Langer Saldino syndrome

Langer Saldino syndrome, or achondrogenesis type II is a subtype of achondrogenesis. It is an extremely rare fatal skeletal dysplasia.

Pathology

Genetics

This type of achondrogenesis results from a mutation in the collagen type II gene (COL2A1) on chromosome 12q. That mutation affects type II collagen encoding, resulting in poor or absent type II collagen. Most cases are sporadic, although some may be via autosomal dominant inheritance.

Clinical presentation

Most cases are stillborn or die within a few hours after birth. The neonate is extremely short stature and presents with a large calvarium, large fontanelles, hypertelorism, depressed nasal bridge, anteverted nostrils, hypertrophied tongue and micrognathia. 

Other abnormalities include a short neck, short limbs (rhizomelic), narrow thorax and distended abdomen.

Occasionally other abnormalities such as microtia, cleft palate, polydactyly, and hydrops can be present. Lymphatic malformations have also been described.

Radiographic features

Radiographic features include:

• normal cranial ossification

• short ribs without fracture

• short and broad tubular bones with metaphyseal widening and spurs

• disproportionately long fibula

• squaring of iliac wings with a horizontal acetabular angle

• insufficiently ossified vertebrae, ischium, pubic bone, calcaneum, and talus

Antenatal ultrasound

Prenatal ultrasound makes it possible for early detection of various skeletal dysplasias: as early as 15 to 19 weeks of gestation. Findings may include:

• polyhydramnios

• nuchal edema

• hydrops

• cystic hygroma

• short limbs

• cleft palate

See also

• achondrogenesis

  • type I: 

    • type Ia: Houston-Harris subtype

    • type Ib: Parenti-Fraccaro subtype

  • type II: Langer-Saldino syndrome