Acrocallosal syndrome- Schinzel type

Synonyms

Schinzel syndrome 1
Acrocallosal syndrome
ACS
Schinzel acrocallosal syndrome
Absence of corpus callosum with unusual facial appearance, mental deficiency, duplication of the halluces and polydactyly
ACLS

Overview

Acrocallosal syndrome is a rare autosomal recessive syndrome characterized by corpus callosum agenesis, polydactyly, multiple dysmorphic features, motor and mental retardation, and other symptoms. The syndrome was first described by Albert Schinzel in 1979. It is associated with GLI3.

Symptoms

  • Mental retardation
  • Seizures
  • Enlarged head
  • Widely spaced eyes
  • Cleft lip
  • Schinzel Type ACS Hallux Duplication
  • Aplasia/Hypoplasia of the corpus callosum
  • Cognitive impairment
  • Duplication of phalanx of hallux
  • Duplication of thumb phalanx
  • Hypertelorism
  • Macrocephaly
  • Postaxial foot polydactyly
  • Postaxial hand polydactyly
  • Preaxial foot polydactyly
  • Preaxial hand polydactyly

Causes

It has been reported in the literature that acrocallosal syndrome, Schinyel type is a classic genetic disease and it is product of interaction of two genes. Both genes are inherited from mother and father. There are also cases in which no family history of this disorder and it may be the result of unknown genetic mutations.

Prevention

Antenatal diagnosis is possible for better prevention of this genetic disorder. Acrocallosal syndrome should be suspected in any child with polysyndactyly, absence of corpus Callosum, mental retardation and hypotonia.

Diagnosis

In families with members previously diagnosed with the disorder, acrocallosal syndrome, Schinzel type may be suspected before birth (prenatally) based upon certain specialized tests, which are ultrasound or fetoscopy. Fetal ultrasonography is a noninvasive diagnostic procedure in which reflected sound waves create an image of the developing fetus. During fetoscopy, a flexible, ultrasound-guided, viewing instrument is introduced into the uterus through the abdominal wall to directly observe the fetus.

The diagnosis is usually made or confirmed at birth based upon a thorough clinical examination, identification of characteristic physical findings, and various specialized tests. Such testing may include x-ray studies; advanced imaging techniques, such as computed tomography (CT) scanning or magnetic resonance imaging (MRI); or other studies to help detect or characterize certain malformations that may be associated with the disorder (e.g., agenesis or hypoplasia of the corpus callosum, certain craniofacial abnormalities, polydactyly and syndactyly, etc.). During CT scanning, a computer and x-rays are used to create a film showing cross-sectional images of internal structures. MRI uses a magnetic field and radio waves to create detailed cross-sectional images of certain organs and tissues.

A thorough cardiac evaluation may also be recommended to detect any heart abnormalities that may be associated with the disorder. Such evaluation may include a thorough clinical examination, during which heart and lung sounds are evaluated through use of a stethoscope, and specialized tests that enable physicians to assess the structure and function of the heart (e.g., x-ray studies, electrocardiography, echocardiography, cardiac catheterization).

Prognosis

Prognosis is dependent on the degree of hypotonia and early onset of epilepsy rather than the degree of craniofacial and limbs malformations. Neonatal respiratory distress & intercurrent infections are the leading cause of early death in these children.

Treatment

The treatment of acrocallosal syndrome, Schinzel type is directed toward the specific symptoms that are apparent in each individual. Such treatment may require the coordinated efforts of a team of medical professionals, such as pediatricians; surgeons; physicians who diagnose and treat neurological disorders (neurologists); physicians who specialize in heart disease (cardiologists); physicians who diagnose and treat disorders of the skeleton, joints, muscles, and related tissues (orthopedists); eye specialists; and/or other health care professionals.

Resources

  • NIH