Medical Zebras

When you hear hoofbeats, think zebras, not horses

Ehlers-Danlos Syndrome(EDS) is characterized by a weakness of the body's connective tissues. Connective tissues act like "glue" in the human body, holding everything together. Collagen, a protein that adds strength to the connective tissues, is not produced correctly in an individual with EDS. The resulting weak connective tissues are too weak to hold the organs, ligaments, joints, ect. of the body in place.

Ehlers-Danlos Syndrome is currently separated into 6 major types. Individuals may have a combination of several of these types.

 

Hypermobility Type

 

                                                                              Quick Identification

Symptoms: Hyperflexibility of the large and small joints, hyperextensibility of the skin, chronic joint pain, smooth and/or velvety skin, easy bruising, and/or recurring joint subluxations and dislocations

Diagnosis: Symptoms and family history may be used in diagnosis. 

Pathology: No specific biochemical collagen finding has been identified. Inherited in an autosomal dominant manner

 

Classical Type

 

                                                                             Quick Identification

Symptoms: Skin hyperextensibility, joint hyperflexibility, widened, atrophic scars, easy bruising, smooth and/or velvety skin, tissue fragility, recurrent joint subluxations and dislocations, pes planus, muscle hypotonia, delayed gross motor function development, hiatal hernia, cervical insufficiency, prolapse in childhood, and/or mulluscoid psuedo tumors (calcified hematomas) associated with scars

Diagnosis:  Symptoms and family history may be used in diagnosis. 

Pathology: Abnormal electrophoretic mobility of the proa1(V) or proa2(V) chains of collagen type V has been detected in some but not all patients. Inherited in an autosomal dominant manner.

 

 Vascular Type

 

                                                                             Quick Identification

Symptoms: Thin and translucent skin, certain facial characteristics (large eyes, thin nose, ears without lobes, short stature, and thin scalp hair), hypermobility of the digits, visual decrease in subcutaneous tissue in the face and extremities, extensive bleeding as a result of minor trauma, complications during and after surgery, early onset varicose veins, talipes equinovarus seen at birth,, acrogeria (premature aging of the skin), artiovenusfistula, carotidcavernousfistula, gingivalverecession, pneumothorax, pneumothemothorax, and/or spontaneous arterial, intestinal, tendon, muscle, or uterine rupture

Diagnosis: A skin biopsy can be used to diagnose this condition. Symptoms and family history may also aid in diagnosis.

Pathology: Structural defects in the proa1(III) chain of collagen type III encodes by COL3A1. Inherited in an autosomal dominant manner.

 

 Kyphoscoliosis Type

 

                                                                              Quick Identification

Symptoms: Easy bruising, atrophic scars, generalized joint laxity and severe muscle hypotonia at birth that leads to delayed gross motor development, Scoliosis at birth that is progressive, spontaneous arterial rupture, marfanoid habitus (Marfan-like features), micro cornea, and/or radiologically considerable osteopenia (diminished amount of bone tissue)

Diagnosis: A urine test may be used to diagnose this condition. Symptoms and family history may also aid diagnosis.

Pathology: Deficiency of the collagen-modifying enzyme lysylhydroxylase (PLOD). Inherited in an autosomal recessive manner.

 

Arthrochalasia Type

 

                                                                             Quick Identification

Diagnosis: A skin biopsy may be used to diagnose this condition. Symptoms and family history may also aid  diagnosis.

Pathology: Mutations leading to deficient processing of the amino-terminal end of proa1(I) [type A] or proa2(I)[type B] chains of collagen type I. Inherited in an autosomal dominant manner.

 

Dermatosparaxis Type 

 

                                                                             Quick Identification

Diagnosis: A skin biopsy may be used to diagnose this condition. Symptoms and family history may also aid diagnosis.

Pathology: Deficiency of procollagenI N-terminal peptidase. Inherited in an autosomal recessive manner.