An interventional study of Blood sampling in Ehlers-Danlos Syndromes (EDS), sponsored by Assistance Publique - Hôpitaux de Paris. Not yet recruiting. Open to female participants aged 18 Years to 60 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-10-27.
Sponsored by Assistance Publique - Hôpitaux de Paris · Not applicable, Interventional, and Diagnostic
Thirteen types of EDS have been described based on their clinical manifestations and genetic backgrounds. Their diagnosis relies on personal and family medical history, together with established clinical criteria. A definitive diagnosis can then be confirmed through genetic testing. However, definitive diagnosis of hypermobile Ehlers-Danlos syndrome (hEDS), the most common EDS subtype (>80% of cases), remains impossible because its molecular basis is still unknown.
The diagnosis of hEDS is based on a set of clinical criteria, some of which are subject to examiner interpretation. These criteria have limitations at the extremes of age and in mild or incomplete forms, potentially preventing a formal diagnosis. Patients may consequently experience a diagnostic odyssey and psychological distress, without recognition of their condition or access to appropriate management.
The diagnosis of hEDS is further complicated by the overlap between its clinical manifestations and those of Hypermobility Spectrum Disorders (HSD), which are relatively common in the general population (1-3%). HSD are also characterized by joint hypermobility, which may be complicated by joint instability and pain, but unlike hEDS, they are not associated with tissue fragility. There is therefore an urgent need to identify a reliable, simple, reproducible, and widely accessible diagnostic criterion to establish a diagnosis of hEDS in the large population of hypermobile patients.
Tenascin-X (TN-X) is a glycoprotein involved in the assembly of the ECM. One study showed that TN-X levels were reduced by 35% in 52% of hypermobile patients (9/17) compared with healthy controls. This finding suggests a possible association between serum TN-X levels and hEDS. However, no correlation has yet been investigated.
We hypothesize that serum TN-X levels could serve as a biological diagnostic criterion for hEDS.
66 studies on the registry are indexed under Ehlers-Danlos Syndrome; 24 are open to participants now.
This study's planned enrollment of 80 is above the median of 60 across 32 interventional studies indexed under Ehlers-Danlos Syndrome.
Browse Ehlers-Danlos Syndrome studies →Assistance Publique - Hôpitaux de Paris is the lead sponsor of 3,592 studies on the registry; 1,033 are open to participants now.
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hEDS group:
hEDS diagnostic criteria according to the 2017 classification Female sex Age between 18 and 60 years
Control group = healthy volunteers:
Female sex Age between 18 and 60 years.
Exclusion criteria hEDS group:
Pregnant or breastfeeding women Persons deprived of their liberty or under legal guardianship Persons unable to comply with the medical follow-up required for the study for geographical, social, or psychological reasons Persons not affiliated with the French social security system Inability to provide the participant with adequate information and/or inability of the participant to provide written : dementia, psychosis, impaired consciousness, non-French-speaking patients
Control group = healthy volunteers:
Suspected or diagnosed hEDS Joint hypermobility with a Beighton score ≥ 5 History of recurrent sprains and/or dislocations History of scoliosis requiring bracing or surgery Clinical cutaneous features suggestive of EDS or another connective tissue disorder Connective tissue-related skin disorders (hypertrophic or keloid scars, etc.) Fragility of other connective tissues in the body Diseases or conditions causing extracellular matrix (ECM) remodeling (tumors, inflammatory or allergic diseases, postoperative healing within the previous year) Pregnant or breastfeeding women Persons deprived of their liberty or under legal guardianship Persons unable to comply with the medical follow-up required for the study for geographical, social, or psychological reasons Persons not affiliated with the French social security system Inability to provide the participant with adequate information and/or inability of the participant to provide written informed consent: dementia, psychosis, impaired consciousness, non-French-speaking patients.
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Collection of blood samples (serum and whole blood) during a follow-up visit as part of the participant's usual care for TN-X concentration measurement
Genetic: Blood sampling
Collection of blood samples (serum and whole blood) for TN-X concentration measurement
Genetic: Blood sampling
Collection of blood samples (serum and whole blood) for TN-X concentration measurement
Measurement of TN-X concentration
Measurement of TN-X concentration (ng/mL) in serum from the experimental population (= patients with hypermobile Ehlers-Danlos syndrome \[hEDS\]) and the control population (= healthy volunteers), using a targeted quantitative proteomics approach based on mass spectrometry We will assess the ability of the serum TN-X level to discriminate between patients with and without hEDS, classified according to the gold standard, using the area under the ROC curve, estimated as a point estimate and with a 95% confidence interval. The diagnosis of hEDS, considered the gold standard, will be established according to the clinical criteria validated by the International Consortium on Ehlers-Danlos Syndromes \[4,5\], by a physician with expertise in this rare disease at the participating centers.
Time frame: through study completion, an average of 1 year
Diagnostic threshold for serum TN-X levels for the diagnosis of hEDS
Diagnostic threshold for serum TN-X levels for the diagnosis of hEDS, determined using the Youden index on the same ROC curve.
Time frame: through study completion, an average of 1 year
No study locations are listed for this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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