Stickler syndrome, type 1

Stickler Syndrome, Type 1

Stickler syndrome, type 1, is a genetic disorder that affects connective tissue, primarily impacting the eyes, ears, skeleton, and joints. It is the most common form of Stickler syndrome, a group of hereditary conditions characterized by distinctive facial features, eye abnormalities, hearing loss, and joint problems.

Genetics

Stickler syndrome, type 1, is caused by mutations in the COL2A1 gene, which provides instructions for making a component of type II collagen. This type of collagen is essential for the normal development of connective tissues found in the eyes, ears, and joints. The condition is inherited in an autosomal dominant pattern, meaning one copy of the altered gene in each cell is sufficient to cause the disorder.

Clinical Features

Individuals with Stickler syndrome, type 1, often present with a combination of the following features:

Ocular Abnormalities

- Myopia: Severe nearsightedness is common and often presents in early childhood. - Vitreoretinal degeneration: This can lead to retinal detachment, a serious condition that can result in vision loss if not treated promptly. - Cataracts: Clouding of the lens of the eye may occur, often requiring surgical intervention.

Auditory Abnormalities

- Hearing loss: Sensorineural hearing loss is common and can range from mild to severe. It often affects high-frequency sounds.

Skeletal and Joint Abnormalities

- Joint hypermobility: Increased flexibility of the joints can lead to early-onset arthritis. - Spondyloepiphyseal dysplasia: Abnormal development of the vertebrae and epiphyses can result in short stature and other skeletal issues.

Craniofacial Abnormalities

- Pierre Robin sequence: A combination of a small lower jaw (micrognathia), a tongue that is placed further back than normal (glossoptosis), and cleft palate. - Flat facial profile: Due to underdevelopment of the midface.

Diagnosis

Diagnosis of Stickler syndrome, type 1, is based on clinical evaluation, family history, and genetic testing to identify mutations in the COL2A1 gene. Ophthalmologic, audiologic, and orthopedic assessments are crucial for a comprehensive evaluation.

Management

Management of Stickler syndrome, type 1, is symptomatic and supportive. It may include: - Regular eye examinations: To monitor and treat myopia, cataracts, and prevent retinal detachment. - Hearing aids: To address hearing loss. - Orthopedic interventions: Physical therapy and, in some cases, surgery to manage joint problems. - Speech therapy and surgical interventions: For cleft palate and associated speech difficulties.

Prognosis

The prognosis for individuals with Stickler syndrome, type 1, varies depending on the severity of symptoms and the effectiveness of management strategies. Early diagnosis and intervention can improve quality of life and prevent complications.

Also see

- Stickler syndrome - Collagenopathy, types II and XI - Pierre Robin sequence - Retinal detachment