Holoprosencephaly is a malformation of the human brain that occurs with relatively high frequency. A large proportion of the affected embryos die in the womb. As a result, few patients with holoprosencephaly are born alive. Holoprosencephaly develops prenatally and mainly affects the face and the front of the brain.
What is holoprosencephaly?
According to abbreviationfinder, holoprosencephaly is relatively common, with a prevalence of between 1 and 4 cases per 1000 pregnancies . However, most affected children die in utero, so the disease actually affects between 5,000 and 20,000 live-born patients. Holoprosencephaly is more common in females than in males.
About half of those affected have chromosome aberrations. It is therefore necessary to carry out a chromosome analysis in the affected patients. Holoprosencephaly is particularly common in babies born to relatively young women.
Holoprosencephaly forms between the third and sixth week of life of the embryo. The reason is that the front area of the brain does not divide completely. The malformation results from impairments in the midlines of the skull. The forebrain, which consists of the diencephalon and endbrain, does not differentiate completely.
The exact processes and causes of the pathogenesis of holoprosencephaly are not known. In the majority of cases, holoprosencephaly is sporadic. However, there are probably also genetic factors, such as an undersupply of the substance cholesterol. This promotes the developmental disorder of holoprosencephaly.
There are also various favorable factors for the development of holoprosencephaly in the mother. For example, diabetes mellitus, toxoplasmosis and viral infections of the embryo have a beneficial effect on the development of the disease. Various external factors such as retinoic acid or hypocholesterolemia may also support the formation of holoprosencephaly.
In addition, there are numerous genetic diseases that are associated with holoprosencephaly with an above-average frequency. These include, for example, chromosomal anomalies such as trisomy 13, Joubert syndrome, trisomy 18 and the so-called 18p syndrome. Basically, an autosomal recessive or autosomal dominant mode of inheritance of holoprosencephaly is suspected.
Symptoms, Ailments & Signs
Holoprosencephaly is associated with various signs, but the spectrum of possible symptoms in different people is extremely wide. For example, some patients with holoprosencephaly suffer from a cleft lip and palate, narrow eyes, or a single central incisor.
Complaints such as cycloopia, arrhinencephaly and agenesis are also possible. A so-called corpus callosum agenesis sometimes also occurs. Alobar, lobar, or semilobar holoprosencephaly is found in the brain.
Diagnosis & disease progression
A diagnosis of holoprosencephaly is possible today using prenatal examination methods. Fine ultrasound techniques are primarily used for this purpose. In this way, holoprosencephaly can be diagnosed at relatively early stages in embryos in the womb.
Semilobar and alobar holoprosencephaly are usually discovered relatively quickly. On the other hand, the diagnosis of the lobar form of holoprosencephaly is often much more difficult. As soon as the existence of holoprosencephaly in the embryo is confirmed, the parents are given the option of terminating the pregnancy for medical reasons.
If they decide to keep the child, appropriate measures must be taken. These relate initially to the selection of the maternity clinic so that the newborn is optimally cared for. The diagnosis of holoprosencephaly is also carried out again or for the first time after birth. The doctor usually uses various imaging methods. These include an MRI examination, a sonography and a computed tomography.
In most cases, holoprosencephaly leads to the death of the child in the womb due to the various malformations in the brain. In many cases, the child’s parents experience mental health problems and depression that need to be treated by a psychologist. It can often take years for the mental health problems to improve.
If the child does not die before birth, various malformations and malformations will occur. Cycloopia or cleft palate occurs in most cases. This has a very negative impact on the patient’s everyday life. Often the sufferer has only a single incisor, which complicates the fatal overfeeding as well.
Complications can also occur during childbirth. In many cases, the parents also suffer from psychological problems after the birth due to the child’s deformities. Unfortunately, it is not possible to treat holoprosencephaly causally or symptomatically, so that the child dies in the first few months. In rare cases, however, the child can survive the first year of life and then has an increased chance of complete survival.
When should you go to the doctor?
Holoprosencephaly must always be examined and treated by a doctor. This disease does not heal itself and in many cases leads to the death of the affected person. The children often die in the womb, so that no further treatment is possible. A visit to the doctor can promote the diagnosis of holoprosencephaly, since the symptoms can be detected during an ultrasound scan. The mother has no other complaints.
However, regular examinations can detect holoprosencephaly at an early stage. In the event of a stillbirth or the death of the child shortly after birth, the parents concerned should consult a psychologist to avoid psychological upsets. If the child is born alive, the parents will need strong support from various doctors to keep the child alive. The child is usually dependent on a stay in the hospital.
Treatment & Therapy
Holoprosencephaly is currently not causally treatable. Patients therefore usually receive symptomatic treatment that is tailored to the individual case. In principle, most babies with holoprosencephaly die in the womb. The prognosis for live-born patients also tends to be negative.
In most cases, severe forms of holoprosencephaly lead to death within the first few months of life. The form of holoprosencephaly also affects the prognosis of the disease. The disease progresses less favorably in the alobar type than in the lobar or semi-lobar type.
In patients who survive their first year of life, there is often a more positive course of holoprosencephaly. In numerous cases, these individuals reach adulthood. However, these people also suffer from physical and cognitive disorders as well as neurological impairments.
These manifest themselves, for example, in epileptic seizures. Sometimes the sick children are not able to develop a spoken language. Sleep disturbances also occur comparatively frequently in persons affected by holoprosencephaly.
Outlook & Forecast
The prognosis of holoprosencephaly is extremely unfavorable. A majority of affected patients die in the abdomen during the development phase. The disease develops in the womb in the first few weeks of the developing embryo and cannot be treated. A diagnosis is made during the check-up visits within a pregnancy while it is still in the womb, but there is no possibility of initiating treatment or correcting the genetic defect.
When birth occurs, many newborns die immediately after delivery. Survivors cannot be adequately treated. They are born with sometimes severe brain malformations that cannot be changed. The treatment depends on the existing symptoms and is used to relieve the symptoms. The lifetime of a newborn with holoprosencephaly is significantly reduced. In addition, the patient will be dependent on outside help for the rest of his life. Various dysfunctions occur and severe mental retardation is present.
In addition to the poor prognosis for those affected, there are consequences or illnesses for the relatives. The mental stress can lead to a mental disorder in the parents. In addition to an anxiety disorder, trauma or depression, long-term impairments of well-being and loss of zest for life are possible due to the unfulfilled desire to have children or a stillbirth.
The causes of holoprosencephaly are not fully understood and in the majority of cases cannot be controlled. Because the disease is primarily caused by genetic and external factors. Only certain identified risk factors are partly within the sphere of influence of the expectant mother.
This includes, for example, diabetes mellitus. Studies also show that holoprosencephaly particularly affects very young pregnant women. Holoprosencephaly in the unborn child can be detected at an early stage through prenatal examinations.
Unfortunately, the majority of children affected by holoprosencephaly die in the womb or immediately after birth. In these cases, follow-up care is limited to psychological support for relatives. This should primarily be done by one’s own family and close friends and, if necessary, can be supplemented by psychotherapeutic therapy in order to reduce the risk of depression or other psychological problems.
If the child was born alive, it needs intensive medical care to keep it alive. In most cases, this happens in the first few months of life as part of a long hospital stay. The parents are gradually involved in the care and can later also advocate receiving intensive medical care as part of home care.
If the child survives the critical first year of life, the course is positive and there is a high probability that adulthood can be reached. Due to the many physical and cognitive disorders as well as the neurological impairments, however, they are dependent on outside help throughout their lives. The relatives should ensure that regular check-ups are observed and that any epileptic seizures and other symptoms and complaints that occur are treated accordingly by the doctor.
You can do that yourself
It is not possible to treat holoprosencephaly by self-help means. Many of the affected children die either in the womb or immediately after birth. In the event of an early death, the parents need psychological support. This should be done primarily by close friends or by your own family. But contact with a psychologist can also be of help to affected parents. With this help, psychological complaints or even depression can be avoided and reduced.
If the child survives the first years of life, in many cases it can also reach adulthood. However, the patients are dependent on help in their everyday life, as they cannot do many everyday things on their own. Ideally, this help comes from your own parents, relatives or friends. Contact with other people also always has a positive effect on the course of the disease on a psychological level. Cognitive disorders can be alleviated by various exercises.
In the event of an epileptic seizure, however, immediate medical treatment is necessary. Contact with other parents whose child suffers from holoprosencephaly can often have a positive effect on the disease and quality of life, as this leads to an exchange of information.