My daughter is 16 months old. We found out she had type 1 diabetes when she was eight weeks old. She also has hypothyroidism. Since she has been having orange, greasy stools and not growing well, her doctor ordered a sweat test for cystic fibrosis, which came back borderline. She is having a repeat test done on February 3, 2005. What is the chance she has cystic fibrosis? I am really not sure what borderline means.

Being diagnosed with diabetes mellitus at age eight weeks is pretty atypically early. There are neonatal forms of diabetes, which are very rare, due to a genetic defect, that are often actually transient.

If your child is also being assessed for possible cystic fibrosis (CF), then it brings to mind the possibility that the child has some more global pancreatic insufficiency.

CF is a genetic disorder that actually is one of the more common inherited conditions. About 1 in 20 people (Caucasians) carry an abnormal gene to lead to CF. In order for a child to have CF, BOTH parents have to be carriers, typically. This doesn’t mean they have CF, but are carriers of it.

In CF, there is typically insufficiency of many aspects of producing “secretions” so children with CF are at risk of increased pneumonia and are at risk of poor digestion of food, as the pancreas, in addition to making insulin, makes “digestive juices” to breakdown proteins, sugars, and fats. This then leads to having irregular, typically loose, foul, greasy stools. People with CF typically have a higher proportion of salt in their sweat so the first step in consideration of CF is to do “a sweat test” to analyze the sweat chloride level.”Borderline” probably means the level was at the upper range of expectation. A follow-up could include repeating the sweat collection or performing a more sophisticated genetic/DNA analysis. CF patients can develop a variation of type 1 diabetes (but NOT associated with antibodies), but the diabetes usually develops after the puberty.

If the child has been born with an irregular pancreas, that could explain the early onset diabetes and the stool characteristics you describe. If your child has not been seen at a children’s hospital or university setting, you might want to ask for a referral.

DS