Introduction
Progeria is a fatal genetic condition that occurs in young children and is characterized by premature aging (American Pregnancy Association, 2007). It is also referred to as Hutchinson-Gilford Progeria Syndrome (HGPS). It was named after the doctors who first diagnosed it (Jonathan Hutchinson and Hastings Gilford). It is rare and occurs in 1 per 4 million newborns.
Etiology of progeria
The definition of the origin of progeria has been slow and unclear. Investigations of the etiopathogenesis of progeria started with checking on the growth hormones-their responses were normal. “Abnormalities were found in skin collagen and elastin, where there is elevated collagen type IV and elastin production as well as early cell death” (Favr & Daire, 2001, p.56). Some studies showed reduced DNA repair in progeria cells. In 2003, it was found that about 90% of patients had a mutation in the LMNA gene that encodes for Lamin A protein, which holds the nucleus of a cell together. Defective Lamin A protein affects the morphology of the nucleus hence making it unstable (Favre & Daire, 2001).
Incidence of Progeria
The incidence of progeria refers to the “diagnosis rate of progeria or the number of news cases diagnosed over a given period” (Favr & Daire, 2001, p. 66). It occurs due to sporadic new mutation. It is rare and it is not easy for a family to have more than one case. It occurs as 1 case in 4-8 million newborns. According to Progeria Research Foundation (2001), only 54 cases have been reported worldwide, although it is suspected to be up to 150 more cases that remain undocumented.
Signs and symptoms of progeria
The signs and symptoms of progeria manifest themselves at the age of 9 to 24 months (Progeria Research Foundation, 2001). Progeria is a progressive disorder and is characterized by slow growth, low height and weight, hair loss (alopecia), eyelashes and eyebrows, a small face with a beaked nose, and prominent eye. The skin is wrinkled with prominent veins, hard and tight skin on trunk and extremities (scleroderma), thin lips, prominent eyes, high pitched voice, delayed and abnormal tooth formation, small lower jaw (micrognathia), stiff joints, osteolysis, insulin resistance, and irregular heartbeat. Other symptoms of progeria are skeletal abnormalities like osteoporosis, dystrophic clavicles, coxa valga, delayed closure of sutures, and fontanels. However, most studies showed that the patients’ intelligence is always normal. Death occurs at the age of 8-21 due to heart disease, atherosclerosis, and stroke.
Prognosis and therapy of progeria
Other aging syndromes mimic progeria. They are referred to as progeroid syndromes. They include wiedermann-Rautenstrauch syndrome, Hallerman-streiff syndrome, De Barsy syndrome, Mandibuloacral dysplasia and Werner syndrome (Falvre & Daire, 2001). Some of these syndromes, especially Werner can be mistaken for progeria. Therefore, proper diagnosis is recommended, and it may involve clinical and radiographic findings. The truncated mutation is one of the most important in the diagnosis of progeria. Radiographic abnormalities are present in the skull, thoracic cage, and phalanxes.
The fontanels and sutures remain open for longer. In the thorax, there is thinning and resorption of the distal clavicles. “The bones are long and slender with thin cortices; from the distal phalanxes of fingers and toes, which are progressively lost” (Abdenur et al., 1997, p. 126). Laboratory tests and exams reveal insulin resistance. Cardiac stress test reveals atherosclerosis of blood vessels while genetic test reveals changes in the gene that causes progeria.
There has been no specific therapy for progeria but symptomatic treatment is always advocated. This is meant to cure or manage the complications of the disease. For instance, coronary artery disease and cardiovascular disease can be monitored frequently. Falvre and Daire (2001) indicated that there have been reports of coronary artery bypass surgery or percutaneous transluminal angioplasty. Low doses of aspirin could be used to prevent heart attack and stroke. Abdenur et al (1997) proposed nutritional therapy to improve weight gain and growth. “Combination of nutritional therapy and growth hormone treatment showed improved growth and low basal metabolic rate” (Abdenur et al., 1997, p. 129). To avoid the growing or development of two rows of teeth due to delayed loss of primary teeth, extraction can be done.
Progeria Research Foundation (2001) new study identified Rapamycin to be a possible treatment for progeria. Rapamycin is an FDA drug that was found to extend the lives of non-progeria mouse models. According to research done in Massachusetts General Hospital, Boston, it was found that rapamycin was capable of reducing the amount of disease-causing protein progerin by 50% and extending the lifespan of progeria cells. Rapamycin was found to increase cells’ recycling system and clear the progerin more rapidly.
The foundation was also doing trials on three more other drugs which could be possible treatments of progeria. They include Lonafarnib, an FTI (Farnesyltransferase inhibitor) which was the first Progeria drug trial, pravastatin, and statin drug which is usually used for lowering cholesterol. Zoledronic acid, which is a bone drug used for improving osteoporosis was also included in the Triple Drug Trials. The foundation was expecting the trials to be a success if the drugs would improve weight gain and develop blood vessels activities (Agarwal et al., 2010).
References
Abdenur, J., Brown, W., Friedman, S., Smith, M., & Lifshitz, F. (1997). Response to nutritional and growth hormone treatment in progeria. Metabolism, 46, 851- 856.
Agarwal, U., Staraman, S., Mehta, S., & Panse, G. (2010). Hutchinson-Gilford progeria syndrome. Indian Journal Dermatol Venereol Leprol, 79(5), 591.
American Pregnancy Association (2007). Progera. Web.
Favre, L., & Daire, V. (2001). Progera. Web.
Progeria Research Foundation (2001). Groundbreaking Studies Identify new potential drug treatment, strengthen progeria-Aging link. Web.