Doubtful sweat tests- continued

Question

I would like to thank you for your first reply. [comment of the ECORN-CF team: for better understanding of this question, please see former question and answer in the additional comment field below].
Regarding your questions, I and my husband were tested before having children, because my cousin’s daughter has CF. During my first pregnancy (2005) I had a CVS testing and the sample was send to the TDL GENETICS lab, in the UK, where it was examined for 33 mutations. My daughter was tested due to growth issues and the relative medical history when she was 3 years old at the genetics lab of Heraklin University Hospital for 29 mutations. My husband has been tested for 86% of CF mutations at the Horemio lab- Department of Genetics, Aghia Sofia Hospital. All sweat tests have been performed at Heraklion University Hospital. I do not know which methods were used. I should add here the test with the lowest values was done in 2005, whereas the rest of the tests were done 5 years later.
Where can a full genotype testing be performed? Should we repeat the sweat tests? Do you think that we should visit the Aghia Sofia Hospital?

Answer

Dear friend,
At first opportunity, I strongly suggest that you have the sweat test performed for both your daughters at the CF Center at Aghia Sofia Children’s Hospital, which uses the pilocaprine method and performs more than 1200 such tests on an annual basis.
A full genotype testing can be performed at the Horemio Laboratory- Department of Genetics, Aghia Sofia Hospital, as well as in other laboratories.
Yours friendly,
Dr. Stavros Doudounakis

27.10.2011

27.10.11 To be able to understand the actual question, here is a copy of the former question to which the questioner referrs to:
Doubtful sweat tests
Question
I have two daughters, 4 and 6 years old. Both are carriers of the W1282X CF, mutation, as I am, whilst my husband is negative. Their health in general is good. The values of their sweat tests are borderline. The older one has been tested 3 times (values 25.2-55.5-38.3), and the younger one twice (values 42.1-55.9).
I am really worried and I do not know if I must have them tested in some other way. Could these elevated values be attributed to them being carrriers?

Answer
Dear friend,
Before I try to answer your question I would really like to know the following:
a. Why were you tested for CF mutations, after which you were found to carry the mutation W1282X?
b. Where were the sweat tests performed and which method was used (or were there different methods used?) As the values can only be interpreted by us or used as a vaild tool if the test was performed in an experienced center and measured the Chloride concentration of the sweat with pilocaprine ionotophoresis.
c. How many mutations were your husband and daughters tested for?

In any case your older daughter, for whom three sweat tests were performed, has two normal result values (assumed that they were measured as described above) and one intermediate value and, clinically speaking, in general she is fine. Based on the above I do not think she has something, but simply is a carrier of a CF mutation.
Your younger daughter, who had two sweat tests, has two intermediate result values and in general is quite well without any symptoms. In her case I recommend to have one more sweat test performed, as well as a comprehensive genotype testing, if it has not already been done, since it is quite possible that your younger daughter is a carrier of a CF mutation, or has an atypical, mild form of the disease.
Yours friendly,
Dr. Stavros Doudounakis

04.10.2011
D. d'Alquen