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Literature Review on Cystic Fibrosis Cystic Fibrosis is a complicated disease that affects mainly Caucasian patients. It is the most common autosomal recessive disease that affects this population. Approximately 30,000 cases of Cystic Fibrosis patients are affected in the United States with the incidence of 1 in 3, 300. Next in line are the Hispanics which has an incidence of 1 in 9, 000 cases, and less frequent in African Americans and Asian Americans which has an incidence of 1 in 15, 300 and 1 in 32, 500 cases, respectively. Over 10 million American are unknown carriers and there are 2, 500 cases of Cystic Fibrosis born annually The Cystic Fibrosis mutation was located in a gene found in the long arm of chromosome 7(7q31)that decodes the Cystic Fibrosis Transmembrane conductance Regulator(CF TR). This protein is the pump of chlorine depending on cyclic Adenosine-Mono Phosphate(cAMP), whose mutation leads to a failure on the three pairs of bases that decodes the phenylalanine in position 508, kno wn as delta F508 or AF5ltion of thal ion transport. There are more than 1,000 mutations identified and the most common is the del he CF TR mutation may be divided into five categories: First is the absence of CFTR production. Second is he production of CF TR, but failure in the intracellular processing and transport Third is the normal intracellular transport, but deregulation in the cellular membrane. Fourth is the normal expression of the cellular membrane, but change in the chlorine conductance and the last is the diminished synthesis. The first 3 categories are associated with a more severe disease Cystic Fibrosis can also be called mucoviscidosis, it is characterized by an abnomal mechanism of systemic ionic transport, which generates a diminished permeability to the chlorine, and causes recurrent pulmonary infections; chronic pulmonary obstructive disease; rhinosinusitis; nasosinusal polyposis; bad gastrointestinal absorption resulting from pancreatic dysfunction; spastic ileus of the newbom; retal prolapse and infertility for obstruction of the vas deferens In the respiratory epithelium, there is a failure in the chlorine secretion, which causes an excessive absorption of sodium, results in a higher water inf low to the cells and therefore increases the mucus viscosity The mucus becomes thicker than the normal by four-fold to six-fold. It does not affect the mucociliary beating directly, but it becomes inefficient in the clearance of such a viscous substance and generates stasis, that allows the ostia obstruction and increase of bacterial colonization, resulting to a recurring infection in the respiratory lining On the other hand, in the sweat glands epithelium, it leads to low absorption of chlorine and sodium of the glandular lumen, which results in sweating with a strong concentration of these The most frequent respiratory manifestations are chronic rhinosinusitis and nasosinusal polyposis It is 100% present among Cystic Fibrosis patients in the paranasal sinuses. The symptoms include nasal o struction, rhinorrhea, cough, headache, and facial pain. Although with repetition infection of the pulmonary disease is he 1st Cystic Fibrosis manifestation in 40% of the patients The Cystic Fibrosis diagnosis is made in the presence of one or more of the af oresaid clinical manifestations, associated with the presence of two gene mutations of the cystic Fibrosis or two positive results in the sweat test, (up to 30 mmol/L it's normal, from 30 to 60 mmol/L it's dubious and above 60 it,'s altered), or chang e in he nasal potential difference classical one includes pancreatic and sweating glands dysfunction(exocrine dysfunction), respiratory trac According to the level of the mutation found in the patients there are several phenotypes of the disease. Th disease and vas deferens malf ormation(males ). These patients normally have their diagnosis in the first six months of life and some of the diagnosis criteria, are as follows: the sweat test, may fail in certain patients which makes their identification dif ficult and may be taken for granted in the childhood There is also the presence of patients carriers of Cystic Fibrosis Transmembrane conductance gene mutation, who present with a higher proneness to the chronic sinusitis, recurrent pancreatitis or vas deferens obstruction without other features of the disease, which may confuse the diagnosis. However, it cannot fully determine how severe patients Cystic Fibrosis will be in the futureLiterature Review on Cystic Fibrosis Cystic Fibrosis is a complicated disease that affects mainly Caucasian patients. It is the most common autosomal recessive disease that affects this population. Approximately 30,000 cases of Cystic Fibrosis patients are affected in the United States with the incidence of 1 in 3,300. Next in line are the Hispanics which has an incidence of 1 in 9,000 cases, and less frequent in African Americans and Asian Americans which has an incidence of 1 in 15,300 and 1 in 32,500 cases, respectively. Over 10 million American are unknown carriers and there are 2,500 cases of Cystic Fibrosis born annually. The Cystic Fibrosis mutation was located in a gene found in the long arm of chromosome 7 (7q31) that decodes the Cystic Fibrosis Transmembrane conductance Regulator (CFTR). This protein is the pump of chlorine depending on cyclic Adenosine-MonoPhosphate (cAMP), whose mutation leads to a failure on the thal ion transport. There are more than 1,000 mutations identified, and the most common is the deletion of three pairs of bases that decodes the phenylalanine in position 508, kno wn as delta F508 or ΔF508. The CFTR mutation may be divided into five categories: First is the absence of CFTR production. Second is the production of CFTR, but failure in the intracellular processing and transport. Third is the normal intracellular transport, but deregulation in the cellular membrane. Fourth is the normal expression of the cellular membrane, but change in the chlorine conductance and the last is the diminished synthesis. The first 3 categories are associated with a more severe disease. Cystic Fibrosis can also be called mucoviscidosis, it is characterized by an abnormal mechanism of systemic ionic transport, which generates a diminished permeability to the chlorine, and causes recurrent pulmonary infections; chronic pulmonary obstructive disease; rhinosinusitis; nasosinusal polyposis; bad gastrointestinal absorption resulting from pancreatic dysfunction; spastic ileus of the newborn; retal prolapse and infertility for obstruction of the vas deferens. In the respiratory epithelium, there is a failure in the chlorine secretion, which causes an excessive absorption of sodium, results in a higher water inflow to the cells and therefore increases the mucus viscosity. The mucus becomes thicker than the normal by four-fold to six-fold. It does not affect the mucociliary beating directly, but it becomes inefficient in the clearance of such a viscous substance and generates stasis, that allows the ostia obstruction and increase of bacterial colonization, resulting to a recurring infection in the respiratory lining. On the other hand, in the sweat glands epithelium, it leads to low absorption of chlorine and sodium of the glandular lumen, which results in sweating with a strong concentration of these. The most frequent respiratory manifestations are chronic rhinosinusitis and nasosinusal polyposis. It is 100% present among Cystic Fibrosis patients in the paranasal sinuses. The symptoms include nasal o bstruction, rhinorrhea, cough, headache, and facial pain. Although with repetition infection of the pulmonary disease is the 1st Cystic Fibrosis manifestation in 40% of the patients. The Cystic Fibrosis diagnosis is made in the presence of one or more of the aforesaid clinical manifestations, associated with the presence of two gene mutations of the Cystic Fibrosis or two positive results in the sweat test, (up to 30 mmol/L it's normal, from 30 to 60 mmol/L it's dubious and above 60 it's altered), or chang e in the nasal potential difference. According to the level of the mutation found in the patients there are several phenotypes of the disease. The classical one includes pancreatic and sweating glands dysfunction (exocrine dysfunction), respiratory tract disease and vas deferens malformation (males). These patients normally have their diagnosis in the first six months of life and some of the diagnosis criteria, are as follows: the sweat test, may fail in certain patients, which makes their identification difficult and may be taken for granted in the childhood. There is also the presence of patient’s carriers of Cystic Fibrosis Transmembrane conductance gene mutation, who present with a higher proneness to the chronic sinusitis, recurrent pancreatitis or vas deferens obstruction without other features of the disease, which may confuse the diagnosis. However, it cannot fully determine how severe patients Cystic Fibrosis will be in the future
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