Flashcards in Cystic Fibrosis Deck (15)
What signs maybe found on examination of a patient with cystic fibrosis?
Bilateral coarse crackles
Decreased body weight/failure to thrive
What is needed for a diagnosis of cystic fibrosis?
One or more characteristic phenotype features OR a CF sibling OR a positive newborn screening test result
Sweat test OR two CF mutations from genotyping OR nasal potential difference
A common presentation of CF is meconium ileus, what is meant by this?
15-20% new burns
Bowel is blocked by sticky secretions
Signs of intestinal obstruction soon after birth with bilious vomiting, abdominal distension, and delay in passing meconium
A common presentation of CF is intestinal malabsorption, what is meant by this?
Over 90% of patients
Main cause is a severe deficiency in pancreatic enzymes, can be given as replacement therapy in the form of Creon - with all meals and snacks
Fat soluble vitamin supplements (ADE)
High calorie intake needed 150% daily calorie intake
Overnight feeding via gastrostomy is increasingly used
What are the complications of CF?
Low body weight/failure to thrive
Distal intestinal obstruction syndrome (DIOS) - meconium ileus equivalent
CF related diabetes (pancreatic insufficiency)
Male infertility - can father children through ICSI (intracytoplasmic sperm injection)
Rectal prolapse - due to bulky stools
What is meant by distal intestinal obstruction syndrome (DIOS)?
Faecal obstruction in the distal ileum and proximal colon
Most often due to insufficient prescription of pancreatic enzymes or non-compliance, also salt deficiency/hot weather
Often presents with palpable RIF mass
Managed with gastrograffin
What lifestyle advice is given to patients with CF?
Avoid other CF patients/people with colds/infections
Avoid jacuzzis, stables, compost
Annual influenza immunisation
Sodium chloride tablets in hot weather/exercise
What happens in the management of CF?
Regular physiotherapy - chest clearance at least once a day, twice if they are unwell/have a cough to help clear secretions
Abx (infections associated with Burkholderia cepacia)
Mucolytics eg Nebulised DNAase - given at least one hour before chest clearance exercises
Nutrition, Creon and vitamin supplementation
What is the result of a sweat test in a CF patient?
An increased sweat chloride concentration >60mmol/L
What is meant by cystic fibrosis?
An autosomal recessive disease leading to mutations in the CFTR on chromosome 7. This leads to multi-system disease characterised by thickened secretions commonly affecting the respiratory and GI tracts.
Many mutations have been identified. F508 mutation is the most common
What happens in a newborn screening test?
Heel prick test aka Gurthrie test at day 5
IRT (immunoreactive trypsinogen) to detect CF (will be raised)
If positive, screened for common CF mutations
If two mutations detected, sweat test to confirm the diagnosis
How can pancreatic dysfunction be assessed in patients with cystic fibrosis?
Exocrine - faecal elastase
Endocrine - annual glucose tolerance test
In cystic fibrosis, different micro-organisms are the most likely causes of infection. Outline the different micro-organisms at different stages
1 year - h.influenzae - causes local lung damage
2-3 years - staph a
3-10 years - pseudomonas auerginosa, burkholderia cepacia
Teens to twenties - atypical mycobacteria, Candida albicans, aspergillus fumigatus
What is the presentation of a pseudomonas infection?
Characteristic green sputum because the micro-organism produces a blue-green pigment
Chronic wet cough
Treat with Ciprofloxacin