Hi,

I am sorry you are going through this. It's scary enough to face having Parkinson's in the first place let alone not being sure what the heck's going on. Often, a MDS will issue a "dopamine challenge" to see if a patient responds to dopamine. Also, and MRI is given to rule out any other brain abnormality. There is no definitive biochemical test for Parkinson's, so we're really dependent upon the skill, experience, instinct, whatever of the neurologist.

In taking levodopa, I think you are right that you should have a more immediate response with any sort of dopamine deficiency. However, we don't all respond to medication the same way; some do not respond well to levodopa though they seem to have Parkinson's. Likewise, people have been diagnosed, responded to meds, and upon autopsy (this is the only definitive diagnosis for idiopathic PD, gruesome, I know) did not have Lewy bodies, the hallmark of the disease.

I think the SPECT scan should help tip the scales in your diagnosis. If there is indeed a dopamine deficiency, it will show on the scan. From there, I would seek a second opinion no matter what the scan shows just to be sure given your reaction to the levodopa trial. Diagnosis of early PD, from what I've read, is difficult as the symptoms mimic those of other things.

If it is PD, try to limit the stress (easier said than done, I know) as it ramps up your symptoms, which in turn makes you more stressed, till we come to a full vicious circle.

Hang in there!

Laura