HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

Correspondence to:

ARTICLES: William C. Koller and Winona Tse Unmet medical needs in Parkinson’s disease Neurology 2004; 62: 1S-8S [Abstract] [Full text]

Correspondence: Submit a response to this article

Correspondence published:

Untitled

William C. Koller, Kelly E. Lyons   (17 May 2004)

Untitled 17 May 2004
William C. Koller, Mount Sinai School of Medicine 1 Gustave L. Levy Place New York, NY 10029, Kelly E. Lyons Send Correspondence to journal: Re: this article william.koller{at}mssm.edu William C. Koller, et al.	Dr. Chu raises several important issues regarding the diagnosis of toxin-induced parkinsonism. To address his specific questions: 1. As stated in table 1 the mean years of exposure in these patients was 25.2 years. More specific exposure data was not presented in detail in our paper, as this was a pharmacological study. Most of the patients were no longer working therefore measuring manganese in the blood or urine or obtaining an MRI scan would be of no value. We agree that neuroimaging of the dopamine system would most likely be helpful in the differential diagnosis. However there is minimal data for neuroimaging in manganese intoxication and what exactly there studies would tell us is uncertain. However if a fluorodopa PET scan is normal the diagnosis of Parkinson’s disease would be unlikely. 2. We also believe that this is a broad spectrum of clinical phenotypes for the various forms of parkinsonism. Regarding our paper we feel confidently that one of the authors (WCK) can recognize parkinsonism. The diagnosis of manganese induced parkinsonism was a presumptive one, as stated, for the purpose of the study. We used the term parkinsonism in welders as a descriptive term. We also acknowledged the diagnostic uncertainty in these patients 3. We agree the diagnosis of different types of parkinsonism may be difficult. There are few biomarkers that are useful in this regard. This is in fact why we did this study to see if levodopa responsiveness can be useful in separating various forms of parkinsonism, which if fact it appears to be, as Dr. Chu has reported previously.1 4. Lastly a case of parkinsonism due to manganese in a welder has been reported which addresses many of the diagnostic concerns of Dr. Chu .2 Finally we agree that more scientific investigation is necessary regarding toxins that cause parkinsonism. References 1.Lu, CS, Huang, CC, Chu, NS, Calne, DB. Levodopa failure in chronic manganism. Neurology 1994; 44:1600-1622 2.Sadek, AH, Rauch, R, Schulz, PE. Parkinsonism due to manganism in a welder. Int. J. Tox 2003; 22:393-401 William C. Koller, MD, Ph.D Kelly E. Lyons, Ph.D.