Musculocontractural Ehlers-Danlos Syndrome (mcEDS)

mcEDS is a genetic connective tissue disorder that causes congenital multiple contractures and characteristic craniofacial and skin features.

mcEDS is an ultra-rare disorder that affects less than 1 in 1 million people.

mcEDS is caused by differences in the genes called genetic variants. These genetic variants affect the connective tissue, which provides support, protection, and structure throughout the body.

mcEDS is caused by genetic variants of these genes:

• CHST14 
• DSE 

mcEDS is inherited in an autosomal recessive pattern. This means if a person inherits the genetic variant from both of their parents, they will have mcEDS. People with one copy of the genetic variant are carriers of mcEDS. Carriers do not have the condition themselves but may pass the genetic variant on to their children.

mcEDS may be suspected if a person has:

• Congenital multiple contractures (most commonly, adducted thumbs and clubfoot)
• Characteristic craniofacial features, such as
  • Large fontanelle
  • Large distance between the eyes
  • Short and down-slanting palpebral fissures
  • Blue sclerae
  • Short nose with hypoplastic columella
  • Low-set and rotated ears
  • High palate
  • Long philtrum
  • Thin upper lip vermilion
  • Small mouth
  • Microretrognathia
• Long, tapering, slender, or cylindrical finger shapes
• Fine palmar creases or wrinkles that become more prominent with age
• Progressive talipes deformities
• Spinal deformities (decreased curvature, scoliosis, or kyphoscoliosis)
• Skin hyperextensibility
• Skin fragility
• Atrophic scarring
• Easy bruising
• Recurrent large subcutaneous hematomas
• Delayed motor development
• Muscle hypotonia and weakness
• Joint dislocations
• Pectus deformities

If a person meets the diagnostic criteria for mcEDS, genetic testing should be done to confirm the diagnosis. Genetic testing is used to see if a person has the genetic variants that cause mcEDS.

To meet the diagnostic criteria for mcEDS at birth or in early childhood, a person must meet major criterion 1 AND major criterion 2

To meet the diagnostic criteria for mcEDS in adolescence and adulthood, a person must meet major criterion 1 AND major criterion 3

Major Criteria

1. Congenital multiple contractures, characteristically adduction-flexion contractures and/or talipes equinovarus (clubfoot)
2. Characteristic craniofacial features, which are evident at birth or in early infancy
3. Characteristic cutaneous features including skin hyperextensibility, easy bruisability, skin fragility with atrophic scars, increased palmar wrinkling

Minor Criteria

1. Recurrent/chronic dislocations
2. Pectus deformities (flat, excavated)
3. Spinal deformities (scoliosis, kyphoscoliosis)
4. Peculiar fingers (tapering, slender, cylindrical)
5. Progressive talipes deformities (valgus, planus, cavum)
6. Large subcutaneous hematomas
7. Chronic constipation
8. Colonic diverticula
9. Pneumothorax/ pneumohemothorax
10. Nephrolithiasis/cystolithiasis
11. Hydronephrosis
12. Cryptorchidism in males
13. Strabismus
14. Refractive errors (myopia, astigmatism)
15. Glaucoma/elevated intraocular pressure

mcEDS is managed by addressing the symptoms a person is experiencing. mcEDS can cause a variety of symptoms in many different areas of the body, so people with mcEDS may require multiple providers in different specialties to manage their care. Key aspects of care focus on managing musculoskeletal and skin problems and monitoring for issues with the cardiovascular, ocular, auditory, and renal systems. Each person should work with their care team to develop a care plan that meets their individual needs.

Resources

The Ehlers-Danlos Syndromes, Rare Types 

The 2017 International Classification of the Ehlers-Danlos Syndromes