Cystic fibrosis - carriers and affected

Question 1

Explain to patients with positive CF carrier status what CF is and what is their risk of having a child with CF

Answer 1

• CF is a genetic condition where a faulty gene results in impaired movement of salt and water in and out of cells.
• This causes a build up of thick sticky mucus in various organs leading to dysfunction.
• It can affect: lungs, pancreas.
• It is a condition that reduces life expectancy; 50% of people will live past 40 years old.
• If both parents are carriers:
  
  • 50% chance child will be a carrier
  • 25% chance child will have CF
  • 25% chance child will not have CF and not be a carrier.
• If one parent has CF and one parent is a carrier:
  
  • 50% chance child will have CF
  • 50% chance child will be a carrier

Question 2

Counsel a woman with CF on pregnancy and management

Answer 2

• Maternal risks: deterioration in lung function, GDM, pneumonia, congestive heart failure, CS, mechanical ventilation, death.
• Fetal risks: PTB, IUGR, SB

Comorbidities complicating pregnancy: pulmonary HTN, poor nutrition

Booking:

• MDT
• Review lung function
• +/- ECHO
• Vaccinations
• Dietician

Antepartum:

• Serial growth scans
• Regular follow-up with MDT.
• Early OGTT
• Anaesthetic review

Intrapartum:

• CS only for obstetric indications.
• Avoid general anaesthesia if possible. Early epidural.
• Limit second stage; increased risk of pneumothorax