The name rheumatoid arthritis, or RA is a bit misleading. This autoimmune disease, where the body’s own immune system attacks its healthy tissues and organs, does involve the joints but can also be systemic. Complications of the disease can involve the heart, the blood vessels, the eyes or the lungs. Besides being an autoimmune disorder, RA is an inflammatory disease that can set up an inflammatory response in these organs and damage them. Doctors do not know what causes RA and do not know why it attacks the lungs and other organs.
RA-ILD
One disease that is caused by RA is rheumatoid arthritis–associated interstitial lung disease. Also called RA-ILD, it inflames and scars the tissue of the lungs. Unlike rheumatoid arthritis itself, which strikes more women than men, men with RA are more at risk for contracting RA-ILD. People who smoke are also more at risk. Doctors still do not know how to effectively treat RA-ILD, and prescription medications seem to bring little relief. Indeed, some drugs seem to make the symptoms worse. When symptoms do appear, they include an unproductive cough and shortness of breath.
Pulmonary Fibrosis
Pulmonary fibrosis is another way that RA attacks the lungs. In this disease, the lung tissue is damaged and eventually grows stiff and thick with scar issue. Like RA-ILD, the patient is short of breath and has a dry cough. They are tired all the time, lose weight without meaning to and suffer from joint and muscle aches. Another symptom of pulmonary fibrosis is that their fingers and toes take on an odd club shape which is common for people with lung problems. Pulmonary fibrosis is not curable as of 2018, and it comes with its own complications including pulmonary hypertension, or high blood pressure in the lungs; cor pulmonale, where one side of the heart fails; lung cancer and respiratory failure. Respiratory failure is the end state of pulmonary fibrosis and happens when the patient can no longer take in enough oxygen.
One ironic cause of pulmonary fibrosis is a drug called methotrexate, which is used to treat RA.
Lung Nodules
People with RA often develop nodules, or bumps beneath their skin. They can be unsightly but don’t hurt or cause other problems unless they are on the soles of the feet. They don’t need treatment. Lung nodules are more benign complications of RA. Some patients don’t discover that they have nodules in their lungs until their lungs are examined for some other problem. RA can also lead to nodules on the person’s vocal cords and in their throat which changes the quality of their voice.
Problems with the Lining of the Lungs
Problems with the pleura, or the lining of the lungs are common in people with rheumatoid arthritis. The pleura is a two layered membrane that covers the lungs and lines the chest wall. When they are inflamed, the layers rub against each other or fluid builds up between the layers. Fortunately, most people are asymptomatic, but some people have pleurisy or pleural effusions.
Pleurisy happens when the pleura are inflamed. The person feels a sudden chest pain that might make them think they're having a heart attack. The pain gets worse when they breathe or cough. The pain can be vague or intense. It’s most often felt in the area of inflammation but can be felt lower down in the chest or even in the patient’s abdomen. The person sometimes has a fever and feels uncomfortable when they move the affected side of the body. The have difficulty breathing and they take in rapid, shallow breaths. Complications of pleurisy include pneumonia and scar tissue in the pleura, which can lead to even more pain and difficulty in breathing. Another complication of pleurisy is pleural effusion.
Pleural effusion happens when fluid collects in the space between the pleura. There is always some fluid between the pleural membranes to lubricate the space and allow the lungs to expand and contract smoothly, but this fluid is abnormal. It can be cloudy or watery. If it contains pus it is called empyema. If it is bloody, it is called a hemothorax. If it has air bubbles, it is called pneumothorax. Milky fluid made up of lymph fluid and fat is called chylothorax.
Some people with mild pleural effusion do not feel pain, and the problem may be discovered when the patient is being treated for other problems with their RA. In other cases, the patient feels pain. As in pleurisy, it may be vague or stabbing and gets worse with coughing or even breathing. They also experience the unproductive cough and shortness of breath of pleurisy. Patients can also suffer from swollen feet and ankles, fever, unexplained weight loss, night sweats and blood in their sputum.
A large effusion may need to be drained through a needle or a tube inserted in the patient’s chest, and they may be prescribed a drug called a fibrinolytic. This drug normally dissolves blood clots but is given for pleural effusion to stop fluid from accumulating. In very severe cases, a doctor may need to perform surgery to take fibrous tissue from the lung.