Depending on the location of the exostoses they cause numerous complications such as compression of the spinal cord, asymmetric growth of the limbs and reduced mobility.Langer–Giedion syndrome initially causes joint hypermobility. This progresses to joint stiffness later in life when osteochondromas begin to develop, typically between infancy and mid-childhood, which decreases mobility. Hip dysplasia may be present, usually developing in early adulthood although it can occur in infancy or childhood. Skin, hair, sweat glands and nails
Ectodermal dysplasia is a key feature of Langer–Giedion syndrome.The majority of individuals with Langer–Giedion syndrome have sparse scalp hair; this is particularly severe in males, who often experience alopecia shortly after puberty. Despite this the eyebrows may be unusually thick. Cause
The syndrome occurs when a small piece of chromosome 8s long arm, which contains a number of genes, is missing. The loss of these genes is responsible for some of the overall characteristics of Langer–Giedion syndrome.The missing portion of the chromosome is 8q23.2–q24.1. This region includes the genes TRPS1 and EXT1. Diagnosis
Diagnosis is based on clinical findings and can be confirmed by cytogenetic testing, when the deletion is in an average of 5 Mb (millions of base pairs). Nowadays, it is a common practice to run an aCGH (array chromosome hybridization genome) study on peripheral blood of the patient, in order to delineate the extent of the loss of the genomic area, and the deleted genes. Treatment
While no genetic syndrome is capable of being cured, treatments are available for some symptoms. External fixators have been used for limbic and facial reconstructions.
Interrupted aortic arch is a very rare heart defect (affecting 3 per million live births) in which the aorta is not completely developed. There is a gap between the ascending and descending thoracic aorta. In a sense it is the complete form of a coarctation of the aorta. Almost all patients also have other cardiac anomalies, including a ventricular septal defect (VSD), aorto-pulmonary window, and truncus arteriosus. There are three types of interrupted aortic arch, with type B being the most common. Interrupted aortic arch (especially Type B) is often associated with DiGeorge syndrome. Signs and symptoms
Patients with an interrupted aortic arch usually have symptoms from birth, with nearly all presenting symptoms within two weeks (when the ductus arteriosus is usually closed). Causes
It is thought that an interrupted aortic arch occurs through excessive apoptosis in the developing, embryonic aorta. Around 50% of patients have DiGeorge syndrome. Diagnosis
It can be diagnosed with a standard echocardiogram. An echocardiogram can also aid in classifying the type of defect. The diagnosis can also be made prior to birth via ultrasound. Patients will have a loss of appetite, appear tired and weak, and exhibit rapid breathing and a rapid heart rate. If the condition progresses, the infant may turn pale, feel cold in the lower half of the body, and have a weak pulse due to insufficient blood flow.