About xerodermic idiocy

What is xerodermic idiocy?

De Sanctis-Cacchione syndrome is an extremely rare disorder characterized by the skin and eye symptoms of xeroderma pigmentosum (XP) occurring in association with neurological abnormalities, mental retardation, unusually short stature (dwarfism), and underdevelopment of the testes or ovaries (hypogonadism). Xeroderma pigmentosum is a group of rare inherited skin disorders characterized by a heightened reaction to ultraviolet light (photosensitivity), skin discolorations, and the possible development of several types of eye disorders and skin cancers. The most common neurological abnormalities associated with De Sanctis- Cacchione syndrome are low intelligence, an abnormally small head (microcephaly), the loss of ability to coordinate voluntary movement (ataxia), and/or absent (areflexia) or weakened (hyporeflexia) reflexes. De Sanctis-Cacchione syndrome is inherited as an autosomal recessive trait.

What are the symptoms for xerodermic idiocy?

In De Sanctis-Cacchione syndrome, the earliest symptoms are the skin abnormalities associated with xeroderma pigmentosum (XP) including excessive freckling and blistering occurring after exposure to ultraviolet light (photosensitivity). In some cases, pain and blistering may occur immediately after contact with sunlight. Acute sunburn and persistent redness or inflammation of the skin (erythema) are also early symptoms of De Sanctis-Cacchione syndrome. In most cases of XP, these symptoms may be apparent immediately after birth or by the age of three years. However, in some rare cases, symptoms may not be apparent until later in childhood. In most cases of De Sanctis-Cacchione syndrome, onset is often during infancy.

Additional skin symptoms often associated with De Sanctis-Cacchione syndrome include unusually dark (hyperpigmentation) or light (hypopigmentation) areas of skin. In some cases, complete loss of skin color (depigmentation) and/or excessive scarring may occur. Wart-like lesions (actinic keratoses) may develop, as well as small red Skin lesions (telangiectasias) that are caused by abnormal widening of tiny blood vessels near the surface of the skin. The skin may also become weak and easily damaged. Degenerative (atrophic) changes may occur and the skin may appear dry and smooth.

Most children with De Sanctis-Cacchione syndrome usually have one or more neurological abnormalities; the most frequent is low intelligence. Other abnormalities may include an unusually Small head (microcephaly); hearing impairment (sensorineural deafness); absent (areflexia) or weakened (hyporeflexia) reflexes; and/or increased rigidity in some muscles causing stiffness and limitation of movement (spasticity). Affected individuals may also exhibit loss of the ability to coordinate voluntary movements (ataxia) and/or abnormal Involuntary movements of the body such as uncontrolled jerky movements combined with slow, writhing movements (choreoathetosis).

De Sanctis-Cacchione syndrome is occasionally associated with slow progressive degeneration of part of the brain known as the cerebellum (cerebellar atropy) and/or any of a group of progressive disorders involving degeneration of other parts of the brain (i.e., cortex, basis pontis, and inferior olivary nuclei). This clinical picture is similar to that seen in the hereditary olivopontocerebellar atrophies. Symptoms may include impaired muscle coordination (ataxia), tremors, involuntary movements, and speech disturbances (dysarthria). 

Individuals with De Sanctis-Cacchione syndrome will also exhibit unusually slow development, profound Growth delays resulting in Short stature (dwarfism), mental retardation, and/or inadequate function of the testes or ovaries (hypogonadism).

Benign skin tumors may be associated with De Sanctis-Cacchione syndrome, with onset possible before the age of five. These may include tumors that are pre-malignant or benign (non-cancerous), such as tumors made up of blood vessels (angiomas) and/or rapidly growing tumors often occurring on sun-exposed areas of the skin.

Individuals with De Sanctis-Cacchione syndrome may experience an early onset of skin cancer. For example, skin cancers such as malignant melanoma, basal cell carcinoma, and squamous cell carcinoma often occur in individuals with this disorder; the most commonly affected areas are the head, neck, and face.

In De Sanctis-Cacchione syndrome, some of the eye symptoms associated with XP may be present. These may include an extreme intolerance to light (photophobia); inflammation of the corneas of the eyes (keratitis); inflammation of the membrane that covers the white portion of the eyes (conjunctivitis); outward facing of the eyelids (ectropion); and/or inward facing of the eyelids (entropion). The severity of symptoms related to the skin and eyes may depend on the amount of exposure to ultraviolet light.

What are the causes for xerodermic idiocy?

De Sanctis-Cacchione syndrome is inherited as an autosomal recessive trait. Human traits, including the classic genetic diseases, are the product of the interaction of two genes, one received from the father and one from the mother.

Recessive genetic disorders occur when an individual inherits the same abnormal gene for the same trait from each parent. If an individual receives one normal gene and one gene for the disease, the person will be a carrier for the disease, but usually will not show symptoms. The risk for two carrier parents to both pass the defective gene and, therefore, have an affected child is 25% with each pregnancy. The risk to have a child who is a carrier like the parents is 50% with each pregnancy. The chance for a child to receive normal genes from both parents and be genetically normal for that particular trait is 25%.

In approximately 30 percent of the documented cases, individuals affected by De Sanctis-Cacchione syndrome have had parents who were related by blood (consanguineous). All individuals carry 4-5 abnormal genes. Parents who are close relatives (consanguineous) have a higher chance than unrelated parents to both carry the same abnormal gene, which increases the risk to have children with a recessive genetic disorder.

Investigators have determined that some cases of De Sanctis-Cacchione syndrome may be caused by disruption or changes (mutations) of a certain gene located on the long arm (q) of chromosome 10 (10q11). Chromosomes, which are present in the nucleus of human cells, carry the genetic information for each individual. Pairs of human chromosomes are numbered from 1 through 22, and an additional 23rd pair of sex chromosomes which include one X and one Y chromosome in males and two X chromosomes in females. Each chromosome has a short arm designated “p” and a long arm designated “q”. Chromosomes are further sub-divided into many bands that are numbered. For example, “chromosome 10q11” refers to band 11 on the long arm of chromosome 10. The numbered bands specify the location of the thousands of genes that are present on each chromosome.

What are the treatments for xerodermic idiocy?

In individuals with De Sanctis-Cacchione syndrome total protection of the skin from sunlight (e.g., topical sunscreens, sunglasses, double layers of clothing) is necessary to prevent the development of skin lesions and other complications (e.g., skin cancers and some neurological symptoms). Affected individuals with De Sanctis-Cacchione Syndrome must limit outdoor activities during daylight hours to avoid exposure to ultraviolet light. Avoidance of chemical carcinogens, such as those in cigarette smoke, is also recommended.

For individuals who have skin cancer, early detection and surgical removal of the lesions is essential. Regular examinations of the skin and eyes by specialists is recommended. Genetic counseling will be of benefit for affected individuals and their families. Other treatment is symptomatic and supportive.

What are the risk factors for xerodermic idiocy?

The xerodermic idiocy syndrome consists of xeroderma pigmentosum and mental and physical retardation. The syndrome was inherited as an autosomal recessive trait

1. Monozygosity was established by clinical features, blood types, and dermatoglyphics. Biochemical studies were normal, but an electroencephalogram showed diffuse disturbance of cerebral function in both twins. Their bone age was retarded by about two years.
2. A skin biopsy showed hyperkeratosis, atrophy of the rete ridges and hyperpigmentation of the basal cells, but no malignant change.
3. The malignant change was to be due to high exposure to sunlight.
4. Neither consanguinity nor clinical evidence of the disease was present in the parents. A mutant gene of large effect is thought to be the cause of the syndrome. The underlying pathogenesis of the skin lesion is briefly discussed.
5. In inherited an autosomal recessive condition, both parents must be heterozygous carriers of the mutant gene.
6. Although there are reports suggesting that freckling is seen in heterozygotes the parents did not show any clinical evidence of the disease.

Xeroderma pigmentosum,Mental and physical retardation
Hyperkeratosis,Atrophy of the rete ridges and hyperpigmentation of the basal cells, but no malignant change
Symptomatic treatment and therapies

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