Xeroderma pigmentosum, or “moon child” disease, is extremely rare. Lunar child syndrome is a genetic defect that prevents sufferers from sun exposure. What are the causes of this serious pathology? How do you deal with it in everyday life? We take stock of this topic with Marie-Sylvie Doutre, dermatologist at Bordeaux University Hospital.
Xeroderma pigmentosum, what is the disease of the children of the moon? What are the causes?
The disease of the moon children, also called xeroderma pigmentosum (or XP), is a very rare disease in the general population, as Dr. Marie-Sylvie Doutre introduced: “In France we assume that it exists between 120 and 130 people affected by the syndrome of the children of the moon. Pathology is not new. Described around the 1870s, it is a disease manifested by hypersensitivity of the skin and eyes to the sun and UV rays.” Besides the sun, ultraviolet rays can actually be found in certain light sources such as halogen lights or even neon lights.
like dr Marie-Sylvie Doutre explains, the causes of Children of the Moon Syndrome are genetic: “For children to be carriers of the disease, that both parents are healthy carriers of this gene. This explains the very small number of people affected. In general, rates are higher in countries where consanguineous and intra-family marriages are common. The frequency is 1 birth in 1,000,000 in Europe or the United States and 1 birth in 100,000 in Japan and the Maghreb countries.
In order to explain how the disease works, it is necessary to understand that in each person, exposure to ultraviolet rays changes DNA. However, we have enzymes that repair the parts of DNA damaged by UV radiation. In general, this mechanism diminishes over time, hence the occurrence of skin cancer with age. In the Children of the Moon, the genetic abnormality prevents the enzymes from acting on DNA repair. Hence the hypersensitivity to sunlight.
Children of the Moon Syndrome will manifest itself through various symptoms that can appear at a young age, as Dr. Marie-Sylvie Doutre explains: “The symptoms appear in different stages in moon children. They are born with completely normal skin. In the first weeks and months of life, they show burns and severe sunburn in daylight. After the first year you can see pigment disorders on areas exposed to ultraviolet rays. These can be lighter or darker lesions on the skin (like freckles). Then skin tumors appear. Some can be benign or malignant. However, it is important to know that Children of the Moon syndrome has a variable intensity according to the profiles. Skin cancer can appear in the most severe forms in early childhood and in the less intense forms around adolescence.”
In addition to these skin symptoms, eye diseases can also occur in moon children: “The child will develop photophobia. That means the light will bother him a lot. more serious, corneal abnormalitiesConjunctivitis or eye tumors can also occur after exposure to UV rays”.
In the most serious cases neurological disorders can also occur in these children. These can be disturbances in the psychomotor development of the child or the development of deafness.
What is the life expectancy of moon children?
The life expectancy of lunar children has changed significantly in recent years, particularly with the media coverage of this little-known pathology. Effective care for young patients will be established from now on. It is assumed that the life expectancy of patients without protection against ultraviolet radiation does not exceed twenty years.
There is currently no real treatment for Children of the Moon Syndrome. The main support will concern the treatment of skin cancer developed by the patients. Surgical removal of tumors is usually done under local anesthesia. In the case of malignant tumors, radiation sessions and chemotherapy are performed. At the same time, the young patient is given vitamin D supplements to avoid deficiency symptoms, as the patient must avoid any exposure to the sun.
Although there are no treatments yet, the future remains hopeful. In fact, gene therapies are evolving, particularly in the United States, and are yielding significant results.
When treatments are minimal, the Syndrome of the Children of the Moon from photoprotection proves complex and difficult to manage, both for the children and for the parents, as Dr. Marie-Sylvie Doutre explains: “The photoprotection measures are numerous. It is necessary to install special window panesto prevent UV rays from penetrating. We also need to put it in the car, in the house, even in the classroom. A large amount of sunscreen should also be used. To prevent burns, this cream should be used all year round and applied very regularly. Children with the disease must also be equipped with a dosimeter. It’s a device that can detect the amount of ultraviolet rays in the room they’re in.”
Unfortunately, this way of life is extremely expensive. However, changes have taken place in recent years. Sunscreen cream is therefore reimbursed by social security for these children. On the other hand, sun protection devices such as windows and dosimeters are not yet reimbursed.
The Children of the Moon Club
If the disease of the Children of the Moon has been known for decades, it wasn’t until the turn of the 2000s that it became public. Founded by the Seris family, parents of twins with the condition, the Association of Children of the Moon has worked for years to raise awareness of this rare disease. In particular, the association helps the parents of sick children by providing dosimeters and protective masks. She has also worked in collaboration with NASA to develop effective protectants against ultraviolet rays.