Cystic Fibrosis Investigation

Cystic fibrosis is an autoimmune disease which is categorized as one of the chronic obstructive pulmonary diseases. This disease is caused by a mutation in a gene called cystic fibrosis transmembrane conductance regulator, which is located on chromosome 7. This gene is in charge of synthesizing the Cl^- channel protein. This protein is an anion-selective channel which allows for the passage of Cl^- ions. In a normal person, chlorine is involved in the alteration of swear, tear, digestive secretions, and mucous. A person with cystic fibrosis has defective Cl^- channels which results in abnormal epithelial transport of Cl^-. This imbalance of Cl^- affects the viscosity of exocrine gland secretions. The exocrine glands of a person with cystic fibrosis produce abnormally viscid mucous. This mucous obstructs the bronchiole airways which causes symptoms such as coughing and wheezing. The thickened mucous also traps many bacteria, making it easy for the bacteria to grow and cause infections. Therefore, another common symptom of cystic fibrosis is repeated respiratory infections. In addition to the Cl^- imbalance, the defect in the Cl^- channel protein also causes an increased Na⁺ and water reabsorption. This further thickens the mucous and make it difficult for the mucous to clear out of the bronchiole airway. Overtime continual obstruction of the bronchioles can cause lesions in the epithelial lining as well as degenerative changes in the alveoli. Some manifestations of this disease include affect the digestive system with symptoms such as diarrhea or bulky, foul smelling, greasy stools. This is because the viscous mucous can also block ducts in the pancreas, which prevent enzymes from reaching the intestines. Without these enzymes the intestine cannot absorb fats and proteins adequately. The Cl^- imbalance may also result in very salty sweat and a salty taste when kissing a baby’s face.

“What Are the Signs and Symptoms of Cystic Fibrosis?” National Heart Lung and Blood Institute, U.S. Department of Health and Human Services, 26 Dec. 2013, www.nhlbi.nih.gov/health/health-topics/topics/cf/signs.

“Cystic Fibrosis Foundation.” CF Foundation, www.cff.org/What-is-CF/About-Cystic-Fibrosis/