Chondrodyplasia punctata of the rhizomelic type is one of the congenital malformations. The disorder is characterized by a striking short stature. The patient’s life expectancy is severely shortened in this disease.
What is chondrodyplasia punctata of the rhizomelic type?
Chondrodyplasia punctata syndromes are a group of different diseases. All subtypes are genetic diseases with characteristic features. Chondrodyplasia punctata of the rhizomelic type, or RCDP, was first documented in 1931. The most striking symptoms of the disease include short stature and mental retardation. The short stature is already evident in the newborn after birth. Prenatal diagnosis is possible if there is a known mutation within the family. Other symptoms of the disease include limitations in mobility and a conspicuous appearance. These include reduced hair growth and a flat face with chubby cheeks. According to current scientific knowledge, the disease cannot be cured. The course of the disease can be classified as very difficult. In most cases, patients die within the first decade of life. Due to the poor prognosis, additional care for close relatives is often required. Dealing with the disease is very difficult for all involved.
Causes
The cause of rhizomelic-type chondrodyplasia punctata is a genetic defect. This triggers a metabolic disorder of peroxisomes. Peroxisomes are involved in the construction of various and important cells in the organism. There are 3 types of the genetic defect. In most cases, changes occur in the PEX7 gene. The mutation here leads to a change in the PTS2 receptor. Type II is associated with a change in the GNPAT gene. This gene encodes the dihydroxyacetone phosphate acyltransferase. In type III, there is an alteration of the AGPS gene. This leads to a modification of the peroxisomal alkyl dihydroxyacetone phosphate synthase. The present gene defect is inherited autosomal recessively. The recessive mode of inheritance means that there is not necessarily an onset of the disease even though the gene defect is present. However, the defect can be passed on to offspring even without the onset of the disease. The probability of occurrence of rhizomelic-type chondrodyplasia punctata is reported to be 1 in 100,000.
Symptoms, complaints, and signs
Symptoms of chondrodyplasia punctata of the rhizomelic type include short stature. So-called rhizomelic short stature already exists at birth. This is manifested by shortened upper arms and thighs. The patient has sparse hair growth and a flat but chubby face. The lenses of both eyes are clouded. This results in a change in vision. The patient has a mental disability. This is associated with a greatly reduced intelligence. Most of the patients suffer from scoliosis which is hardly treatable. The mobility of the joints is severely limited. As a result, the patient is unable to move under his or her own power, or only to a very limited extent. Physical as well as psychosocial development is severely delayed. Skin lesions, changes in the vertebrae, and a cataract occur.
Diagnosis and course
If a parental gene mutation is present, prenatal diagnosis is possible. Prenatal diagnostics can be used to determine the genetic defect. In other cases, diagnosis occurs after birth to infancy. Imaging techniques such as X-rays reveal the shortening of the bone and vertebral structure. Performing a genetic test ultimately reveals the mutation of the affected gene and provides information about the type of genetic alteration present. Within the course of the disease, there is a worsening of the health condition. As the child grows, the present symptoms worsen. In addition, life expectancy is greatly reduced. Many sufferers die in the first decade of life. The most common cause is respiratory disorders that occur.
Complications
In most cases, there is a severely limited life expectancy due to chondrodyplasia punctata of the rhizomelic type. Affected individuals suffer from various malformations and deformities that limit their daily life.Likewise, there is reduced growth. The arms and thighs are shortened and the patient suffers from greatly reduced hair growth. Children in particular can become victims of bullying and teasing as a result of the symptoms. Vision decreases as the disease progresses, and complete blindness may result. Due to chondrodyplasia punctata of the rhizomelic type, mental development is also limited and retardation usually occurs. The motor development of the patient is also often limited, so that he is not dependent on the help of other people in everyday life. Not infrequently, the parents also suffer from chondrodyplasia punctata of the rhizomelic type due to psychological complaints or depression. A causal treatment is not possible. For this reason, only the symptoms are alleviated. In most cases, however, death occurs due to respiratory problems. The necessary therapies can thereby only relieve the symptoms and pain.
When should you go to the doctor?
Individuals with rhizomelic-type chondrodyplasia punctata must be closely monitored by a physician. Parents of affected children should therefore consult a chondrodyplasia specialist immediately after birth. The physician can clarify the symptoms and consult other specialists if necessary. Apart from this, chondrodyplasia punctata should be taken to the doctor if the complaints increase or new symptoms are added. If breathing difficulties occur as a result of the typical dysmorphia, the ambulance service must be called. The same applies if accidents occur as a result of the deformities. Later in life, the child should be presented to a therapist. Especially in case of noticeable growth retardation, the child must be supported by a specialist. For vision problems such as cataracts, it is best to contact the ophthalmologist or a specialist in eye diseases. In general, a person with rhizomelic-type chondrodyplasia punctata needs support throughout childhood and adolescence and often into adulthood. This makes it all the more important to start treatment early.
Treatment and therapy
There is no known treatment or therapy for chondrodyplasia punctata, as a cure is not possible according to current scientific knowledge. The symptoms that occur are treated individually and with the aim of alleviating them. Since the disease leads to a very low life expectancy, difficult and lengthy therapeutic measures are avoided when certain measures are taken. The body is in a weakened state and cannot adequately withstand many treatment methods. Since in most cases death occurs due to respiratory disorders, timely measures are taken to make this journey as comfortable as possible. The disease leads to the close relatives being exposed to a very heavy burden. Their entire lives are changed by the diagnosis. In addition, the shortened life expectancy of the child adds to the emotional challenge, which young parents find very difficult to cope with. For this reason, the parents are cared for in parallel with the patient. In order to cope well with the situation and the development of the disease, therapeutic measures are offered to all involved.
Outlook and prognosis
Chondrodyplasia punctata of the rhizomelic type has an unfavorable prognosis. The enzyme defect is caused by genetic factors and is not considered curable despite medical advances and numerous therapeutic options offered. The treatment plan is designed by the physician to alleviate the patient’s existing symptoms. The congenital malformations are individual to each newborn and are largely responsible for the further course of the disease. In addition to the prospect of little relief of symptoms, the disease also has a high mortality rate. Most patients die within the first decade of their lives due to the severe impairments. Respiratory disorders are mostly responsible for this. To make this journey more comfortable, appropriate precautions are taken or interventions are performed to prevent unnecessary agony. However, this can only be done if the patient’s state of health allows the necessary steps to be taken. Since in the case of genetic disease a prenatal test already gives the possibility of a diagnosis, the expectant mother can have an abortion induced if she wishes.After birth, due to the poor prognosis, medical treatment focuses on improving the existing quality of life and extending the average expected lifespan. Complex therapeutic measures or lengthy methods do not take place in this regard out of consideration for the low success and the newborn.
Prevention
In all syndromes of chondrodyplasia punctata, no preventive measures can be taken to avoid the disease. Chondrodyplasia punctata is due to a genetic defect. For legal reasons, interventions and changes in the genetics of humans are not allowed. People who have the genetic defect can refrain from fathering biological offspring. This excludes the possibility of passing on the defective gene. In addition, prenatal examinations of the unborn child are possible. These allow in utero diagnosis of chondrodyplasia punctata in the newborn.
Follow-up
In most cases of rhizomelic-type chondrodyplasia punctata, very few measures of follow-up care are available to the patient. In this case, the patient is primarily dependent on early diagnosis of the disease to prevent further complications. Since this is a congenital disease, a complete cure is not possible. As a rule, genetic counseling and testing can also be performed if children are desired, so that chondrodyplasia punctata of the rhizomelic type does not recur in the children. The earlier the disease is detected and treated, the better the further course of the disease usually is. The affected children are permanently dependent on the help and support of their parents. Loving care has a positive effect on the course of the disease. Since depression and psychological upsets can often occur, intensive and loving discussions with the affected person are necessary. Some therapeutic measures can also be carried out in the patient’s own home, making life easier for the patient. Chondrodyplasia punctata of the rhizomelic type has a very negative effect on the life expectancy of the child.
What you can do yourself
Chondrodyplasia punctata of the rhizomelic type is not considered causally treatable, and patients cannot take self-help measures to causally combat the disorder. Since it is a severe hereditary disease, genetic counseling is recommended for couples with a family history of rhizomelic-type chondrodyplasia punctata. The couples are then informed about the probability of the syndrome manifesting itself in their offspring and what health impairments can be expected in this case. In the case of parents-to-be whose family is affected by this hereditary disease, prenatal diagnostics can also be used to specifically search for this genetic defect. If the embryo is diseased, a medically induced abortion can be performed. Parents who decide to carry the pregnancy to term must be aware that their child will most likely not reach the age of ten. For the family members, this circumstance is usually more stressful than for the child, who is not aware of his or her condition due to the often severe mental disability. In any case, affected couples should seek psychological help at an early stage. In addition, all organizational measures necessary to integrate the care of a child with severe physical and mental disabilities into everyday family and work life should be taken while the child is still pregnant.
