Cystic Fibrosis

Question 1

CF is a ______ disease

Answer 1

multisystem progressive

Question 2

CF characterized by:

Answer 2

abnormal Na and Cl and bicarbonate transport across epithelial cells and exocrine glands–>thick mucus secretions affecting rest, pancreas, intestine, hepatobiliary, sweat, repro tracts

Question 3

CF is an ____ genetic disorder

Answer 3

autosomal recessive

Question 4

CF caused by defect in gene encoding ____ on chromosome # ____

Answer 4

cystic fibrosis transmembrane conductance regulator (CFTR) protein ; 7

Question 5

90% of CF patients have mutation in ___ gene

Answer 5

DeltaF508

Question 6

there are ____ classifications of mutations

Answer 6

6

Question 7

class 1 mutation

Answer 7

absent CFTR protein

Question 8

class 2 mutation

Answer 8

protein misfolding

Question 9

class 3/4 mutation

Answer 9

defective CFTR channel regulation

Question 10

class 5 mutation

Answer 10

reduced functional CFTR

Question 11

class 6 mutation

Answer 11

decreased CFTR stability at cell membrane (rare)

Question 12

prevalence in caucasian population:

Answer 12

1:3000

Question 13

prevalence in Africans ____ and Asians ____

Answer 13

1:15000 ; 1:32000

Question 14

tests to diagnose include :

Answer 14

genetic testing/counselling, neonatal screening, measuring trypsinogen (if high, confirmatory test), sweat chloride test, sputum cultures, pancreatic function tests, pulmonary fun test

Question 15

abnormal CFTR causes _______

Answer 15

inadequate Cl reabsorption, so it is retained and traps sodium ions on skin surface

Question 16

gold standard test

Answer 16

sweat chloride test performed on both forearms, measures abnormality of salt in sweat

Question 17

normal values of Cl in sweat chloride test is ___, in “classic” presentation it is > ___ mmol/L

Answer 17

<30 mmol/L; >60

Question 18

respiratory pathophysiology?

Answer 18

sinusitis, cough/wheezing, mucus plugging in lungs, rest infection, bronchiectasis (scarring recurrent inflammations in lung’s airways), pulmonary insufficiency, pulmonary failure

Question 19

pancreas pathophysiology?

Answer 19

secondary to mucus accumulation and blocked ducts, digestive enzymes can’t reach small intestine so malabsorb fat-sol its–>steatorrhea, poor growth, nutrition deficiency, pancreatitis, DM

Question 20

what does healthy pancreas look like?

Answer 20

CFTR channels allow passage of Cl and HCO3 ions into pancreatic ducts, secretions contain digestive enzymes that breakdown pro/fat/cho in small intestine

Question 21

digestive pathophysiology?

Answer 21

can’t fully absorb nutrients –>reduced Cl and H2O secretion –>GERD, meconium ileum (intestinal obstruction at terminal ileum) at birth–> distal intestinal obstruction syndrome (DIOS) later in life –>short intestinal bacterial overgrowth (SIBO)

Question 22

SIBO ^ ____ and v ____

Answer 22

infection ; tolerance to sugars/CHO

Question 23

in CF, pancreatic exocrine secretions have v _____

Answer 23

bicarbonate, pH , volume

Question 24

why osteoporosis in CF?

Answer 24

malabsorption vit D

Question 25

hepatobiliary pathophysiology?

Answer 25

^ viscosity of bile that obstructs hepatic ducts and cause biliary cirrhosis, inflammation, scarring, fibrosis –> blocked ducts and impaired bile flow/bile acid metabolism, v total bile salt pool –>gallbladder inflammation and gallstones

Question 26

sweat pathophysiology?

Answer 26

elevated sweat chloride–> abnormal CFTR inhibits reabsorption of Cl from sweat into cells lining sweat duct –> retention of chloride traps Na on skin surface

Question 27

reproductive pathophysiology?

Answer 27

males 98% infertile cuz abnormal development vans deferens in utero (dysfunctional CFTR channels on surface of sperm, mucus, atrophy); females have v fertility cuz of comorbidities of poor nutrition and inadequate CF diabetes mngmt

Question 28

BMI < or > sensitivity to lung function than %IBW?

Answer 28

>

Question 29

BMI recommendations for men/women and ppl < 21:

Answer 29

women maintain a BMI of at least 20, ideally 22 and men, a BMI of at least 23. For people under age 20, BMI should be at or above the 50th percentile on the CDC growth chart

Question 30

goals for nutrition status:

Answer 30

normal fat sol vitamin and micronutrient status, EFAs monitored

Question 31

nutrition goals include:

Answer 31

promoting optimal growth, muscle strength, wt maintenance, enhance quality of life

Question 32

why increased energy requirements?

Answer 32

pancreatic insufficiency, lung function deteriorating causes increased workload, lung infection

Question 33

why reduced absorption?

Answer 33

pancreatic insufficiency: SIBO, CF-related liver disease

Question 34

why inadequate intake?

Answer 34

anorexia, GERD, DIOS (constipation), psychosocial, med side effects

Question 35

protein requirements:

Answer 35

1.5-2x DRI for age

Question 36

fat requirement %:

Answer 36

35-40% kcal

Question 37

which equation to calculate Daily Energy Expenditure?

Answer 37

WHO equation with activity and disease coefficients

Question 38

pancreatic enzyme supplements contain:

Answer 38

lipase, amylase, protease

Question 39

what is the function of pancreatic enzyme therapy?

Answer 39

digest CHO/pro/fat; assist with wt gain, promote nutrient absorption

Question 40

enzymes taken ___ and ____ all meals and snacks

Answer 40

before; during

Question 41

small children mix beads with ___

Answer 41

applesauce

Question 42

how know if enzyme dose correct?/

Answer 42

healthy wt gain, less stools

Question 43

which foods not require enzymes?

Answer 43

fruit snacks, fruits, juices, popsicles, jello, sports drinks, sugary items

Question 44

why caution with 10 000 lipase units/kg/day for all ages?

Answer 44

fibrosing colonopathy

Question 45

why malabsorption of fat sol vitamins?

Answer 45

patients lack bile so cannot produce adequate bile salts due to Cl channels blocked with thick mucus and clogging liver where bile produced, difficult absorb vitamins

Question 46

adequate Na reduces:

Answer 46

headache, fatigue, poor concentration, salt crystals on skin, muscle cramps, hyponatremia, nausea, v appetite

Question 47

additional Na may be needed based on:

Answer 47

activity lvl, climate, diet intake, symptoms

Question 48

calcium requirement is ___ mg/day

Answer 48

1500

Question 49

why low BMD?

Answer 49

medications (glucocorticoids), malnutrition/malabsorption, inflammation, inactivity

Question 50

why delayed growth and puberty for CF ppl?

Answer 50

hormone levels affected with CF

Question 51

phosphorus homeostasis regulated by ____, magnesium absorption is abnormal in ____, magnesium excretion is ^ cuz ____, iron is ___, zinc is needed for ___

Answer 51

vit D; pancreatic insufficiency ; antibiotics; often deficient; support other nutrients to promote growth, maintain appetite, fight infection

Question 52

examples of meds:

Answer 52

targeted to specific mutation as CFTR potentiator and corrector; oral pancreatic enzymes, mucolytic agents, antibiotics, anti-inflammatory, bronchodilators, insulin

Question 53

if BMI for age - growth charts < ___ percentile can identify nutrition risk

Answer 53

10th

Question 54

last therapeutic option, end-stage lung disease

Answer 54

lung transplant

Question 55

nutrition intervention post transplant:

Answer 55

promote wound healing, treat electrolyte imbalances, achieve optimal BG control