Jarcho Levin syndrome is a genetic birth defect which causes malformed bones in the spine (vertebrae) and ribs (called spondylothoracic dysostosis). The chest has a distinctive crab-like appearance. Infants born with Jarcho Levin syndrome have difficulty breathing due to their small, malformed chests.

Jarcho Levin syndrome affects both males and females. It is not known exactly how often it occurs.

Symptoms of Jarcho Levin syndrome may include:

  • malformed spine bones (vertebrae) such as fusion of the bones
  • the malformed spine bones cause the spine to curve outward (kyphosis), inward (lordosis), and sideways (scoliosis)
  • the malformed spine bones and abnormal curves make the trunk small and cause short stature
  • some of the ribs are fused together and others are malformed, giving the chest a crab-like appearance
  • the neck is short and has limited motion
  • distinctive facial features and mild cognitive deficit may sometimes occur.

In some infants with Jarcho Levin syndrome there may be other birth defects such as congenital heart defects or defects in the central nervous system and/or genitourinary tract.

Types

In 1968, Dr. David Rimoin and colleagues in Baltimore first distinguished between the two major presentations of Jarcho-Levin. Both conditions were characterized as failures of proper vertebral segmentation. However, the condition within the family described in their article appeared to be inherited in a autosomal dominant fashion and had a less severe course than that reported by other investigators. They specified their condition as spondylocostal dysplasia, which has since become to be known as Spondylocostal Dysostosis. The subtype of Jarcho-Levin with which they contrasted their reported cases to is now known as Spondylothoracic Dysplasia.

Spondylothoracic Dysplasia

Spondylothoracic dysplasia, or STD, has been repeatedly described as an autosomal recessively inherited condition that results in a characteristic fan-like configuration of the ribs with minimal intrinsic rib anomalies. Infants born with this condition typically died early in life due to recurrent respiratory infections and pneumonia due to their restricted thorax. Recently, a report has documented that actual mortality associated with STD is only about 50%, with many survivors leading healthy, independent lives.

Spondylocostal Dysostosis

In contrast to STD, the subtype Spondylocostal dysostosis, or SCD features intrinsic rib anomalies, in addition to vertebral anomalies. Intrinsic rib anomalies include defects such as birfurcation, broadening and fusion that are not directly related to the vertebral anomalies (such as in STD, where extensive posterior rib fusion occurs due to segmentation defects and extreme shortening of the thoracic vertebral column).

Diagnosis

Jarcho Levin syndrome is usually diagnosed in the newborn infant based upon his/her appearance. Although it is known that Jarcho Levin syndrome is associated with a mutation in the DLL3 gene, there is no specific genetic test available for diagnosis.

Treatment

Infants born with Jarcho Levin syndrome have difficulty breathing due to their small, malformed chests, and therefore are prone to repeated respiratory infections (pneumonia).

Babies born with Jarcho-Levin are usually very healthy and grow up to lead normal lives. However, some individuals with Jarcho-Levin suffer from problems of respiratory insufficiency secondary to volume-restricted thoraces. These individuals will often develop pulmonary complications and die in infancy or early childhood. As they grow, the chest is too small to accommodate the growing lungs, and it is difficult for the child to survive beyond the age of two years. Treatment usually consists of intensive medical care, including treatment of respiratory infections and bone surgery.

Source: Wikipedia and About.com