Does an ICM (intestinal current measurement) make sense?

Question

Dear ladies and gentlemen,
there is an adolescent patient, who has had a sweat test result in the borderline area at a CF center and in a second experienced CF center the sweat test results were as well in the borderline area (chloride concentration in the sweat with pilocarpine ionotophoresis) and whose sequence analysis of the CFTR gene as well as a TEPD measurement were normal. Nevertheless, the pediatrician is suspecting the illness of CF, not in the "classical sense" (there is no pancreatic insufficiency underlying), because of the picture of the illness (frequent infections, frequent bronchitis, permanent production of sputum (also in infection-free periods), loss of energy, unwanted weight loss (in the mean time underweight), biliary reflux gastiritis) - does it in your opinion make sense, to have in the end also an ICM (intestinal current measurement) done, in order to safely exclude the illness of CF? The CF center says it is through with the topic CF. As in this center they also thought of a possible PCD (primary ciliary dyskinesia), a high-frequency video-microscopy had been done there, which had to be controlled. We have been sent to an experienced university hospital, that is investigating PCD at the moment, however according to them, it is not very probable that a PCD is underlying.
Now a gastro-esophageal reflux has been diagnosed (via pH measurement) and an anti-reflux operation is considered.
I emphazise, that we have been very content everywhere. My questions arises only from the sorrows that are caused by the long illness history of my child .
Many thanks for your answer.

Answer

Hello,
a classical form of CF is excluded. However, there are additionally to the chloride channels also other channels, that have an influence on the composition of the ariway secretions. With the ICM (after a biospy of the rectal mucosa) it is possible to quantify this ion flow. An atypical CF can be confirmed with this method. I would recommend such an investigation.
Best regards,
Olaf Eickmeier

16.04.2016