Kyphoscoliotic EDS (kEDS)

ESTIMATED PREVALENCE:  <1 in 1,000,000 [47]  (60 patients worldwide, as of June 9, 2022) [48]

INHERITANCE PATTERN: Autosomal Recessive

SYMPTOMS [49, 50]:

Kyphoscoliotic EDS (kEDS) symptoms consist of congenital muscle hypotonia and/or congenital, early onset of progressive/non-progressive kyphoscoliosis (forward rounding of the back that looks like slouching), osteopenia (low bone mass), osteoporosis (brittle, fragile bones), marfanoid structure and/or chest deformities.  This can be accompanied by hyperextensible skin, skin that is fragile and easily bruises, atrophic (collapsed) scars, fragile sclera/oculus, hernias, rupture or aneurism of certain arteries, joint hypermobility, dysmorphic facial features (such as unusual positioning of eyes/ears or high palate) and additional features.

DIAGNOSTIC CRITERIA [51]:

To diagnose kEDS, the following formula must be satisfied:

Major Criterion #1 + Major Criterion #2 + Major Criterion #3, OR three (3) Minor Criteria

To diagnose kEDS, a patient must have Major Criterion #1 (congenital muscle hypotonia), plus Major Criterion #2 (congenital/early onset of kyphoscoliosis), plus Major Criterion #3 (general joint hypermobility, “GJH”) or three (3) Minor Criteria.  Patients must also satisfy gene-specific criteria, according to the type of kEDS.

There are two main types of kEDS, sometimes called kEDS Type 1 and kEDS Type 2.  These types are aligned with the mutated gene responsible for the specific type of kEDS a patient possesses, PLOD1 (Type 1) or FKBP14 (Type 2). Therefore, molecular genetic testing is required to confirm the diagnosis.

The major and minor criteria and the genetic markers responsible for kEDS:

Major Diagnostic Criteria

  • Congenital muscle hypotonia
  • Congenital or early onset kyphoscoliosis (progressive or non-progressive)
  • GJH with dislocations/subluxations (shoulders, hips, and knees in particular)

Minor Diagnostic Criteria

  • Skin hyperextensibility
  • Easily bruised skin
  • Rupture/aneurysm of a medium-sized artery
  • Osteopenia/osteoporosis
  • Blue sclerae
  • Hernia (umbilical or inguinal)
  • Pectus deformity
  • Marfanoid habitus
  • Talipes equinovarus
  • Refractive errors (myopia, hypermetropia)

Genetic Markers:

PLOD1

FKBP14