact with particles such as mold spores or inorganic dust may contribute to inflammation in people who are more susceptible.
People who spend long hours in sealed, air-conditioned offices may experience higher levels of indoor pollutants compared to those who work outdoors. Limited air exchange can trap substances such as cleaning chemicals, smoke, and vapors from office furniture or equipment.
