Cysts of the pancreas

Question

My son has cysts on his pancreas and his sweat test result was 53.

What does that mean?

Answer

Dear questioner,
sweat tests are used to diagnose cystic fibrosis (CF).

First, it depends on where and how the sweat test was performed; only pilocarpine iontophoresis at a certified CF center is reliable, and then the following threshold values ​​apply:
A chloride concentration below 30 mmol/L is normal; a chloride concentration between 30 and 60 mmol/L is in the borderline area; above 60 mmol/L it is pathological;

If only a conductivity measurement was performed, the value is not reliable, and different threshold values ​​apply.

Therefore, if the value was determined according to the above criteria, it would be in the borderline area; in that case, the sweat test would have to be repeated. If the value is still in the borderline area, or if there are clear clinical indications of cystic fibrosis (CF), CFTR genetic testing should be performed, as in addition to classic cystic fibrosis, there are also milder forms, so-called "CFTR-associated disorders," which can, however, develop into cystic fibrosis over time. Ideally, a complete gene sequencing should be performed; if abnormalities are found that suggest a disease, the patient should be referred to a specialized center.

Regarding the cysts in the pancreas: yes, cysts can occur in the pancreas in cystic fibrosis. In classic CF/cystic fibrosis, patients have pancreatic insufficiency, poor growth, and fatty stools. This should be investigated by measuring elastase levels in stool samples.

Has such a measurement been performed? Why was the sweat test performed? Was it solely due to the pancreatic findings, or are there other typical CF symptoms such as frequent bronchitis, chronic productive cough, upper respiratory symptoms, or failure to thrive with fatty stools? What were the results of the newborn screening?

As you can see, it's not so simple to say; a diagnosis requires a combination of many tests and findings.
I hope this has been helpful.
Sincerely,
Daniela d'Alquen

20.02.2026