A syndrome that is rarely observed the world over, the Costello syndrome is caused by mutations of the HRAS gene. It is responsible for uncontrolled cell growth in the human body, which leads to both cancerous as well as noncancerous tumors.
Basically a genetic disorder, the Costello syndrome leads to the delayed development of body systems in children. The occurrence of the disease is rare and very few develop this syndrome. Along with the delayed development, mental retardation, development of loose folds of skin, and unusual flexibility in the joints of the limbs, are characteristic to the syndrome. The related symptoms of this rare disease are, heart problems such as rapid heartbeat, overgrowth of heart tissues, and certain defects in its structural development. The phenomenon of overgrowth of heart tissues and rapid heartbeat are termed as hypertrophic cardiomyopathy and tachycardia.
The Costello syndrome is caused by the mutation of the HRAS gene. These mutations lead to the synthesis of a protein called H-ras. The body starts producing cells without any kind of external signal. The H-ras protein induces an uncontrolled growth of cells, which leads to the development of tumors that may be malignant or benign.
Signs and Symptoms
The children who suffer from Costello syndrome, are susceptible to the development of different types of tumors, that may be both cancerous as well as noncancerous. The noncancerous tumors are known as papillomas. The development of these tumors occur on the face, near the nose and mouth. The areas near the anus, too, show such a kind of tumors. The skin on the hands and feet becomes loose and dark.
Rhabdomyosarcoma, the connective tissue cancer, is seen among patients afflicted by this syndrome. A tumor of nerve cells, that is found in children as a result of the syndrome, is known as neuroblastoma. A cancer of the bladder, called transitional cell carcinoma, also develops in children due to this syndrome.
The reduction of growth hormones retards the growth among children, which affects their stature. There is a chance that the symptoms of patients suffering from this syndrome might be confused with that of the Noonan and/or Cardiofaciocutaneous syndrome.
There is no cure available for this syndrome. However, a cancer drug, Farnesyltransferase inhibitor is helpful in keeping a check on the action of the H-ras protein. Lovastatin is also a medicine known to affect the working of the H-ras protein. MEK inhibitor can also be used to treat the syndrome.
The treatment options available for this syndrome, today, focus on the various disorders and symptoms related to the syndrome. The patient is treated with different therapies that are physical as well as occupational. It helps the development of the body in a proper manner and helps reach full potential. Changes in the levels of blood pressure, tumor growth, and various orthopedic problems are monitored on a long-term basis.
The treatment involves many complications and risks. The number of children suffering from the syndrome is very less. This creates a problem for testing medicines developed for the treatment. However, attempts are being made to use animal models for the testing of the medicines.