Peters-Plus syndrome is a very rare eye disorder in which the development of the anterior segment of the eye is disturbed. The disorder is due to a gene mutation. Treatment focuses on alleviating the resulting symptoms. Corneal transplantation is one treatment option.
What is Peters plus syndrome?
Peters-Plus syndrome, or Krause-Kivlin syndrome, is an eye disorder that is hereditary. Medical literature describes only about 20 cases; thus, the condition is not only very rare, but among the rarest diseases of all. As a leading symptom, doctors refer to Peters’ anomaly, which is characterized by a malformation of the anterior chamber of the eye. It is only since 1984 that medicine has described Peters-Plus syndrome as an independent syndrome that can be distinguished from similar clinical pictures.
Causes
The cause of Peters-Plus syndrome is genetic. The developmental disorder of the anterior segment of the eye is due to a mutation in the gene B3GALTL. Each gene encodes a specific sequence of amino acids that make up proteins. This gives rise to various structures and signaling substances. The B3GALTL gene contains information about the synthesis of an enzyme that acts as a biocatalyst to promote biochemical processes in the body. In this case, it is beta-1,3-galactosyltransferase. Among other things, this enzyme participates in the synthesis of sugar chains. According to a new study from 2015, the mutation could promote a disruption of quality control in the endoplasmic reticulum. The endoplasmic reticulum is a structure within human cells that is responsible for transporting substances, among other things. Inheritance of Peters-Plus syndrome is autosomal recessive. This means that the disease only manifests itself if both parents pass on a mutated allele to the child. As soon as a healthy allele is present in the genome, the disease does not manifest itself. The affected allele is located on an autosome, i.e. not on a sex chromosome.
Symptoms, complaints, and signs
The most important sign of Peters-Plus syndrome is the so-called Peters anomaly. This is an abnormality of the eyes characterized by underdevelopment of the anterior chambers of the eye. The anterior chamber is located behind the cornea. Peters’ anomaly leads to a malformation of the lens, possibly resulting in a cataract in which the lens of the eye is clouded. Affected individuals experience the cataract as a cloudy haze in their visual acuity, which may be associated with higher sensitivity to glare. In addition, the iris may become stuck in the chamber angle. In addition, Peters’ anomaly can cause nystagmus. These are rhythmic eye movements that are beyond the control of the affected person. The syndrome leads to glaucoma in half of those affected, which puts the optic nerve at risk. Furthermore, affected individuals often suffer from short stature, brachydactyly (shortened fingers and toes), cleft palate, and hypermobility. The latter is characterized by unusual mobility of ligaments, tendons and joints. Individuals with Peters-Plus syndrome often have a small head, round face, and conspicuously large cerebral ventricles. The philtrum and fontanel are more pronounced than average. Heart defects, kidney disorders, respiratory disorders, clinodactyly, and polyhydramnios may also be signs of Peters-Plus syndrome. As a result of the various symptoms, motor and mental development may be delayed.
Diagnosis and course of the disease
Initial clues to Peter Plus syndrome are provided by the characteristic malformation of the eyes, the resulting symptoms, and the general clinical presentation. Ophthalmologists can differentiate the symptomatology from other diseases by performing detailed examinations. Differentially, physicians must primarily consider Rieger syndrome, Weill-Marchesani syndrome, and Cornelia de Lange syndrome. A genetic test can detect the mutated gene B3GALTL and thus bring absolute certainty about the presence of Peter Plus syndrome.
Complications
In the worst case, Peters-Plus syndrome results in complete blindness of the affected person. However, this usually occurs if no treatment for the disease is given.Particularly in young people, sudden blindness or severe vision loss can lead to severe psychological discomfort or even depression. The quality of life of the affected person is also significantly reduced by the disease, so that in many cases patients are dependent on the help of other people. In addition to eye complaints, those affected also suffer in many cases from short stature or heart defects. Disorders of the kidneys or diseases of the respiratory tract also occur relatively frequently in Peters-Plus syndrome and can thus lead to a reduced life expectancy. The children suffer from significantly delayed development and thus from various mental and motor disorders, so that bullying or teasing may also occur. Peters-Plus syndrome can be treated by surgical intervention. Complications do not occur and the symptoms can be alleviated. This prevents complete blindness of the affected person. The other complaints are also treated according to their occurrence. No particular complications occur in this process.
When should one go to the doctor?
Peters-Plus syndrome is a very rare hereditary disease. A specific diagnosis is only possible if there are pronounced symptoms that persist over a long period of time. If the child shows signs of underdevelopment in the area of the eyes, the responsible physician should be informed. Corneal opacities or adhesions of the iris indicate a disease of the eyes, which must be medically examined. Also short stature as well as the typical round face are symptoms in need of clarification. The physician can diagnose Peters-Plus syndrome by means of an ultrasound examination of the cornea and suggest symptomatic treatment. If there are already cases of the rare disorder in the family, early diagnosis is possible. Parents of affected children should keep close contact with the pediatrician and inform the doctor in case of complications. The condition is treated by the ophthalmologist and an optometrist, who can prescribe appropriate visual aids. Routine examinations can be performed by the pediatrician. In individual cases, corneal transplantation is possible, which is always performed by a team of surgeons as an inpatient.
Treatment and therapy
Because Peters-Plus syndrome is due to a gene mutation, its cause is not treatable today. Instead, therapy focuses on alleviating the various symptoms that occur as a result of the condition. Corneal transplantation may improve symptoms. Also known as keratoplasty, it is the most common type of transplant and can be used for a variety of different conditions. For the transplantation, the surgeon completely removes the damaged corneal layers and replaces them with corneal flaps that come from a donor. Living donation is not possible: a surgeon removes the corneal flaps from a deceased person who voluntarily decided to donate an organ during his or her lifetime. Donors can provide all or only certain organs as a donation. High pressure inside the eye significantly increases the risk of blindness. Intraocular pressure increases in Peters-Plus syndrome because the aqueous humor cannot drain properly as a result of the malformation of the anterior chamber. As a consequence, not only the volume in the ciliary body increases, but also the pressure on the eye wall; glaucoma is the result. For example, it can damage the optic nerve, which transmits electrical signals from the photoreceptors.
Outlook and prognosis
Peters-Plus syndrome, which is extremely rare, occurs in infancy. To date, 20 cases have been reported worldwide. This unilateral or bilateral eye disease is also known as Krause-Kivlin syndrome. The disease does not have a good prognosis despite surgical intervention. It may be assumed that this defect is so severe in its worst manifestation that most fetuses that are affected never fully develop. Peters plus syndrome results in Peter’s anomaly. This is associated with a variety of symptoms. The severity of the malformations can vary from individual to individual. Therefore, the outlook also varies. However, the affected children are not only affected by serious problems and malformations of the eyes.They may also be affected by a variety of other malformations that affect the entire body. So far, there is no cure for Peters-Plus syndrome, which is caused genetically, or by a mutation. Because of the serious eye problems, those affected are usually severely visually impaired. They must be cared for in appropriate institutions. The other defects, malformations and disorders are also so severe that the children can never enjoy a normal life. In some cases, corneal transplants or other surgical interventions in the eye area can be considered. Otherwise, only symptomatic treatments are available to relieve symptoms.
Prevention
Specific prevention of Peters-Plus syndrome is not possible. Because the disease is based on a genetic mutation, only very general prevention is conceivable. The syndrome is inherited recessively and therefore manifests only if both parents carry and inherit the mutated gene. If the parents are related, the likelihood of two altered alleles coming together in the child’s genome increases significantly. Even if both parents independently carry the mutated B3GALTL gene, the child’s risk of developing Peters-Plus syndrome increases. With the help of prenatal diagnostics, doctors can already determine in the fetus whether it carries two mutant alleles.
Follow-up
In most cases of Peters-Plus syndrome, the affected person has very few, if any, special measures and options for aftercare, since the disease cannot be fully treated. Since it is a congenital disease, the affected person should in any case first undergo genetic testing and counseling if he or she wishes to have children, in order to prevent the recurrence of the syndrome. As a rule, early diagnosis generally has a very positive effect on the further course of the disease and can also prevent the occurrence of further complications. In most cases, patients with this disease require surgical intervention, which can significantly alleviate the symptoms. After such an operation, the affected person should protect the eye particularly well and generally take it easy. The eye pressure should also be checked regularly, since in the worst case complete blindness can occur, which is irreversible. As a rule, no further follow-up care is necessary after treatment. The patient’s life expectancy is also not negatively affected or otherwise reduced by this disease.
Here’s what you can do yourself
Peters-Plus syndrome is a severe disease that has no causal treatment to date. The most important self-help measure is to protect the eyes. Sunlight and contact with pollutants should be avoided. In addition, sufferers should not strain their eyes with shampoos, eye drops, or the like. Since the disease progresses progressively, the visual aid must be regularly adjusted to the current visual ability. If visual complaints occur, a visit to the doctor is recommended. Other self-help measures are limited to a healthy lifestyle with a balanced diet and avoiding stress. This can positively influence the veraluf of the ophthalmological symptoms associated with Peters-Plus syndrome. Affected persons should act prudently in everyday life, as there is an increased risk of accidents due to impaired vision. Particularly when climbing stairs and during sports, attention must be paid to possible sources of danger. If there are more falls and other problems, an adjustment of the spectacle strength is necessary. Despite all measures, the Peters-Plus-Syndrome can have a negative influence on the well-being. For this reason, talk therapy with a psychologist is always an option, which can accompany medical treatment.
