Suddenly CF?

Question

Dear expert team,
I suffer from severe asthma, resistant to any therapy, so is the diagnosis named at least.
However, I have much mucus for a longer time and have much cough, besides the “familiar” episodes of dyspnea. Now a CT of the lungs had been done at the university hospital and bronchiectasis had been discovered. What is that in detail? Now also a sweat test had been done, that was also positive. I am quite young, however I thought that CF is diagnosed right after birth? I have frequent infections with phlegm in the sputum. Can this be correlated with the supposed CF? My lung function is getting worse and worse by the infections and it takes a long time until it is getting better. Is this typical for CF?
Many thanks in advance and best regards,

Answer

Dear questioner,
CF can be diagnosed at any age. In case of patients with milder courses it can happen, that one thinks about this diagnosis at a later timepoint and that a corresponding diagnostics is initated only later. The gold-standard for assurance of the diagnosis of CF is the sweat test, that has to be performed correctly however and from which further diagnostic steps have to be derived.
In connection with your request, I can point to the guidelines for the diagnosis of CF. This is a S2-consensus guideline "Diagnosis of CF" (German AWMF 026-023; in German) under the leadership of the society for pediatric pulmonology dated 06/2013. On page 20 of the guideline there is an algorithm for the procedure in case of clinical suspicion for CF.

In the comment on the algorithm it can be read:
"In case of clinical suspicion of CF, the sweat test is the first line of the diagnostic algorithm. In case of sweat chloride ≥ 30 mmol/l or a sweat conductivity ≥ 50 mmol/, respectively in case the sweat test could not be performed successfully or in case of - if available - positive newborn screening, further diagnostics should be done at a CF center.
In case the sweat chloride value is between 30-59 mmol/l, a CFTR genetic investigation, a NPD and/or an ICM are necessary. The investigation of the most frequent CFTR mutations should be done as the next following investigation due to the good availability and the fast results obtained. In exceptional cases a complete investiagtion of the CFTR gene can be sensible without a preceeding investigation of the most frequent mutations, if otherwise due to the ethnic origin of the patient the detection rate is expected to be very low. In case of lacking confirmation of the diagnosis the next steps would be the CFTR complete analysis and the electro-physiological investiagtions NPD and/or ICM. The order of performance depend on the availability of the methods. A complete analysis of the CFTR gene should also be done in case of patients with a normal electrophysiological investiagtion, as in single cases patients have been described with two illness causing mutations in spite of a normal electrophysiological investiagtion. Conversely, patients, who did not show two illness cauing muations in the complete analysis of the CFTR gene, should undergo electrophysiological investiagtions. For the algorithm in case of CFTR-associated diseases we point to the differentiating algorithms in the Euroepan Consensus document".
Your complaints like productive cough, increased susceptibility for infections and the finding of bronchiectasis also occur in CF, however are not pathognomonic for the illness (in medicine we name symptoms to be pathognomonic if they alone are already sufficient for a secure diagnosis finding). Therefore, in your case respective diagnostic investigations should be initiated anyway. We recommend to present yourself with your positive sweat test result and all other results at a CF center with adult care. Your general practitioner can help your to find such a center, or you visit the Internet page of the German patient association Mukoviszidose eV, where adresses of CF centers are published [muko.info/forschung/public-reporting.html]

I hope to have helped you with my remarks and stay with best regards
Yours Dr. med. Christina Smaczny

28.07.2015