Question 1: Explain the pathophysiologic defect of Cystic Fibrosis.
A mutation of a single gene, on chromosome 7, leads to the disease, cystic fibrosis. The gene is responsible for encoding the cystic fibrosis transmembrane conductance regulator (CFTR) protein. The normal CFTR is a regulator of chloride channels, which can lead to the regulation of chloride and sodium channels on the surface of the cell. The most common mutation leading to an abnormal CFTR is a mutation is delta F508. The disease can have different phenotypic manifestations depending on the extent of the mutation. The differences in chloride transduction leads to abnormal secretions in various organs, such as the lungs leading to difficulty in clearing the thickened airway secretions and build up of bacteria (Katkin, 2013).
Question 2: Describe the Autosomal Recessive inheritance pattern.
Because the trait is autosomal the disease itself can manifest in either females or males and can be passed down from either parent. Unlike autosomal dominant traits that manifest in heterozygotes, patients with diseases resulting from autosomal recessive inheritance patterns must be homozygotes. Each parent must have a defective copy of the gene, and each has a 50% likelihood of passing it down (Raby, 2013)
Question 3: Using a punnett square, display all possible combinations for transmission of this gene and expression in a child
Mother’s CF genes
C c
C: functioning CFTR; C: mutated CFTR. CC: unaffected non-carrier. Cc and cC: unaffected carrier. Cc: affected with CF
Question 4: Goblet cells and cilia are key components involved in the lung component of the disease process of CF. Explain the function and dysfunction of these cells and type of cell components in the CF patient
Cilia beat in a coordinated and rhythmic fashion to promote clearance of trapped material in the lungs, Goblet cells are mucus secreting cells; the main component is mucin which traps pathogens. In CF patients there is decreased clearance and increased viscosity of secretions leading to persistent respiratory infections, particularly pseudomonas (Harrison’s, 2008).
Question 5: Cite the common clinical symptoms presented in the case and describe other clinical manifestations typically seen in CF individuals.
PJ has many symptoms related to his cystic fibrosis. He suffers from repeated respiratory infections and has a cough representing the inability to clear the lungs. He also suffers from steatorrhea as a result of pancreatic insufficiency. Other clinical manifestations of CF that are seen in patients include, meconium ileus and distal ileal obstruction, rectal prolapse, biliary disease, infertility, musculoskeletal disorders, nephrolithiasis, and nephrocalcinosis (Katkin, 2013).
Question 6: What is the gold standard for diagnosing CF? Explain the reason why the test is used.
The gold standard for testing CF in patients is the sweat chloride test. The test is preformed with the application of pilocarpine on the skin to promote sweating. In CF patients the CFTR chloride channel is defective and therefore chloride is not reabsorbed in to the sweat ducts. More salt is thus reabsorbed into the duct while chloride remains in the sweat. Therefore we measure the chloride levels in these patients.
Question 7: Name the pancreatic enzymes involved in CF and their function.
Question 8: Explain the mechanism of action of the above medications as they relate to the pathophysiology of CF
Zosyn is a combined antibiotic composed of piperacillin and tazobactam. These are penicillins and are used to treat the chronic respiratory infections, particularly pseudomonas infection. Albuterol is a beta 2 agonist that promotes bronchodilation; this is also given for the airway reactivity that patients have. Fluticasone propionate is a glucocorticoid that works as an anti-inflammatory drug, due to the fact that neutrophilic infiltration is a dominant characteristic seen in CF patients. The final drug, Pancrelipase, is used to replace the pancreatic enzymes that are deficient as a result of the disease (Simon, 2013).
Question 9: Name 3 key nursing diagnoses for PJ, and list both medical and nursing interventions & rationale for each.
PJ is clearly has a fever and due to his cough and runny nose I would send out a sputum culture. I am suspecting him with coming in for a bacterial infection in his lungs, most likely pseudomonas; but also possibly Staph. Aureus or Haemophilus Influenzae. Another examination to be done would be to send in for a chest x-ray to check for pneumonia. If his lung problems get worse where he goes into respiratory failure I would hook him up onto a breathing mask. His abdomen and intestines need to be examined as he has lost weight with no vomiting. Asking about his fecal habits would be a start, because I would be worried about malabsorption.
Works Cited
Braunwald E., Fauci, S., Hauser S., Jameson J. Kasper D., Longo D., Loscalso J. (Eds.). (2008). Harrison’s Principles of Internal Medicine (17th edition) New York. McGraw Hill Medical.
Katkin, J. (2013) Cystic Fibrosis: Clinical Manifestations of pulmonary disease. UptoDate, Waltham, MA. Retrieved from: http://www.uptodate.com/contents/cystic-fibrosis-clinical-manifestations-of-pulmonary-disease?source=see_link
Katkin, J. (2013) Cystic Fibrosis: Clinical Manifestations and diagnosis. UptoDate, Waltham, MA. Retrieved from: http://www.uptodate.com/contents/cystic-fibrosis-clinical-manifestations-and-diagnosis?detectedLanguage=en&source=search_result&search=cystic+fibrosis&selectedTitle=1~150&provider=noProvider
Katkin, J. & Schultz, K. (2013) Cystic Fibrosis: Overview of gastrointestinal disease. . UptoDate, Waltham, MA. Retrieved from: http://www.uptodate.com/contents/cystic-fibrosis-overview-of-gastrointestinal-disease?detectedLanguage=en&source=search_result&search=cystic+fibrosis&selectedTitle=3~150&provider=noProvider
Simon, R. (2013) Cystic Fibrosis: Overview of the treatment of lung disease. UptoDate, Waltham, MA. Retrieved from: http://www.uptodate.com/contents/cystic-fibrosis-overview-of-the-treatment-of-lung-disease?detectedLanguage=en&source=search_result&search=cystic+fibrosis&selectedTitle=2~150&provider=noProvider
Raby, B. (2013) Overview of Mendelian Inheritance. UptoDate, Waltham, MA. Retrieved from: http://www.uptodate.com/contents/overview-of-mendelian-inheritance?detectedLanguage=en&source=search_result&search=autosomal+recessive&selectedTitle=1~150&provider=noProvider
