This article requires a subscription to view the full text. If you have a subscription you may use the login form below to view the article. Access to this article can also be purchased.
Abstract
Background: Mutations in PARK8 (LRRK2) are associated with autosomal dominant parkinsonism and Parkinson disease (PD). Hyposmia is present in at least 80% of patients with PD and an accumulation of α-synuclein (α-syn) is seen in the olfactory pathways. In this study we have clinically examined olfaction and pathologically examined the rhinencephalon in individuals carrying the G2019S LRRK2 mutation.
Methods: The University of Pennsylvania Smell Test (UPSIT) was used to evaluate the sense of smell in 19 parkinsonian and two asymptomatic carriers of the G2019S mutation and compared with groups of patients with PD and healthy controls. Postmortem examination of α-syn accumulation in the rhinencephalon was also carried out in four parkinsonian carriers of the G2019S mutation.
Results: The mean UPSIT score in G2019S parkinsonian carriers was lower than that in healthy controls (p < 0.001) and similar to that found in patients with PD (p > 0.999). Smell tests in two asymptomatic carriers of the G2019S mutation were in the normal range. Postmortem studies of the olfactory pathways in one of the patients who had been clinically tested, and found to have hyposmia, and three other cases with the G2019S mutation, revealed α-syn deposition in the olfactory pathways in all cases.
Conclusions: Odor identification is diminished in LRRK2 G2019S mutation parkinsonism but the asymptomatic carriers of the mutation had normal olfaction. We found α-syn accumulation with Lewy bodies in the rhinencephalon in all four cases examined pathologically.
Glossary
- α-syn=
- α-synuclein;
- AOI=
- area of interest;
- CERAD=
- Consortium to Establish a Registry for Alzheimer’s Disease;
- LB=
- Lewy body;
- OT=
- olfactory tract;
- PD=
- Parkinson disease;
- QSBB=
- Queen Square Brain Bank for Neurological Disorders;
- UPSIT=
- University of Pennsylvania Smell Test.
AAN Members: Sign in with your AAN member credentials (e-mail or 6-digit Member ID number)
Non-AAN Member subscribers: Sign in with subscriber credentials
Log in using your username and password
Purchase access
Disputes & Debates: Rapid online correspondence
NOTE: All authors' disclosures must be entered and current in our database before comments can be posted. Enter and update disclosures at http://submit.neurology.org. Exception: replies to comments concerning an article you originally authored do not require updated disclosures.
- Stay timely. Submit only on articles published within the last 8 weeks.
- Do not be redundant. Read any comments already posted on the article prior to submission.
- 200 words maximum.
- 5 references maximum. Reference 1 must be the article on which you are commenting.
- 5 authors maximum. Exception: replies can include all original authors of the article.
- Submitted comments are subject to editing and editor review prior to posting.