Cystic FibrosisCystic fibrosis is an autosomal recessive trait on chromosome 7.
Thisdisorder affects chloride transport resulting in abnormal mucus production.This lifelong illness usually gets more severe with age and can affect bothmales and females. Symptoms and severity differ from person to person. Cysticfibrosis is the most common fatal inherited disease among whites and the majorcause of chronic lung disease in children.
50% of people are expected to liveto be 30, but a majority die before age thirteen. 1:2000 whites have cysticfibrosis, 1:17000 blacks, 1:6000 live births, 1:2500 Americans, and 1:20 is acarrier.The genes are inherited in pairs, with one gene coming from each parentto make the pair.
Cystic fibrosis occurs when both genes have mutations. Aperson with cystic fibrosis receives one cystic fibrosis gene from each parent.The parents of a child, with cystic fibrosis, each carry one nonworking copy ofthe gene and one working copy of the gene. The parents are called cysticfibrosis carriers, and because they have one working gene they have no symptoms.Carrier parents have 1:4 chance to have a child who is a noncarrier of cysticfibrosis, a 1:2 chance to have a child who carries the gene, and a 1:4 chancewith each pregnancy to have an affected child.
If you have a son or daughterwith cystic fibrosis, then you have a 1:1 chance of being a carrier. If you havea brother or sister with CF, you have a 2:3 chance of being a carrier. If youhave a niece or nephew with CF, you have a 1:2 chance of being a carrier. Ifyou have an aunt or uncle with CF, you have a 1:3 chance of being a carrier anda 1:4 chance if you have a 1st cousin with CF.Cystic fibrosis affects the lungs in particular. The secretions arethick and sticky rather than thin and watery. This interferes with the removalof dust and germs.
It can lead to lung infections and even chronic lung damage.Air passages become clogged with mucus and there is often widespread obstructionof the bronchioles. Expiration is especially difficult. More and more airbecomes trapped in the lungs, which results in obstructive emphysema.Atelectasis can occur leaving small areas collapsed. Eventually the chestassumes a barrel shape.
The right ventricle, which supplies the lungs, maybecome strained and enlarged. Clubbing of the finger and toes may occur due tothe compensation response indicating the chronic lack of oxygen.Cystic fibrosis affects the pancreas. The mucus clogs the duct andblocks the transfer of enzymes from the pancreas to the intestines.
Theseenzymes are needed to break down food that is necessary for proper growth andweight gain. The mucus in the digestive tract blocks the absorption ofnecessary nutrients. This is why there is often no weight gain despite goodappetites. This can be associated with failure to thrive. The buttocks andthighs atrophy or waste away due to the fat disappearing from main deposit sites.People usually have light colored stools.
There is also decreased bloodcholesterol due to the poor absorption of fats from the intestine.Cystic fibrosis can also affect the reproductive systems. Men areusually sterile due to the mucus blockage or absence of the vas deferens. Womenusually have difficult conceiving, because the mucus interferes with the passageof sperm.Cystic fibrosis is usually diagnosed in childhood. Mild cases may notbe detected until adulthood. Common symptoms include chronic cough, wheezing,cyanosis, difficulty breathing, irritability, excessive mucus production, sinusinfections, nasal polyps, recurrent pneumonia, poor growth, frequent loose foul-smelling stools, enlarged fingertips, and skin that is salty to the taste. Thesweat test is usually used to detect high levels of salt.
More than 60m Eq/L ofchloride in sweat up to age 20 is diagnostic of CF when 1 or more criteria arepresent. Levels of 40-60 are highly suggestive. Direct genetic testing orreverse dot-blot can also be used. Amniocentesis is performed between weeks 15-22.
Chorionic villus sampling (CVS) can be used to take a piece of placentaltissue between weeks 9-12. Labs are also used in diagnosing CF. There isdecreased pancreatic enzymes trypsin, lipase, and amylase. Absence of trypsinalone is indicative of CF.One complication of CF is a rare condition known as meconium ileus. Theintestine of the newborn becomes obstructed with abnormally thick meconium dueto the absence of pancreatic enzymes.
The intestine can rupture resulting inshock. Signs and symptoms develop within hours after birth and include absenceof stools, vomiting, and abdominal distention. X-rays are used to confirm thisand surgery is used to correct the problem. The death rate is high includingpremature births and most who survive will manifest CF. Nurses in the nurserymust be on guard for early detection. Rectal prolapse occurs in infants andchildren due to poor muscle tone in the rectal area and excessive leanness. Itmay be related to difficulty passing the frequent bulky stools. Fecal impactionand intussusception or telescoping of the bowel are other bowel complications ininfants and toddlers.
The liver becomes hard, nodular, and enlarged withprogression. There is often edema in the extremities. There may be damage tothe eye as a result from swelling and inflammation of the optic nerve. Theretina may also hemorrhage. Improper lung function can cause heart strainresulting in death. Osteoporosis results from poor utilization of the fat-soluble vitamin D, which is necessary for proper calcium metabolism. The bonesbecome porous and brittle.
Deficiency of vitamin A occurs from the body’sinability to absorb fats from which vitamin A is obtained. Sexual developmentmay be delayed and women may experience secondary amenorrhea duringexacerbations.There is no cure to date. They have made progress towards a cure. Theyisolated the gene at U of M in 1989.
This was the first human genetic diseaseto be cloned. They thought it was linked to the trace mineral Boron. Copies ofthe normal gene were made in 1990. They realized that the protein product ofthe gene, transmembrane conductance regulator or CFTR, influences chloridetransport but were unsure how that led to CF. Gene therapy was experimented in1993 along with the first drug called Pulmozyme.
Ibuprofen was ruled effectivein decreasing lung problems in children in 1995. They ruled in 1996 that thebacteria killing agent doesn’t function in people with CF due to the excessivesalt outside the epithelial cells. This allows pseudomonas and staphlococcus tocause chronic bacterial infections.Treatment of CF includes taking Pancrease, an oral enteric coatedpancreatic enzyme preparation, with meals and snacks to help aid in digestion.
Fluids should be increased and liberal amounts of salt intake. Fluids areforced to prevent dehydration from frequent stools and excessive sweating.Salt tablets are often used in older children. Frequent high calorie mealsand snacks are used to help maintain weight.
Don’t pile food on a child’stray. Make it attractive and the size should correlate with the child’s size.Make mealtime a social time and encourage the child to eat. If he is in aprivate room, then stay with him or have someone in the room.
The nurse feeding an infant must be calm and unhurried. Caloriesshould be increased by 50% along with protein. Fat intake should decrease.
Supplement vitamins A,D, and E are used double the recommended daily dose.Skim milk is often added to formula in infancy. Vitamin K is often given.
Complex sugars should decrease and simple sugars should increase. Manydoctors allow the child to eat what he wants and just increases pancreaticenzymes to provide a “normal” atmosphere.Weights are taken daily.Respiratory relief comes from postural drainage, pursed-lip breathing,general exercise to stimulate cough, deep breathing and coughing exercises,bronchodilators, expectorants, antibiotic use, intermittent aerosol therapy,and the controversial mist tent therapy.
Injections should be avoideddue to the excessive leanness but if necessary the sites must be monitored andalternated. Pay special attention to the skin. Cleanse the diaper area aftereach bowel movement. Ointment is often used to protect skin from stools.
Expose the buttocks to air when a rash occurs. Pay special attention to thebony areas in order to prevent decubitus ulcers. Change position frequently dueto the lack of fat and muscle. This helps to prevent skin breakdown andpneumonia. Don’t leave the person staring at a blank wall. Air deodorant isadvisable to prevent lingering of offensive odors.
Light clothing isrecommended to prevent overheating. Loose clothing allows freedom of movement.Good oral hygiene is necessary especially due to dietary deficiencies. Makesure oral hygiene is also performed after postural drainage. Make sureimmunizations are up-to-date and the influenza vaccine is also recommended. CFpatients are usually in isolation to help prevent secondary infections. Allowfor rest.
This is very important as is prevention as a whole.CF is hard on children. They often feel different from other childrenand tire easily.It is hard for them to accept restricted activity. They getreally embarrassed about their stools.
Give the child straight forward answersregarding his illness to prevent further anxiety. Uninvolved diagrams can behelpful. If he understands, he is more apt to be cooperative. Visiting hoursshould be flexible for parents. You should be considerate and encouraging.Showing undue concern can, however, cause the child to exaggerate and bedemanding for attention.Parents may have knowledge deficit and may need a lot of teaching andexplanation. One of the misconception parents have is that their child’sintelligence is greatly decreased.
Intelligence is not affected. Parents oftenfeel guilty, since this is an inherited disease. The child spends the majorityof his time at home due to this lengthy illness. The child is also hospitalizedfor complications although stays are short to prevent exposure to otherinfections and illnesses. This puts a financial, physical, and emotional burdenon the family. When do the parents find time for each other, themselves, orother children? How do they distribute their time and energy equally andfairly? Parents need encouragement and reassurance. They also need explicitinstructions.
Parent groups can help along with the Nat’l CF ResearchFoundation and the 1-800-FIGHT-CF hotline. Parents usually need help from asocial worker and financial help for special equipment. Insist parents to gethelp from other family members or friends and encourage them to get away from itall periodically. Alarm clocks can remind them of medication times.