Finally diagnosed, a few questions...

[Jenie-Bogard]

  I've recently been diagnosed with DRD(dopa responsive dystonia) after 5 years of increasing disability.I've been in a chair for 3 1/2 years(almost a quadriplegic), mobility/movement problems really began 5 yrs ago, though there were probably some earlier signs that we ignored in childhood and adolesence.   I went to the Mayo clinic in early October and they figured it out in a matter of minutes.  They said that it was an atypical case, but if they were right, the Sinmet would pretty much fix me.
  Now I'm on Sinemet and am able to walk and even run. I was literally walking the day after I took the meds.  Thank God.
  My questions are:
    Is Sinemet a drug that can affect a fetus?  I'm 28, a mom of a 5 1/2 year old, married and a full time pastor in the Lutheran church.  I had almost had a tubal before the diagnosis.  Now that I'm better, I wonder if I could have more kids?  Concerned not so much about genetics of DRD but adverse effects.
  What is the prevalence of DRD?  I understand that it is rare. How rare?
  Does this trreatment wear off after a few years?  Does the condition level off or keep progressing like Parkinson's?  I was basically getting worse during the time I was undiagnosed.  Will this stop the progression of the disease?
  How seriously should I seek to have my daughter assesed(at Mayo)?  She seems fine now, though she does toe walk when she's tired.  I don't want her to miss anything since this is so treatable.
  My doctors here in Chicago have either not heard of this disorder or have little experience with it to answer my questions.  I haven't heard from the Mayo docs either (I've called and written).
  Any suggestions?
  Thanks
  Rev. Jennie Bogard
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Dear Rev. Bogard,
thank you for your question.
Dopamine responsive dystonia (DRD) was first described by Segawa in Japanese
patients, hence the eponym Segawa's disease. In 1993, the first causative
gene for DRD was isolated. It is called GTP cyclohydrolase-1 (GCH-1), I think
on chromosome 14. It is possible to check for this gene for genetic reason.
In the majority of cases, the mode of inheritance is autosomal dominant.
I don't have prevalence number for DRD. I checked in several sources and
none quotes any number. Although it may seem rare, it is most likely
underdiagnosed. Many case reports in the literature especially in children
misdiagnosed as having cerebral palsy or even hysteria.
The course is usually stable on Sinemet. Unlike Parkinson's Disease patients
in whom dyskinesia (involuntary movements) occur with prolonged treatment
(with Sinemet) requiring dose adjustment, in DRD, the patients seem
to be stable on Sinemet, and dyskinesia does not develop.
From several reports in seems like the symptoms return when there is an
attempt to wean off the medication.
As with Sinemet and pregnancy, it is not a known teratogen, although
as you know the main use of sinemet is for Parkinson's disease which affects
older patients. I have not had to use Sinemet in young woman of childbearing
age. I would review the PDR and as with any drug the risk and benefit
must be weighed carefully.
I am glad you finally can live a normal life again. Good luck and please
don't hesitate to post follow up question or information.