Tests for brother and sister

Question

I have three children. The youngest has Cystic Fibrosis. Is it necessary to test the elders who are 6 and 4 years? They have no symptoms and their skin is not salty. Can they declare the disease later ? Cordially.

Answer

Hello,
Your question about the health of your children is legitimate. CF disease was formely named "the kissing salted disease", but the simple taste of the skin can not confirm or refute the diagnosis. CF neonatal screening was performed in France since 2002. Your children, 4 and 6 years old have been screened, if they are born on French territory. Screening is done from the blood sample on filter paper realized on the third day of life at the birthing clinic.
The likelihood that your children are suffering from cystic fibrosis is very small and you have no reason to worry, especially since they have no symptoms. However, to confirm and reassure you, you can request to perform a sweat test to your two children. Talk to your referring doctor at the CF centre.
Cystic fibrosis is a genetic disease present and diagnosed today at birth, it cannot be acquired during life. However, in general, there are some forms of CF (milder ones) where symptoms develop later in life even if the mutation is present from birth on and if there is no neonatal screening, those cases are diganosed later in life.
However, your children can be "healthy carriers" of a mutation of cystic fibrosis. They may, once adults, receive genetic counseling. (See also the question on this site "Cystic Fibrosis carrier")
I hope that answers your request
Sincerely
Marythé Kerbrat

07.05.2012