What is Desbuquois Syndrome?
Desbuquois Syndrome (DBQD) is a very rare condition and type of osteochondrodysplasia. Osteochondrodysplasia refers to a disorder related to the development of the bones and cartilage. Its characteristics may vary according to its severity in the person suffering from it. Some of its characteristics include kyphoscoliosis, osteopenia, and severe joint laxity along with dislocations, distinctive facial characteristics, short extremities, and severe micro malic dwarfism.
There are two types of Desbuquois Syndrome. They are named as Type 1 and Type 2. Type 1 is based on the presence of characteristic hand anomalies, whereas Type 2 is based on the absence of characteristic hand anomalies.
7 patients from Korea and Japan who were suffering from Desbuquois Syndrome have shown a variant form of the syndrome. Its characteristics are minor or joint facial anomalies, and, short stature along with long fingers, significant hand anomalies with short bones in the hand, and advanced bone age.
It is usually inherited in an autosomal recessive manner. Its age of onset is neonatal and antenatal. Genetic counseling is recommended for the person as the transmission of the syndrome is autosomal recessive.
Statistics of the Desbuquois Syndrome
Desbuquois Syndrome is a very rare type of syndrome and a congenital disorder. The symptoms of the disorder may start reflecting at the time of the birth of the child. Both males and females are affected by Desbuquois Syndrome. Worldwide, individuals of both ethnic and racial groups may be affected almost equally. The Kim variant of Desbuquois Syndrome is reported among the people living in Korea and Japan.
Causes of the Desbuquois Syndrome
Reason of Kim variant and Desbuquois Syndrome Type 1 are mutations in the gene named CANT1. The function of a gene called CANT1 is still unknown and it is located on chromosome 17q25.3. Type 1 Desbuquosis Syndrome is usually associated and can be a reason for some of the severe respiratory problems.
There are some of the cases of Type 2 Desbuquois Syndrome which were caused by the mutations in the gene XYLT1 (16p12). XYLT1 encodes xylosyltransferase 1 and is involved in the proteoglycan synthesis and is located on chromosome 16p12. The reason for some of the cases of Type 2 Desbuquois Syndrome is still unknown. It is also suggested that there can be other genes also which are not identified till date but can cause Desbuquois Syndrome.
Symptoms and Signs of the Desbuquois Syndrome
There are several signs and symptoms of Desbuquois Syndrome and they may vary according to their severity and in their type. These symptoms and signs may include:
- Some adults may face obesity.
- Intellectual disability (vary according to various degrees)
- Intrauterine growth retardation
- Generalized joint laxity causing joint dislocations.
- Short stature with shortened extremities may be faced by the patient. Usually, the stature of adults is of or more than 114 cm.
- Significant facial characteristics may be there in some of the patients. Prominent eyes, round flat face, flat philtrum, short neck, long upper lip, saddle nose, and micrognathia or small jaw are some of the examples of distinctive facial characteristics.
- The patient may have a narrow chest and it can cause infections in the respiratory system.
- Radial deviation of the fingers with thumbs. Usually, they are broad and also in the hitchhiker’s position.
The symptoms and signs may vary from person to person and according to the patient’s condition. A proper full body examination can reveal all the symptoms of the Desbuquois Syndrome a patient’s body is going through.
Risk Factors of the Desbuquois Syndrome
The positive history of the patient’s family is a risk factor as Desbuquois Syndrome can be inherited to the coming generations.
Right now, there are no other risk factors identified, but still, there can be some other risk factors associated with the Desbuquois Syndrome.
If a person is genetically predisposed, it doesn’t mean that there will be an onset of the syndrome. The genetic predisposition only increases the chances of getting Desbuquois Syndrome as compared to the other people who doesn’t have any risk factor. Not having a risk factor doesn’t reflect that the person is not predisposed to get Desbuquois Syndrome. The patient should always discuss the risk factors with their health care providers.
Diagnosis of the Desbuquois Syndrome
Diagnosis of the syndrome depends upon the situation and condition of the patient. For proper diagnosis, the patient should always discuss the conditions with the health care provider regularly.
- Laboratory tests may be needed.
- Imaging Studies
- Evaluation of the medical history of the patient.
- Assessment of all the symptoms and signs the patient is showing up to advise a proper treatment plan to him/her.
- Some more tests might be suggested by the doctor based on the condition of the patients.
Complications of the Desbuquois Syndrome
There can be many types of complications a patient may face according to his/her condition, age, gender, body type, etc. Some of those complications are listed down below:
- Cleft Palate
- Sleep Apnea
- Club Foot
- Cryptorchidism (also known as undescended testicles)
- Severe Scoliosis
- Frequent or regular infections related to the respiratory system.
The patient may have to face complications before or even after the treatment of Desbuquois Syndrome. Sometimes, the treatments also cause some of the complications as everyone’s body responses differently to the treatment.
Treatment of the Desbuquois Syndrome
Treatment of Desbuquois Syndrome is based on the particular symptoms which the patient is suffering from or is present in an individual. Management of the syndrome and treatment include the regular orthopedic survey along with some important surgeries like hip and knee dislocations or scoliosis and follow-ups on ears and eyes. Some individuals reflect the syndrome from birth and they may need urgent attention so that in the long-term it doesn’t become worse.
Arthrodesis is a surgical procedure of fusion of joints. It may be advised to a patient who has faced several dislocations.
In order to control the progression of abnormalities related to the spine, physical therapy may be needed to manage severe scoliosis, which is a very common complication. Glaucoma may require surgery.
Some individual may require psychological support as they can feel different than other people because of some degree of shortness.
Preventions of the Desbuquois Syndrome
The risks can be understood better during pregnancy when the prenatal diagnosis and genetic testing of the expected parents and associated family members are done. Genetic counseling can help in planning a child and in the assessment or evaluation of the risks if there was any family history associated with the Desbuquois Syndrome.
Prognosis of the Desbuquois Syndrome
Due to respiratory failure, Type 1 Desbuquois Syndrome has reflected a high lethality rate of >33%. The individuals, who survive the syndrome, end up having delayed development, progressive and generalized joint laxity along with knee dislocations, and intellectual disabilities. The ambulation in Desbuquois Syndrome is usually limited because of orthopedic complications.
Patients suffering from mild conditions can get better prognosis as compared to patients who are facing very severe complications and symptoms.
Desbuquois Syndrome (DBQD) is a rare condition of osteochondrodysplasia. Osteochondrodysplasia is a disorder associated with the development of the bones and cartilage. Its features may vary according to its severity in the person suffering from it. Kyphoscoliosis, osteopenia, severe joint laxity are three of its characteristics. It can be inherited to future generations. It is one of the major risks of the syndrome if the family history is positive.
Desbuquois Syndrome Type 1 is caused by mutations in the gene named CANT1. Type 2 Desbuquois Syndrome is caused by mutations in the gene XYLT1 (16p12).
Some adults may face obesity, intellectual disability, intrauterine growth retardation, and generalized joint laxity causing joint dislocations as symptoms and signs of Desbuquois Syndrome. Cleft palate, sleep apnea, and club foot are three of the several complications caused by the syndrome or its treatments.
Diagnosis of the syndrome may include imaging studies, evaluation of the medical history of the patient, and assessment of all the symptoms and signs the patient is facing to advise a proper treatment plan to him/her. Other tests may be conducted according to the condition and symptoms of the patient.
It can be prevented with the help of prenatal and genetic counseling of the expected parents during pregnancy or before the birth of the child.
Till date, less than 50 cases have been reported and described in the medical history.
- LeMerrer, M., Young, I., Stanescu, V., & Maroteaux, P. Desbuquois syndrome. European Journal Of Pediatrics, (1991). 793-796. doi: 10.1007/bf02026714