E2 ModeratePreliminaryPEM not requiredCross-SectionalPeer-reviewedMachine draft
Clinicopathological findings consistent with primary Sjögren's syndrome in a subset of patients diagnosed with chronic fatigue syndrome: preliminary observations.
Sirois, D A, Natelson, B · The Journal of rheumatology · 2001
Quick Summary
Some people with ME/CFS experience dry eyes and dry mouth, which are also common symptoms of Sjögren's syndrome, an autoimmune disorder. This study tested 25 ME/CFS patients and 18 healthy volunteers for signs of Sjögren's syndrome using eye tests, saliva gland biopsies, and blood tests. The researchers found that about one-third of the ME/CFS patients had findings consistent with primary Sjögren's syndrome, while none of the healthy volunteers did.
Why It Matters
This study suggests that a clinically significant subset of ME/CFS patients may have concurrent primary Sjögren's syndrome, which could explain overlapping symptoms like dry eyes and mouth and has implications for diagnosis and treatment. Understanding whether these conditions co-occur or share pathophysiological mechanisms could lead to better targeted management and improved patient care.
Observed Findings
- Mucosal dryness was reported by 52% (13/25) of CFS patients versus an unspecified percentage of controls.
- 32% of CFS patients (8/25) met diagnostic criteria for primary Sjögren's syndrome compared to 0% of controls (p=0.05).
- Low Schirmer test values (reduced tear production) were found in 40% of CFS patients (10/25) versus 6% of controls (1/18, p=0.01).
- Abnormal minor salivary gland biopsy scores were common in both CFS patients (14/25) and controls (15/18).
Inferred Conclusions
- A subset of patients clinically diagnosed with CFS may have primary Sjögren's syndrome as a concurrent or misdiagnosed condition.
- CFS and primary Sjögren's syndrome may share common pathophysiological features or occur together more frequently than expected by chance.
- Lacrimal hyposecretion and salivary gland pathology are more prevalent in CFS patients than in healthy controls.
Remaining Questions
- What is the prevalence of concurrent primary Sjögren's syndrome across larger, more diverse CFS populations?
- Do CFS patients with Sjögren's-like findings have distinct clinical outcomes or treatment responses compared to CFS patients without these findings?
- What specific pathophysiological mechanisms might explain the overlap between CFS and Sjögren's syndrome?
What This Study Does Not Prove
This study does not establish that Sjögren's syndrome causes ME/CFS or vice versa—only that the two conditions may co-occur in some patients. The cross-sectional design cannot establish causality or temporal relationships, and the small sample size limits generalizability to all ME/CFS populations. It also does not determine whether shared pathophysiology exists between the conditions.
Tags
Symptom:Fatigue
Biomarker:Autoantibodies
Method Flag:Weak Case DefinitionSmall SampleExploratory Only
Metadata
- PMID
- 11196514
- Review status
- Machine draft
- Evidence level
- Single-study or moderate support from human research
- Last updated
- 8 April 2026
About the PEM badge: “PEM required” means post-exertional malaise was an explicit required diagnostic criterion for participant inclusion in this study — not that PEM was studied, observed, or discussed. Studies using criteria that do not require PEM (e.g. Fukuda, Oxford) are tagged “PEM not required”. How the atlas works →
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