Yes, Autoimmune Conditions Can Present with Features Resembling EDS Hypermobility
Several autoimmune and rheumatological conditions can mimic or coexist with hypermobile Ehlers-Danlos syndrome (hEDS), and emerging evidence suggests a possible autoimmune component to hEDS itself. 1
Key Autoimmune Conditions That Resemble hEDS
Rheumatological Overlap
Patients with hEDS show significantly increased associations with multiple autoimmune rheumatological conditions 2:
- Ankylosing spondylitis - HLA-B27 antigen prevalence is 23.9% in hEDS patients versus 6.1% in the general U.S. population (p < 2.2 × 10⁻⁸)
- Rheumatoid arthritis - presents with joint pain and can mimic hypermobility symptoms
- Psoriasis and psoriatic arthritis - associated with joint manifestations
- Fibromyalgia - frequently overlaps with hEDS presentation
The percentage of patients with at least one rheumatological condition correlates directly with workup intensity: 9.2% with physical exam only, 33.3% with limited workup, and 67.1% with comprehensive workup 2.
Emerging Autoimmune Mechanisms in hEDS
Recent evidence demonstrates a possible autoimmune dysfunction role in the pathogenesis of hEDS, POTS (postural orthostatic tachycardia syndrome), and MCAS (mast cell activation syndrome). 1 This includes:
- Increased prevalence of autoimmune diseases in POTS patients
- Greater likelihood of autoimmune disease in family members
- Increased frequency of nonspecific autoantibodies
- Presence of autoantibodies to adrenergic and muscarinic receptors, antinuclear antibody, Sjögren's antibodies, and antibodies to norepinephrine, acetylcholine, and angiotensin II 1
Critical Diagnostic Pitfall: The Exclusion Requirement
Genetic testing identified alternative or additional diagnoses in 26.4% of patients who initially met 2017 hEDS criteria, with clinical implications requiring distinct management strategies. 3 This underscores that:
- Hypermobility may be a shared phenotype across inflammatory diseases, monogenic syndromes, and chromosomal abnormalities
- The third diagnostic criterion for hEDS—exclusion of alternative diagnoses—is critically important but underutilized
- Genetic testing plays an essential role in distinguishing true hEDS from autoimmune mimics
Practical Clinical Approach
When to Suspect Autoimmune Overlap
Consider comprehensive rheumatological workup when patients present with:
- Joint hypermobility PLUS inflammatory markers (elevated ESR/CRP)
- Morning stiffness lasting >30 minutes (suggests inflammatory arthritis)
- Symmetric joint involvement (suggests RA)
- Skin manifestations (psoriasis, photosensitivity, rashes)
- Positive family history of autoimmune disease
- Systemic symptoms (fever, weight loss, fatigue beyond typical hEDS)
Recommended Workup Strategy
For patients with suspected hEDS and concerning features 2:
- Inflammatory markers: ESR, CRP
- Autoantibody panel: ANA, RF, anti-CCP, HLA-B27
- Imaging: X-rays to assess for erosive changes (absent in pure hEDS)
- Genetic testing: To exclude alternative diagnoses 3
Management Implications
Left untreated, coexisting autoimmune conditions can contribute to pain or physical disability (including joint erosions) in patients initially diagnosed with hEDS. 2 These conditions require different clinical management strategies:
- Autoimmune arthritis: Disease-modifying antirheumatic drugs (DMARDs), biologics
- Pure hEDS: Physical therapy, joint protection, pain management without immunosuppression
Important Caveat
The association between hEDS and autoimmune conditions works bidirectionally—patients with established autoimmune diseases may also have genuine joint hypermobility that complicates their presentation. Up to 40% of POTS patients report a viral infection as the precipitating event, suggesting post-infectious autoimmune mechanisms 1. This is particularly relevant given associations between COVID-19 and both POTS and hEDS-like presentations.
The key clinical takeaway: Do not assume all hypermobility in the context of systemic symptoms is hEDS—comprehensive workup is essential to identify treatable autoimmune conditions that require fundamentally different therapeutic approaches. 2, 3