Sjögren’s syndrome is a chronic autoimmune disorder characterized by dry eyes and dry mouth. It occurs when the body’s immune system mistakenly attacks its own moisture-producing glands, including the tear and saliva glands. This leads to the hallmark symptoms of Sjögren’s syndrome – dry eyes and dry mouth. However, Sjögren’s syndrome is a systemic disease that can affect the entire body. People with Sjögren’s are at higher risk for developing other autoimmune disorders, infections, and certain types of cancer.
Other Autoimmune Diseases
Sjögren’s syndrome is closely associated with several other autoimmune diseases. This is because the immune system dysregulation that causes Sjögren’s can lead to inflammation and autoantibody production against other parts of the body.
Rheumatoid Arthritis
Rheumatoid arthritis (RA) is one of the most common autoimmune diseases associated with Sjögren’s syndrome. Between 10-30% of people with Sjögren’s also have rheumatoid arthritis. Like Sjögren’s, rheumatoid arthritis is caused by the immune system mistakenly attacking the body’s own tissues, leading to inflammation and joint damage. The joints most often affected are the hands, wrists, and knees. Symptoms of RA include joint pain, stiffness, and swelling.
Systemic Lupus Erythematosus
Systemic lupus erythematosus (SLE) is another autoimmune condition that commonly co-occurs with Sjögren’s syndrome. Estimates suggest 5-10% of Sjögren’s patients also have SLE. In both diseases, the immune system creates antibodies that target the body’s own tissues. SLE can cause inflammation and damage to the joints, skin, kidneys, blood vessels, and other organs. Symptoms include fatigue, joint pain, rash, and fever.
Scleroderma
Scleroderma is a rare autoimmune disease characterized by hardening and tightening of the skin and connective tissues. About 10% of people with Sjögren’s syndrome also have scleroderma. As with other autoimmune conditions, scleroderma is driven by inflammation and antibodies against the body’s own tissues. It primarily affects the skin, blood vessels, and internal organs. Symptoms include thickened skin, swelling, pain, and gastrointestinal issues.
Autoimmune Thyroid Disease
Autoimmune disorders of the thyroid, including Graves’ disease and Hashimoto’s thyroiditis, are more common in people with Sjögren’s syndrome. Up to 10% of Sjögren’s patients also have an autoimmune thyroid condition. With these diseases, the immune system attacks the thyroid gland, leading to either overproduction of thyroid hormone (Graves’) or underproduction (Hashimoto’s). Symptoms include unexplained weight changes, fatigue, and feeling too hot or cold.
Autoimmune Liver Diseases
Some people with Sjögren’s syndrome develop autoimmune inflammation targeting the liver. The two main autoimmune liver diseases are autoimmune hepatitis and primary biliary cholangitis. In autoimmune hepatitis, the immune system attacks and damages liver cells. This can lead to symptoms like fatigue, nausea, abdominal pain, and jaundice. Primary biliary cholangitis causes damage to the bile ducts in the liver, resulting in a buildup of bile. It often causes itching, fatigue, and jaundice. About 5-10% of Sjögren’s patients develop one of these liver conditions.
Myositis
The inflammatory muscle conditions polymyositis and dermatomyositis are more common in people with Sjögren’s syndrome. In these diseases, the immune system attacks the muscles, causing weakness, pain, and rashes. About 5% of people with Sjögren’s will develop myositis. Symptoms include progressive muscle weakness, difficulty swallowing, and a distinctive rash on the eyelids with dermatomyositis.
Lymphoma
One of the most serious complications of Sjögren’s syndrome is an increased risk of developing certain cancers, especially non-Hodgkin lymphoma. The chronic immune system overactivation that occurs with Sjögren’s syndrome seems to increase susceptibility to lymphomagenesis, or lymphoma development.
The most frequently associated lymphomas with Sjögren’s include:
- Marginal zone lymphoma
- Mucosa-associated lymphoid tissue (MALT) lymphoma
- Diffuse large B cell lymphoma
These B cell non-Hodgkin lymphomas arise from lymphocytes located in glands and mucosal tissues, which are often affected in Sjögren’s syndrome. Compared to the general population, people with Sjögren’s syndrome have a nearly 40 times higher risk of developing lymphoma. The lifetime risk is estimated to be about 5%. Sometimes the lymphoma develops from pre-existing benign lymphocytic infiltrates in the salivary glands called pseudolymphomas. Symptoms of lymphoma can include painless swelling of the lymph nodes, fatigue, night sweats, unexplained fevers, and unintentional weight loss.
Regular screening for lymphoma is an important part of managing Sjögren’s syndrome. This typically involves blood tests, imaging, and sometimes lymph node biopsies. Catching lymphoma early greatly improves prognosis and survival.
Infections
Having Sjögren’s syndrome is associated with a higher risk of certain bacterial, viral, and fungal infections. This is thought to be related to both the inherent immune system dysfunction of Sjögren’s and the loss of protective secretions that normally help defend against pathogens.
Some infections more common in Sjögren’s patients include:
- Sinus infections
- Pneumonia
- Bronchitis
- Urinary tract infections
- Yeast infections
- Oral thrush
- Viral infections like the flu
The sinuses, lungs, and urinary tract are all vulnerable targets since they rely on mucus secretions for defense and lubrication. Dryness and inflammation in these areas due to Sjögren’s impairs their protective barriers. Infections should be treated promptly with antibiotics or antifungals as appropriate. Staying up to date on vaccinations is also important for preventing infections.
Kidney Disease
Several types of kidney disease occur more frequently in Sjögren’s syndrome. Inflammation related to Sjögren’s can cause scarring and damage to kidney tubules and filtration units. Interstitial nephritis is one form of kidney inflammation seen in around 10% of Sjögren’s patients.
Kidney tubular acidosis is another disorder that can develop when the renal tubules are damaged. This impairs acid secretion by the kidneys, leading to electrolyte abnormalities and excess acid buildup in the blood. Cryoglobulinemic vasculitis affects the small blood vessels in the kidneys and other organs. It is caused by abnormal inflammatory proteins called cryoglobulins. Symptoms of kidney disease can include fatigue, edema, abnormal kidney function tests, and high blood pressure.
Peripheral Neuropathy
Up to 20% of people with Sjögren’s syndrome develop peripheral neuropathy, or nerve damage in the extremities. This occurs when inflammation damages the peripheral nerves that transmit signals to and from the central nervous system. Peripheral neuropathies associated with Sjögren’s often affect sensation in the hands and feet, causing numbness, tingling, and pain. Sometimes motor nerves are affected too, resulting in muscle weakness and balance problems. Sensory ataxic neuropathy is one form that impairs proprioception, or body spatial awareness.
Raynaud’s Phenomenon
Many Sjögren’s patients develop Raynaud’s phenomenon, which causes discoloration of the fingers and toes in response to cold temperatures or stress. It occurs when blood vessels in the extremities suddenly constrict, limiting circulation. Initially the affected skin turns white, and then blue as it becomes oxygen deprived. As circulation returns, the area becomes flushed and red. Raynaud’s phenomenon can be very painful and increase risk of skin ulcers or tissue damage. It is thought to be related to vascular damage from inflammation.
Hearing Loss and Balance Disorders
Hearing disturbances are common in people with Sjögren’s syndrome, reported in up to 70% of patients. The hearing loss associated with Sjögren’s is usually sensorineural, meaning it arises from damage to the inner ear or auditory nerve. A frequent cause is small fiber vasculitis disrupting the tiny blood vessels supplying the auditory system. The hearing loss often manifests as difficulty understanding speech and amplified sounds.
Vestibular problems affecting balance are also more prevalent with Sjögren’s syndrome. Up to 60% experience dizziness, vertigo, and disequilibrium. Again, this is typically attributed to inflammation-driven damage to the inner ear’s vestibular apparatus. Hearing and balance symptoms in Sjögren’s tend to be progressive, so regular evaluation by an audiologist is recommended.
Gastrointestinal Problems
Gastrointestinal issues are common in Sjögren’s, arising both from mucosal dryness and immune-driven inflammation. Problems can include:
- Dysphagia – Difficulty or painful swallowing
- Gastroparesis – Delayed stomach emptying
- Reflux – Flow of stomach contents back up the esophagus
- Esophageal dysmotility – Disordered muscular contractions in the esophagus
- Atrophic gastritis – Chronic inflammation of the stomach lining
- Pancreatitis – Pancreatic inflammation causing abdominal pain
- Constipation and diarrhea
Many Sjögren’s patients also have celiac disease, an autoimmune reaction to gluten that damages the small intestine. Symptoms of gastrointestinal involvement can include heartburn, indigestion, bloating, nausea, abdominal pain, and changes in bowel habits. Diet modifications, medications, and testing for celiac disease may help manage gastrointestinal symptoms.
Pulmonary Manifestations
Lung issues are more prevalent in Sjögren’s syndrome. Dryness of the airways from lack of protective secretions can cause chronic cough and recurrent respiratory infections. Interstitial lung disease is also seen in about 10% of Sjögren’s patients. Inflammation and scarring damage the lung tissue, interfering with oxygen exchange. This causes progressive shortness of breath.
Other pulmonary complications include tracheobronchial stenosis, or narrowing of the airways, pleural effusions, and shrinking lung syndrome. Pneumonias, bronchitis, and chronic obstructive pulmonary disease tend to be more severe in people with Sjögren’s due to impaired mucociliary clearance. Lung function tests, imaging, and biopsy are used to evaluate respiratory symptoms.
Mental Health Disorders
Neuropsychiatric and cognitive symptoms occur frequently with Sjögren’s syndrome. These include depression, anxiety, brain fog, memory loss, and sleep disturbances. One study found about 30% of Sjögren’s patients experience depression. Fatigue and chronic pain contribute to mood disorders. Inflammation and antibodies targeting brain tissues like the limbic system can also play a role. Evaluating for psychiatric disorders and providing mental health support are important for quality of life with Sjögren’s.
Osteoarthritis
The joints are another common target of increased inflammation in Sjögren’s syndrome. About 15-20% of Sjögren’s patients develop osteoarthritis over time. This degenerative joint disease arises due to cartilage breakdown in the joints. It often affects the knees, hands, hips, and spine. Symptoms include progressive joint pain, swelling, and stiffness. Osteoarthritis treatments aim to alleviate pain and improve joint mobility.
Vasculitis
Vasculitis refers to inflammation targeting the blood vessels. About 5-10% of people with Sjögren’s syndrome have vasculitic manifestations. Small and medium sized blood vessels are most often affected. This can cause damage throughout the body depending on which tissues and organs the vessels supply. Symptoms depend on the vessels involved but may include rash, neuropathy, impaired kidney function, and digital ischemia.
Conclusion
Sjögren’s syndrome significantly increases risk for various other autoimmune, malignant, infectious, neurologic, pulmonary, renal, gastrointestinal, psychological and musculoskeletal disorders. The diversity of associated conditions highlights the systemic nature of Sjögren’s and its ability to impact any part of the body. Screening and prompt treatment of related diseases can help prevent complications and enhance patients’ quality of life. A multidisciplinary approach with good communication between specialists is key for optimal management of Sjögren’s syndrome.