Cystic Fibrosis Flashcards
CF displays what kind of inheritance pattern?
What PT demographic is most commonly observed w/ CF?
Autosomal Recessive (a defunct CFTR gene on chromosome 7)
Caucasians
The CFTR (Cystic Fibrosis Transmembrane Regulatory) gene is responsible for what physiologic function?
If defective CFTR gene is passed to offspring; how does this impact them clinically?
CFTR regulates CAMP-chloride transport channels on mucosal surface
Results in increased viscosity of secretions which are difficult to clear
Because of the altered CFTR gene function; what lab could help you clinically Dx CF?
SWEAT CHLORIDE! >60mmol/L (due to the altered CAMP-chloride transport; upreg)
If neg. sweat chloride; run DNA analysis to assess for non-classic CF (<2% of cases; but occurs)
What is the clinical presentation of a PT with CF neonates?
Meconium Ileus (obstruction of bowel by meconium)
Intestinal atresia (intestinal blockage from stenotic intestine)
Volvulus (Intestine wraps around itself, strangulates itself causing bowel obstruction)
What is the clinical presentation of a PT with CF <1 year of age?
Recurrent respiratory infxn or pneumonia
Wheezing and coughing
Steatorrhea (Oily/fatty stools)
FAILURE TO THRIVE
Physical Exam of a CF PT might yield…
Clubbing Tachypnea, wheezes, crackles Abdominal Distention Hepatosplenomegaly Rectal prolapse Aquagenic Palms (wrinkled appearance) Signet ring sign on CXR Lung Hyperinflation on CXR PFT's suggesting (OBSTRUCTIVE Dz) Musculoskeletal: Scoliosis, kyphosis, lymphadenopathy (parotids or submand.)
Recurrent bronchitis in CF patients may lead to which clinical condition?
Bronchiectasis w/ signet ring sign
Airway infections are most commonly observed with which microorganisms most commonly?
Staph aureus
Gram neg. bacteria
ULTIMATELY PSEUDOMONAS
T/F
Pancreatic and Sinus involvement does not typically occur in CF PT’s but may present in more severe cases.
FALSE
Sinus and pancreatic insufficiency are COMMON!!!
What are some of the possible Pancreatic manifestations of Cystic Fibrosis?
Steatorrhea (fatty/oily stool) –> malabsorption of fat can lead to F2T
Abdominal Distention
Deficiencies of Vit ADEK
Pancreatitis
CF related Diabetes
Why do abdominal/GI Px complaints with a CF PT need to be appropriately worked up? What might they be at higher risk of?
Small bowel obstruction ~or~ Distal Intestinal Obstructive Syndrome (DIOS)
May require surgery if not caught early enough
T/F
The liver may be cirrhotic in CF patients?
TRUE
3rd leading cause of liver transplant for late childhood patients
What musculoskeletal manifestations may present with CF patients?
KYPHOSCOLIOSIS
Reduced bone mineral density (order DEXA) if repeated Fx
CF patients require counseling for future family planning because…
> 95% of male CF patients are infertile due to dysfunctional sperm motility
What are the common systems impacted by CF?
Sinuses Lungs Skin: Salty/sweaty Liver Pancreas Intestines Reproductive organs
What is the criteria to make a CF Dx?
Clinical S/Sx of 1 impaired organ system, newborn pos. screen, or genetic test pos. of sibiling
Evidence of CFTR dysfunction
- Elevated SweatChloride x 2
- 2 CFTR mutations (one each allele)
- Abnormal nasal potential difference
What does a newborn screening include in the US?
Two assays
Serum Immunoreactive Trypsinogen (IRT)
DNA analysis for CFTR
Sweat chloride levels above what level indicate CFTR testing should be performed?
> 60mmol/L
obtained via pilocarpine
If you have a CF PT; what specialists should you ensure they have on board as their “case manager’?
Pulmonologist Gastroenterologist Surgeon Endocrinologist Otolaryngologist Cardiologist Transplant Surgeon
Acute exacerbations can be managed with what medications?
Inhaled bronchodilators: Albuterol
Chest physiotherapy
Mucolytic: Dornase Alfa (Pulmozyme)
Oral Abx: Fluoroquinolones
To manage failure to thrive, fatty stools (steatorrhea), etc. what would you Rx your PT?
Pancreatic enzymes (not to exceed 2000 units /kg /meal)
Vitamin Supplements
Mucolytics you can Rx a CF PT include???
Dornase alfa
Acetylcysteine (Mucomyst)
CFTR Potentiators: (L-I-T)
Lumacaftor/Ivacaftor
Ivacaftor
Tezacaftor/Ivacaftor
Antibiotics will be necessary to control CF patients recurrent infections. What are 3 of the more common microorganisms which infect CF patients and what would you use to Tx them?
H. influenzae: Chloramphenicol, CEPHALOSPORINS, Piperacillin IV
Pseudomonas: CEPHALOSPORINS, Fluoroquinolone (Cipro), Piperacillin, Aztreonam
S. Aureus: Cephalexin, Cipro, Chloramphenicol, Bactrim
Tobramycin or Gentamicin can also be given for resistant infxns
