Akademik

Cystic fibrosis

One of the most common grave genetic (inherited) diseases, CF affects the exocrine glands and is characterized by the production of abnormal secretions, leading to mucous build-up. This accumulation of mucus can impair the pancreas and, secondarily, the intestine. Mucous build-up in lungs tends progressively to impair respiration. Without treatment, CF results in death for 95% of affected children before age 5. However, with diligent medical care patients with CF are surviving even beyond middle age. Early diagnosis of CF is of great importance. Early and continuing treatment of CF is essential for long-term survival. However, as more people with CF survive childhood, new problems are emerging. For example, 68% of 75 adult women with CF reported leakage of urine within the past year. Coughing, sneezing, laughing and airway clearance provoked the leakage, which was worse when their chest disease was most severe. CF is inherited in an autosomal recessive manner and affects both boys and girls. One in 400 white couples is at risk for having children with CF and their risk with each pregnancy is 1 in 4, so (multiplying 1 in 400 times 1 in 4) the overall risk that their child will have CF is 1 in 1600. Note that once a couple has had a CF child, the risk that each of their subsequent children will have CF drops to 1 in 4 (25%). The treatment of CF includes physical therapy to loosen the mucus in the lungs, pancreatic enzymes, and medications to fight dangerous infections of the lungs. CF is caused by mutations in a gene called CFTR (for the cystic fibrosis conductance regulator), which is located on chromosome 7.

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cystic fibrosis n a hereditary disease prevalent esp. in Caucasian populations that appears usu. in early childhood, is inherited as an autosomal recessive monogenic trait, involves functional disorder of the exocrine glands, and is marked esp. by faulty digestion due to a deficiency of pancreatic enzymes, by difficulty in breathing due to mucus accumulation in airways, and by excessive loss of salt in the sweat called also fibrocystic disease of the pancreas, mucoviscidosis

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a hereditary disease affecting cells of the exocrine glands (including mucus-secreting glands, sweat glands, and others). The faulty gene responsible has been identified as lying on chromosome no. 7 and is recessive, i.e. both parents of the patient can be carrier without being affected by the disease. Affected individuals lack a protein, cystic fibrosis transmembrane regulator (CFTR), that enables the transport of chloride ions across cell membranes: this results in the production of thick mucus, which obstructs the intestinal glands (causing meconium ileus in newborn babies), pancreas (causing deficiency of pancreatic enzymes resulting in malabsorption and failure to thrive), and bronchi (causing bronchiectasis). Respiratory infections, which may be severe, are a common complication. Common agents include Haemophilus, Pseudomonas, Staphylococcus, and Burkholderia cepacia. The sweat contains excessive amounts of sodium and chloride, which is an aid to diagnosis.

Treatment consists of minimizing the effects of the disease by administration of pancreatic enzymes and physiotherapy for the lungs and by preventing and combating secondary infection. Sputum viscosity can be reduced by nebulized recombinant human DNAse. genetic counselling is essential, as each subsequent child of carrier parents has a one in four chance of being affected (see also mouthwash test). Some patients are benefiting from revolutionary new treatments, including transplantation of heart and lungs and treatment aimed at altering the genetic content of the faulty cells (see gene therapy).

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cystic fibrosis of pancreas an autosomal recessive disorder of infants, children, and young adults in which there is widespread dysfunction of the exocrine glands, with signs of chronic pulmonary disease (due to excess mucus production in the respiratory tract), pancreatic insufficiency, abnormally high levels of electrolytes in the sweat, and occasionally biliary cirrhosis. Pathologically, the pancreas shows obstruction of its ducts by amorphous eosinophilic concretions, causing the insufficiency and resultant steatorrhea and azotorrhea. The degree of involvement of organs and glandular systems may vary greatly, with consequent variations in the clinical picture. It is caused by mutations in the CFTR gene, which encodes the cystic fibrosis transmembrane regulator (q.v.), a cAMP-regulated chloride channel that regulates other ion channels.

Medical dictionary. 2011.