What Is Cystic Fibrosis?

Your child is under weight, has greasy, smelly diarrhea, a chronic cough and seems to always be getting pneumonia. He wheezes when he breathes and has impaired exercise ability. He seems to never being growing to the average size of his peers and his skin is very salty (5). The doctor’s first instinct should be to test your child for a disease called cystic fibrosis. Cystic fibrosis is a disease, which causes the mucus in your body to be thicker in some areas. The most affected areas are the lungs and digestive system. As a result, the person may get chest infections and have difficulty digesting food. When cystic fibrosis is a consideration for a person’s disease the physician will do what is called a sweat test. This is a simple and cheap way to determine if your child has the disease. Because people who have cystic fibrosis (CF) have saltier sweat than others, the sweat test detects the amount of salt in the sweat of the individual (4). This is the best way to diagnose a person with the disease (5).

CF is a genetic disease, meaning that a person does not “catch it”, it is inherited in the genes passed down to the person. Cystic fibrosis lasts with the patient for their whole life. This makes it a chronic disease, not communicable (9). All symptoms of CF are caused by a mutation to the single chromosome 7. This particular gene is responsible for the building of the protein called the cystic fibrosis trans membrane conductance regulator (CFTR). Normally, the gene regulates the passage of chloride ions in and out of the cell, but when mutated as in the case of CF patients the chloride ions cannot move throughout the cell membrane because the CFTR does not open. In about three- quarter of CF cases the CFTR is not just broken, but is completely missing from the cell. The missing CFTR has many effects on the human body. One is saltier sweat because as the sweat rises to the skin, cells reabsorb sodium and chloride molecules. The loss of the CFTR does not allow the body to reabsorb the sodium ions making a CF patient’s sweat five times saltier than that of a normal person. This can lead to irregular heart rhythms. The loss of chloride ions affects the pancreas also. The loss of the CFTR ultimately makes it impossible for digestive enzymes to be sent to the intestines. A normal CFTR allows water to follow chloride through the duct and out of the cells, but when the CFTR is missing then the chloride and water remain inside the cells. The enzymes are unable to be carried away, causing the enzymes to digest the pancreas itself. This leads to inflammation and thick mucus plugging the duct. It is not exactly known why, however the organ that suffers the most damage from the lack of CFTR is the lung. For some reason, the mucus becomes very thick in the lungs and leads to a lot of bacterial growth. The mucus is the perfect living environment for bacterial growth causing all kinds of infections. Being hard to rid, the mucus builds up in the bronchial tubes and reduces the surface available for oxygen exchange. When the body tries to kill the infection, the enzymes in turn causes more lung damage. More lung cells are killed, and chronic infections seriously damage the lung (whole paragraph from 6).

There is no way to prevent someone from contracting CF. The only thing that could be done is for everyone to be know whether or not they are a carrier, and whether or not their partner is a carrier. In order for a child to be born with CF, both parents must be carriers for the disease. A person may be a carrier and not even know it, carriers of the disease have absolutely no characteristics of the disease, but they simply are able to pass on the gene to their offspring. When one carrier has a child with another there is a twenty-five percent chance that the child will have CF. There a fifty percent chance that the child will be a carrier for the disease and there is a twenty-five percent chance that the child will not be a carrier or have the disease (7).

There is no cure for cystic fibrosis, but treating the effects of the disease is the only thing that can be done. Doctors generally will put the patient on anti-biotics to control infections. Chest physical therapy can be done