Cystic Fibrosis Flashcards
CF is ___ and affects what?
Purely genetic
lungs pancreas, other organs
____ Canadians are CF carriers
1/25
How many canadians hav CF?
1/3600
How many mutations of CFTR gene?
Over 2,000
(T/F) CF is more prominent on females, who tend to be underweight
T
What are the chances that two carrier have a child with CF? Without CF? Carrier of CF gene?
With: 25%
Without: 25%
Carrier: 50%
What are chances that one carrier and one non-carrier have a child with CF? Carrier of CF?
0% with CF but all carriers
Cf is a ___ gene
recessive
Class I?
No protein made
Class II?
Protein is abnormal, and destroyed before it reached the membrane
Class III?
Protein reached membrane, but channel is blocked
Class IV?
Protein reached membrane, but channel does not work effectively
Class V?
Protein reaches membrane, channel works but not enough produced
Most common mutation?
Deltaf508 - Class II
What happens when the chloride channel is blocked?
Salt and chloride cannot leave the intracellular space, inhibiting water to follow and created the thick mucus layer as water is trapped in the cell
Why is thick mucus as problem?
Will physically block organs, and exocrine glands and cause inflammation
What organs does the the thick mucus affect?
- Pancreas
- Sinuses
- Reproductive
- Intestines
- Airways in lungs
Why do CF patients often have frequent infections?
Ineffective clearing of mucus, pathogens and bacteria will become trapped
What happens in the sweat glaands?
More NaCl will be excreted, and 2-3 times more sodium is excreted. Can be impacted during hot day’s, fevers, sickness
Symptoms?
- Persistent cough
- Difficulty with growth (Pancreas affected)
- Abdominal pain
- Bloated stomach
- Salty tasting skin
- Clubbing of fingers
What is the main reason for malnutrition in CF?
Pancreatic insufficiency
How does pancreatic insufficiency lead to malnutrition?
Thick mucus blocks endocrine cells, no hormones/enzymes can leave, not uptake of nutrients
What should a CF patient take to combat pancreatic insufficiency?
Oral pancreatic enzymes –> Lipase, protease, amylase
When should oral pancreatic enyzmes be taken?
Just before eating, and amount may need to be increased if eating more
Are enzymes 100% efficient?
No
What is the dosage of pancreatic enzymes based on? Why?
Lipase units (LU), as lipids are the hardest to digest
General recommendation for LU?
500-4000 LU/gram of fat ingested/day
Pulmozyme =
inhaled, thinner mucos
TOBI/Cayston =
inhaled antibiotics, alternate to reduce antibiotic resistance
Bronchodilators and corticosteroids=
Reduce blockage of airways, and reduce inflammation
Multivitamins
Risk of malnutrition and malabsorption, supplements recommended
Vit D and calcium
supplements recommended due risk of osteoporosis
What other supplements are recommended?
-Iron, Zinc, omega-3
Prednisone is often prescribed to reduce inflammation and help breathing, why exert caution?
Bone thinning, impaired glucose control, water retention
What is difficult for Cf patients?l
Compliance with medications (normal for all pulmonary disease)
What are 3 predictors of non-compliance?
1) Long-term treatment
2) Individual is asymptomatic
2) If treatment is complex
What are some complications of CF?
- Frequent infections (hospitalization)
- Nutrient deficiencies (malabsorption)
- GERD
- IBS
- Osteoporosis
- Liver, heart
- CF related diabetes
Why higher risk of osteoporosis?
- Constantly on steroids
- May not absorb all calcium and Vit D from supplements
What is DIOS?
Distal Intestinal Obstructive Syndrome, major complication of CF
Risk factors for DIOS?
- Severe genotype (first 3 classes)
- Pancreatic insufficiency
- Fat malabsorption
- Dehydration
- History of meconium ileus or DIOS
- Organ transplantation
What is meconium ileus?
First stool thats blocked at birth
Symptoms of DIOS?
- Acute onset of sever abdominal pain
- N/V
- Inability to pass gas or stool
Treatment for an incomplete DIOS?
-Oral rehydration with stool softeners and laxatives (PegLyte)
Treatment for complete DIOS?
- IV rehydration
- Nasogastric aspiration
- Enemas, laxatives
- May need surgery
How should we refeed patient after DIOS?
NPO until resolved, and start with clear liquids, full liquids then transition to regular diet
What is the issue with DIOS?
Patient may have up to a week of suboptimal nutrition
Impact on patient after DIOS?
- Anxiety towards food
- Changes in oral enzymes
- Keep track of water/fibre
- Add laxatives
How many Canadians with CF have CF related diabetes?
22.4%
What is the cause of CFRD?
Mucus blocks endocrine ducts of pancreas –> pancreatic insufficiency –> no insulin –> diabetes
What is the standard for detecting CFRD?
Oral glucose tolerance test 1 hour post ingestion
What is another symptom of CFRD?
- Inexplicable decline in breathing
- Inability to gain weight (or weight loss)
What is malabsorbed in CF?
Fat soluble vitamins
CF patients often have low Hgb, Hct, Fe and B12 leading to anemia - why?
- Blood loss (IBS)
- Anemia of chronic disease
Malabsorption of which nutrient causes acrodermatitis enteropathica, severe diaper rash, decreased appetite and delayed growth?
Zinc
Live function tests should be obtained yearly for all patients with CF - what values are indicative of CF related liver disease?
- ALT
- AST
- Alkaline phosphatase
- GGT
Energy requirement is CF is ___ of that of a healthy individual of same age and gender
110-200%
Why are E requirements higher in CF?
- Work of breathing/coughing
- Presence of inflammation
- Malabsorption
- Complications
There is a positive association between ____ and lung function
BMI
If there is rapid weight loss, what may we be concerned about in CF patients?
Decreased lung function
Target healthy BMI females?
2
Target healthy BMI males?
23
Target healthy BMI children?
> 50% percentile
What is the main dietary issue with CF?
Increase E requirement with compounding factors that increase difficulty in eating, decreased appetite and absorption
What influences eating in CF?
-Dyspnea (SOB)
-SInus problems
-Steroids (increase or decrease appetite)
-GI problems
-Slow-intestinal motility
-History of DIOS
Psychological and financial history
What is the paradox in infection on nutrition status?
Decreased appetite while calorie needs are increases, leading to potential weight loss
Nutritional intervention?
- High energy/protein
- Supplements as snack
- Adding enteral to oral nutrition
- Potentially increase sodium
(T/F) There has been a major increase in life expectancy amongst CF patients due to better nutrition and treatment
T
(T/F) Most patients with CF are teenagers
F, due to higher survival rates, 60.9% of CF patients are adults
Median age of survival?
52.3 years
How do new medications act?
On cellular level to help proper folding and insertion into channels
Drugs to treat CF?
- Kalydeco
- Orkambi
- Symdeko
Which drug specifically treats F508del mutation?
Orkambi