Cystic Fibrosis

Question 1

1 in ___Canadians is a carrier of a
CF mutation

Answer 1

1 in 25 (to 30) Canadians is a carrier of a
CF mutation

Question 2

Describe the genetics in CF

Answer 2

CF is autosomal recessive, most common in those with european descent.

Question 3

CF is ___ recessive, most common in those with european descent.

CF gene is foundon chromosome ___ as the ___ gene. the ____ gene is the most common mutation.

Answer 3

CF is AUTSOMAL recessive, most common in those with european descent.

CF gene is found on chromosome 7 as the CFTR gene. the DELATF508 gene is the most common mutation.

Question 4

Class types of CFTR mutation

Answer 4

different class affect different cell aspects

Class1: protein is no synthetized at all

Class2: protein is synthesized but does not make it to eh membrane

Class3: channel gets to the membrane but cannot activate

Class4: channel can function normally but it doesn’t last very long. acceleated turn over

Class5: normal channel but just reduced synthesis

Class6: different channels effected

Question 5

types of Testing for CFTR Mutations

Answer 5

• Standard panel testing – top 69 most common mutations in Alberta
• Extended panel testing

• CFTR sequencing
( Challenges with interpretation )

Question 6

Abnormal CFTR consequences

Defective __ transport on __ cell
membrane, and enhanced __ absorption
through epithelial ___ channels (ENaC)
and basolateral __/_ ___ pumps

Net effect: less water to ___ layer,
impaired mucociliary clearance, ____,
infection

Answer 6

Defective chloride transport on apical cell
membrane, and enhanced sodium absorption
through epithelial sodium channels (ENaC)
and basolateral Na/K ATPase pumps

Net effect: less water to mucociliary layer,
impaired mucociliary clearance, inflammation,
infection

Question 7

outline the sweat test procedure and what results would indicate CF

Answer 7

sweat test is the diagnosis for CF.

• they do pilocarpine stimulation on forearm
• sweat chloride level is HGIH in people with CF >60mmol/L
• normal is <30 in infants, <40 in older
• gray zone results are problemtaic.

Question 8

Explain CFTR function in the sweat gland

Answer 8

in sweat glands, the channel is reversed. Cl normally tries to go into the extracellular space, but sweat glands try and absorb Cl INTO the cell. in people with CF, there are deficinet Cl channels everywhere including the sweat glands, and so the CL stays in the sweat because the channel cannot bring it back into the cell.

Question 9

common presentations of CF

Answer 9

Acute or persistent
respiratory symptoms

 “asthma”

 “cough” “wheeze”

 “bronchitis

 Nasal polyps/sinus
disease

 Failure to
thrive/malnutrition

 Steatorrhea/abnormal
stools– can’t absorb fat from their diet.

 Formula intolerance

 Colic  Food intolerance
 Newborn screening
 Neonatal screening

Question 10

less common presentations that are red flags

Answer 10

rectal prolapse, meconium ileus, bowel obstruction, family history, appendicitis, fat-soluble vitamin insufficiency, electrolyte imbalance.

Question 11

finger issues in CF

Answer 11

clubbing is seen

Question 12

treatment for nasal polyps

Answer 12

usually steroids, sometimes antibiotics

Question 13

CF: lung involvement

 Chronic endobronchial __

 Chronic endobronchial neutrophilic
__

 __ airway disease

 ___

Answer 13

 Chronic endobronchial infection

 Chronic endobronchial neutrophilic
inflammation

 Obstructive airway disease

 bronchiectasis

Question 14

4 key managements of CF lung disease

Answer 14

1. nutrition
2. chest physiotherapy
3. enhance mucus clearance via hypertonic saline inhalation
4. antibiotic therapy during exacerbations

Question 15

methods of chest physiotherapy to help with airway clearance

Answer 15

Question 16

most common bug that cause lung infections in person with CF

Answer 16

most common is staph aureus. treatments are often for fram positive bugs, and do cultures.

• when you get older with CF, the less common bugs become more common too

Question 17

pulmonary complications of CF

Answer 17

 Hemoptysis

 Pneumothorax

 Nocturnal hypoventilation

 End stage lung disease

Question 18

treatment/management of end stage lung disease

Answer 18

1. lung transplant
2. non-invasice ventilatory support X

Question 19

main pancreatic problems in CF

Answer 19

• pancreatic insufficiency
• causes malabsorption of fat and protein, as well as fat soluble vitamins
• also a loss of bicarbonate and water secretion into duodenum to assist with absorption

Question 20

how do you monitor pancreatic functon in people with CF

Answer 20

• stoolfrequency and quality
• abdominal pain
• growth and weight gain
• fecal elastase to assess pancreatic sufficiency
• fat soluble vitamin levels ADEK

Question 21

Pancreatic enzyme replacement

Answer 21

Question 22

why is there CF related diabetes

Answer 22

• because there is a decline in pancreatic islet cell function with age.
• may see weight loss, decling in pulmonary function.
• must use insulin

Question 23

The CF gut:

5-10% of babies with CF present with
___ ileus at birth

in children, ___ is common.

___ ___ ___ ___ (DIOS) is a condition where thick fecal material plus mucoid material adheres to the bowel wall.

Answer 23

5-10% of babies with CF present with
MECONIUM ileus at birth

in children, CONSTIPATION is common.

DISTAL INTESTINAL OBSTRUCTION (DIOS) is a condition where thick fecal material plus mucoid material adheres to the bowel wall.

Question 24

TREATMENT FOR CONSTIPATION AND DIOS

Answer 24

• hydration
• osmotic laxative PO
• NG decompression
• NG gastrograffin
• surgery in extreme cases

Question 25

first sign of CF liver disease

Answer 25

first signi s LFT elevation. May also see difficulty in absorption of fats. consider ursodeoxycholic acid to improve clearance of bile salts from ductules.

Question 26

Fertility in CF

 Males infertile
occlusion of __ __ (congenital absence)

 Females have reduced fertility, due to
quality of __ __
severity of lung disease
_ status

Answer 26

Fertility in CF

 Males infertile
occlusion of vas deferens (congenital absence
of the vas deferens)

 Females have reduced fertility, due to
quality of cervical mucus
severity of lung disease
nutritional status

Question 27

outline the CF newborn screening protocol in Alberta

Answer 27

you first do a blood spot and sent for metabolic disease function including CF. looking for IRT protein related to the panceras. Is often elevated in CF and in carriers.

Question 29

note; complications increase with age. it’s no longer a pediatric disease now that there are better treatments

Question 30

note; new meds

Question 31