From the Guidelines
Yes, patients with neuromyelitis optica (NMO) should be worked up for other autoimmune diseases. NMO patients have a significantly higher prevalence of coexisting autoimmune disorders compared to the general population, with approximately 20-30% having at least one additional autoimmune condition. The most common associated autoimmune diseases include systemic lupus erythematosus, Sjögren's syndrome, myasthenia gravis, autoimmune thyroid diseases (particularly Hashimoto's thyroiditis), and rheumatoid arthritis. This association exists because NMO is an autoimmune astrocytopathy mediated by antibodies against aquaporin-4 water channels, and patients with one autoimmune disorder are genetically and immunologically predisposed to developing others.
Key Considerations
- A comprehensive autoimmune workup should include antinuclear antibody (ANA), anti-SSA/SSB antibodies, thyroid function tests with thyroid antibodies, rheumatoid factor, anti-CCP antibodies, and other relevant serological markers based on clinical presentation 1.
- Identifying coexisting autoimmune conditions is crucial for proper management as it may influence treatment decisions, particularly regarding immunosuppressive therapy selection, and can help prevent complications from untreated autoimmune diseases that could worsen the patient's overall prognosis.
- Patients with Sjögren’s syndrome, whether they have secondary autoimmune disease or not, should be comanaged with a rheumatologist owing to the many possible comorbid systemic conditions 1.
Autoimmune Disease Associations
- Systemic lupus erythematosus
- Sjögren's syndrome
- Myasthenia gravis
- Autoimmune thyroid diseases (particularly Hashimoto's thyroiditis)
- Rheumatoid arthritis
Diagnostic Approach
- Antinuclear antibody (ANA)
- Anti-SSA/SSB antibodies
- Thyroid function tests with thyroid antibodies
- Rheumatoid factor
- Anti-CCP antibodies
- Other relevant serological markers based on clinical presentation
Management Implications
- Influence treatment decisions, particularly regarding immunosuppressive therapy selection
- Prevent complications from untreated autoimmune diseases that could worsen the patient's overall prognosis
- Comanagement with a rheumatologist for patients with Sjögren’s syndrome or other systemic autoimmune diseases.
From the Research
Association with Autoimmune Diseases
- Patients with Neuromyelitis Optica (NMO) often have an associated systemic autoimmune disease, most commonly systemic lupus erythematosus (SLE) or Sjogren syndrome (SS) 2, 3, 4, 5.
- The coexistence of NMO and SLE can pose a therapeutic challenge, and it is essential to recognize this possible association 2, 4, 5.
Diagnostic Considerations
- The presence of antibodies against aquaporin-4 (AQP4-IgG) is a specific serological marker for NMO spectrum disorder (NMOSD) 3, 4, 6.
- Patients with NMOSD may have non-organ-specific autoantibodies, which can indicate an underlying autoimmune disease 2, 3.
- A thorough workup, including testing for antinuclear antibodies (ANA) and other autoantibodies, may be necessary to diagnose coexisting autoimmune diseases 4.
Clinical Implications
- The association between NMOSD and autoimmune diseases highlights the importance of considering a broader differential diagnosis in patients with NMO or NMOSD 3, 5.
- Recognizing the coexistence of NMOSD and autoimmune diseases can inform treatment decisions and improve patient outcomes 2, 4, 5.
- Further research is needed to understand the relationship between NMOSD and autoimmune diseases, as well as to develop effective therapeutic strategies for patients with coexisting conditions 6.