Short rib–polydactyly syndrome

A rare genetic disorder characterized by skeletal abnormalities and polydactyly

Short rib–polydactyly syndrome
Synonyms	N/A
Pronounce	N/A
Specialty	N/A
Symptoms	Short ribs, polydactyly, skeletal dysplasia
Complications	N/A
Onset	Congenital
Duration	Lifelong
Types	N/A
Causes	Genetic mutations
Risks	N/A
Diagnosis	Prenatal diagnosis, genetic testing
Differential diagnosis	N/A
Prevention	N/A
Treatment	Symptomatic and supportive
Medication	N/A
Prognosis	Variable
Frequency	N/A
Deaths	N/A

Short rib–polydactyly syndrome (SRPS) is a group of rare, inherited autosomal recessive disorders characterized by the presence of short ribs, polydactyly (extra fingers or toes), and other skeletal abnormalities. These syndromes are part of a broader category of conditions known as skeletal dysplasias, which affect the development of bone and cartilage.

Classification

Short rib–polydactyly syndrome is classified into several types based on clinical features and genetic findings. The main types include:

• Type I (Saldino-Noonan syndrome)
• Type II (Majewski syndrome)
• Type III (Verma-Naumoff syndrome)
• Type IV (Beemer-Langer syndrome)

Each type has distinct clinical features, but all share the common characteristics of short ribs and polydactyly.

Genetics

SRPS is caused by mutations in genes that are involved in the development of the cilia, which are hair-like structures on the surface of cells. These genes include IFT80, DYNC2H1, and WDR34, among others. The inheritance pattern is autosomal recessive, meaning that an affected individual must inherit two copies of the mutated gene, one from each parent.

Clinical Features

The primary features of SRPS include:

• Short ribs: This leads to a narrow chest, which can cause respiratory distress in newborns.
• Polydactyly: Extra fingers or toes, which can be preaxial (on the thumb side) or postaxial (on the little finger side).
• Skeletal abnormalities: These may include limb shortening, narrow thorax, and pelvic dysplasia.
• Other anomalies: Some types of SRPS may also present with renal cysts, congenital heart defects, and cleft lip and palate.

Diagnosis

Diagnosis of SRPS is typically made through a combination of clinical evaluation, imaging studies such as X-rays and ultrasound, and genetic testing. Prenatal diagnosis is possible through ultrasound and genetic testing if there is a known family history of the condition.

Management

There is no cure for SRPS, and treatment is primarily supportive. Management may include:

• Respiratory support: Due to the narrow chest and potential respiratory distress.
• Surgical interventions: To correct polydactyly or other skeletal deformities.
• Multidisciplinary care: Involving specialists in genetics, orthopedics, pulmonology, and other fields as needed.

Prognosis

The prognosis for individuals with SRPS varies depending on the type and severity of the condition. Some forms are lethal in the perinatal period, while others may allow for survival into childhood or beyond with appropriate medical care.

Also see

• Skeletal dysplasia
• Polydactyly
• Ciliopathy
• Autosomal recessive disorder