About camptomelic syndrome, long-limb type
What is camptomelic syndrome, long-limb type?
Camptomelic syndrome is a rare congenital disorder in which multiple anomalies are present. It is characterized by bowing and angular shape of the long bones of the legs, especially the tibia; multiple minor anomalies of the face; cleft palate; other skeletal anomalies such as abnormalities of the shoulder and pelvic area and eleven pairs of ribs instead of the usual twelve; underdevelopment of the trachea; developmental delay in some cases and incomplete development of genitalia in males such that they appear to be females.
What are the symptoms for camptomelic syndrome, long-limb type?
Campomelic syndrome is a rare form of Skeletal dysplasia characterized by bowing and an angular shape of the long bones of the legs. Eleven sets of ribs instead of the usual twelve may be present. The pelvis and shoulder blade may be underdeveloped. The skull may be large, long and narrow. The face may appear flat with forward tilting nostrils, high forehead, small chin, and cleft palate. Babies may regurgitate formula through the nose, are susceptible to middle ear infections and frequently experience respiratory distress.
Respiratory distress due to an underdeveloped ribcage is the most serious symptom of campomelic syndrome. The lungs may not have sufficient space to grow properly due to the underdeveloped ribcage.
Other symptoms that may occur in some patients with campomelic syndrome are dislocated hips, clubfoot, underdeveloped lungs, abnormal cervical and thoracic vertebrae,and heart and kidney abnormalities.
Some individuals with campomelic syndrome have sex reversal in which they are chromosomally male but have female genitalia and reproductive system.
What are the causes for camptomelic syndrome, long-limb type?
Campomelic syndrome was once thought to be inherited as an autosomal recessive genetic trait but this is no longer thought to be true. Molecular genetic research has shown that a change (mutation) in a single copy of the SOX9 gene on chromosome 17 or disturbance in the regulation of this gene causes campomelic syndrome. The regulation of the SOX9 gene is sometimes disturbed by a rearrangement of genes on chromosome 17 (translocation). It is now believed that campomelic syndrome is inherited as an autosomal dominant trait. Some families have been reported in which multiple children are affected but both parents are unaffected. This may be due to one parent having a mixture of sperm or egg cells with normal and abnormal SOX9 genes (gonadal mosaicism). As a result, one or more of this parent’s children may inherit the gene mutation and exhibit the disorder even though the parent has no apparent symptoms.
Genetic diseases are determined by the combination of genes for a particular trait that are on the chromosomes received from the father and the mother.
Recessive genetic disorders occur when an individual inherits the same abnormal gene for the same trait from each parent. If an individual receives one normal gene and one gene for the disease, the person will be a carrier for the disease, but usually will not show symptoms. The risk for two carrier parents to both pass the defective gene and, therefore, have an affected child is 25% with each pregnancy. The risk to have a child who is a carrier like the parents is 50% with each pregnancy. The chance for a child to receive normal genes from both parents and be genetically normal for that particular trait is 25%. The risk is the same for males and females.
Dominant genetic disorders occur when only a single copy of an abnormal gene is necessary for the appearance of the disease. The abnormal gene can be inherited from either parent, or can be the result of a new mutation (gene change) in the affected individual. The risk of passing the abnormal gene from affected parent to offspring is 50% for each pregnancy regardless of the sex of the resulting child.
What are the treatments for camptomelic syndrome, long-limb type?
Treatment of respiratory problems consists of mechanical or physical breathing assistance such as positive end expiratory pressure (PEEP). Orthopedic medical care including surgery may help alleviate some of the more serious bone deformities. The bowed tibiae usually straighten spontaneously.
It may be appropriate to reassign the sex of a male with female genitalia to be female.
Genetic counseling may be of benefit for patients and their families. Other treatment is symptomatic and supportive.
The Vertical Expandable Prosthetic Titanium Rib (VEPTR) was approved by the FDA in 2004 as a treatment for thoracic insufficiency syndrome (TIS) in pediatric patients. TIS is a congenital condition where severe deformities of the chest, spine, and ribs prevent normal breathing and lung development. The VEPTR is an implanted, expandable device that helps straighten the spine and separate ribs so that the lungs can grow and fill with enough air to breathe. The length of the device can be adjusted as the patient grows. The titanium rib was developed at the University of Texas Health Science Center in San Antonio.
What are the risk factors for camptomelic syndrome, long-limb type?
Camptomelic syndrome, long-limb type is a rare genetic disorder that affects your child's growth and development. The cause of camptomelic syndrome, long-limb type is unknown. Researchers believe that the condition may be related to mutations in the gene that causes cartilage development. These mutations are passed down from parents to their children through genes on chromosomes 6 and 11. Camptomelic syndrome, long-limb type affects both males and females equally. Children with camptomelic syndrome, long-limb type are usually born healthy and normal in size and weight. However, they develop short stature as they grow older due to their shortened limbs. The average height of adults with camptomelic syndrome, long-limb type is between 4' 9" and 5' 2". Children with camptomelic syndrome, long-limb type may have other physical characteristics such as: * A flat face with a broad nose * Eyes that slant upward ( epicanthal folds ) * A short neck with prominent muscles at the base of the neck ( cervical ribs ) The risk factors for Camptomelic syndrome include: 1. The condition is usually caused by a genetic mutation. 2. The syndrome tends to run in families, but it can also occur as a spontaneous mutation. 3. Camptomelic syndrome, long-limb type can be diagnosed with an X-ray, which will show abnormal bone growth in the wrist and ankle area. 4. People with camptomelic syndrome, long-limb type often have low muscle tone (hypotonia), which means they are weak or floppy when they are born, and they tend to develop slowly compared to other children their age. 5. Camptomelic syndrome, long-limb type can also cause intellectual disability and epilepsy in some cases because the brain is not fully developed during infancy (which is when the disease begins).