No problems

[Bridgetjulia]

I'm wondering if any of you know people with Cystinuria who have never had stones or any problems at all, really?
The only reason I know I have it is because the hospital tested my urine and DNA when I was an infant. Otherwise, I don't think I'd have really realized.
It seems unfair, but I've never had a problem with it yet. I was told I have "type I/III Cystinuria".
What's up?

Bridgetjulia

[Matt Lewis]

Well you bring up a good point; not all people with cystinuria will form stones. I personally do not know of anyone with the disease who doesn't form stones, largely because most people discover it when they have their 1st stone, it is analyzed, and the results confirm that it is composed of cystine.

To start with your parents, they are statistically most likely to be heterozygotes for the disease (carriers). According to an abstract titled SLC7A9 mutations in all three cystinuria subtypes, (link here (http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12371955&dopt=Abstract)), the heterozygous parents of Type I children will be completely silent carriers with no abnormal cystine levels. The parents of type 2 will have a large elevation in cystine concentration and parents of type 3 children will have a moderate elevation. It sounds like your doctors concluded that one of your parents was a carrier for type I and another was a carrier for type III? If that is the case, i think this classification system might be too rigid for you.
Normally, however, the people with type I are the most likely to form stones, even though their parents show the least of all symptoms. It is my understanding that types II and III, while more serious for parental carriers, are less serious for the affected children.
This is just the way i understand it. I'd be interested in hearing other opinions! :)
matt