Friday, November 17, 2006

Cystic Fibrosis Treatments

Cystic fibrosis, which affects 30,000 American children and adults, is a multisystem disease caused by a defective gene. Presently only symptomatic management is possible, but there are very promising gene-therapy trials under way.

In the respiratory system the thin mucus lining becomes thick and sticky. In cystic fibrosis management, the primary treatment of the system is to thin or clear this mucus. Bronco dilators like albuterol are used to clear the clogged airways. Mucus thinning drugs delivered by aerosol, like pulmozyme, are helpful. The most effective way of clearing this mucus is by mechanically dislodging it. Clapping on the chest and back, with the head tilted on the edge of a table, is quite effective. There is an electrical clapper that does the job safely. There is an electrical inflatable vest that vibrates and dislodges the mucus. Infection is an ever-present risk with cystic fibrosis patients. Regular shots for pneumonia and influenza are very important. Bacterial infection is fought with newer antibiotics like TOBY, which delivers the medicine directly into airways with aerosols.

Because of the blocked ducts of the pancreas and liver, the enzymes and bile do not reach the intestine. Though the patient eats normally or even in excess, the fats and proteins are not digested. So the cystic fibrosis patient needs to have the enzymes supplemented with oral pancreatic enzymes. There is also the need to take vitamins, especially the fat-soluble ones. If lung function is completely damaged, the only alternative would be lung transplantation. This would involve many factors, like the availability of a donor and the patient’s present health, prior to undergoing major surgery.

The Cystic Fibrosis Foundation has 115 centers all over America, and provides guidelines and advice. They support many studies to find gene therapy to cure cystic fibrosis. The target is to add normal genes to the cells of the airways to prevent further damage. Biotech laboratories produce healthy genes, which need to be delivered to the appropriate cells. These vectors, or delivery systems, are the key areas of research to combat cystic fibrosis. One method that is actively pursued is to modify the common cold virus to carry the healthy genes into the correct cells. On another track, the DNA molecules are compacted to their minimum size and delivered directly to the relevant cells without the need for a carrier such as a virus. This technology is called PLAS min.