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progeria

progeria Progeria is a disease of children that produces rapid aging. The exact cause of progeria is unknown, although a hereditary component may be involved. Progeria results in rapid aging of children, beginning with growth failure during the first year of life. Progeria is a rare condition but has come into public awareness because of its startling symptoms and the appearance of several affected children in movies on national television.The children are small and thin with disproportionately large appearing heads, baldness, wizened narrow faces, and old-appearing skin. Children with progeria develop early atherosclerosis. The average lifespan is the early teens, although several have lived longer. The cause of death is usually related to the heart or a stroke as a result of the progressive atherosclerosis. There is presently no treatment for progeria. Support groups are available for the families of children with progeria. Precocious senility of striking degree is characteristic of this exceedingly rare disorder. Death from coronary artery disease is frequent and may occur before 10 years of age. Hastings Gilford gave the name progeria to this disorder in an article in which he also assigned the term ateleiosis to a pituitary growth hormone deficiency in 1904. He provided no photographs of progeria and indicated that only two well-marked instances have so far been recorded. Death from angina pectoris at age 18 years was noted. In 1886 Jonathan Hutchinson had previously written about the disorder . Ogihara in 1986 described a Japanese patient with progeria who survived to age 45, dying of myocardial infarction. Clinically, he seemed typical except for the unusually long survival. According to reviews of the literature, the age at death ranges from 7 to 27.5 years, with a median age of 13.4 years. Dyck in 1987 reported coronary artery bypass surgery and percutaneous transluminal angioplasty in a 14-year-old girl with this disorder. Recessive inheritance was suggested by the report from Egypt of affected sisters, children of first cousins. Paterson, in 1922 recorded the cases of two possibly affected brothers, photographs were not published and the diagnosis is not completely certain. The full report was simply the following: A boy, aged 8 years. Condition has been present since birth. The father and mother are first cousins. There are 4 children in the family, the girls are unaffected, both boys are affected. The senile condition of the skin and facies should be noted. The vessels show arteriosclerosis.(There is almost complete absence of subcutaneous fat.). Erecinski described photographically typical progeria in 2 brothers, and among the 9 offspring of 2 sisters, Rava in1967 found 6 affected. Khalifa in1989 described a consanguineous Libyan family in which 2 males and 1 female in 2 sibships related as cousins had seemingly typical Hutchinson-Gilford progeria. Repeated nonhealing fractures were the presenting manifestation in the proband. Maciel in1988 reported an inbred Brazilian family in which presumed Hutchinson-Gilford progeria had occurred in members of 2 sibships related as first cousins once removed. Although autosomal recessive inheritance was unmistakable, it was by no means certain that this involved true progeria. The two brothers reported as having progeria by Parkash in1990 probably had mandibuloacral dysplasia. In 1972 DeBusk maintained that of 19 cases reported to that date in which consanguinity was sought, in only 3 were the parents related. Conceivably progeria is a dominant and the rare instances of affected sibs are the result of germinal mosaicism. In 1990 Fatunde described a family in which 3 of 6 sibs had progeria. A seventh sib, who had died before the time of study, may have been affected. In 1972 DeBusk and Jones reported a paternal age effect, supporting autosomal dominant inheritance. In 20 cases in which parental age was known, the mean paternal and maternal ages were 35.6 and 28.8 years respectively, and the median ages 31 and 28 respectively. In 7 U.S. cases, the mean paternal age was 37.1. Brown favored autosomal dominant inheritance (most cases resulting from new mutation) because of the paternal age effect, the low frequency of parental consanguinity, and the report of progeric monozygotic twins with 14 normal sibs. Ayres and Mihan suggested that a fault in vitamin E metabolism may be at the root of progeria and recommended vitamin E therapy for its antioxidant effect. In cultured skin fibroblasts of patients with progeria,Goldstein and Moermandemonstrated an increased fraction of heat-labile enzymes and other altered proteins. Freshly obtained cells, namely, erythrocytes, showed similar heat-lability of G6PD and 6-phosphogluconate dehydrogenases in a girl with progeria. Both parents showed intermediate values, consistent with recessive inheritance. The primary source of the multiple protein defects is unknown. Normal HLA antigens were found by Brown. Brown described identical twins with progeria who developed heart failure at the age of 8 and died within 1 month of each other. Cytogenetic analysis showed aninverted insertion in the long arm of chromosome 1 in 70% of cells. Brown suggested that a gene for progeria may be located on chromosome 1. Evidence for possible bioinactive growth hormone was presented with a suggestion of treatment of progeria with growth hormone. Signs of infant progeria, the Hutchinson-Gilford syndrome, appear at about age one, after an evidently normal infancy. Affected individuals seldom exceed the size of a normal 5-year-old, although they have the physical appearance of 60- year-old adults by the time they are 10. Many of the superficial aspects of aging, such as baldness, thinning of the skin, prominence of blood vessels of the scalp, and vascular diseases, occur. Sex organs remain small and underdeveloped. A few individuals with progeria are mentally retarded, but most have normal intelligence and may even be precocious. By age 10, extensive arteriosclerosis and heart disease have developed, and most patients die before they reach 30; the median age of death is 13. A hereditary basis has been suspected, but there is no evidence to support the suspicion, and the cause remains a mystery. Werner's syndrome, sometimes called progeria of the adult, appears in young adulthood or, less commonly, in late adolescence. The aging changes are somewhat less pronounced, so that affected persons look about 30 years older than their chronological age. There is no dwarfism, as growth has been completed by the time the disease appears, but affected persons tend to be slightly shorter than average. Patients with Werner's syndrome are sexually mature, but secondary sex characteristics are poorly developed. Superficial signs of aging are premature balding or graying of hair, loss of teeth and hearing, cataracts, acute arthritic episodes, skin ulcers, and osteoporosis (loss of bony tissue). There is an increased tendency to develop heart disease, diabetes mellitus, and cancer, and the average lifespan is 47 years. This type of progeria is hereditary and is transmitted as a recessive trait, but its underlying cause is unknown. Bibliography:

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