17 March 2010
Rajesh Pahwa, Kelly E. Lyons
Therapeutic
options for Parkinson's disease (PD) are currently limited to
symptomatic agents. Levodopa is the most efficacious treatment; however,
higher doses and long-term use are associated with adverse effects such
as motor fluctuations and dyskinesia. Early treatment of PD with other
agents such as dopamine agonists and monoamine oxidase type B inhibitors
can provide symptomatic benefit and delay initiation of levodopa
therapy.
Early treatment of PD is contingent upon early and accurate
diagnosis of the disease, which can be challenging because there are no
biomarkers or neuroimaging or other clinical tests available to confirm
the diagnosis. PD diagnosis is currently based on the presence or
absence of various clinical features and the experience of the treating
physician. A definitive diagnosis can be made only after autopsy.
Moreover, the signs and symptoms present in early PD can resemble those
of a number of other movement disorders, particularly other forms of
parkinsonism, such as multiple system atrophy, drug-induced
parkinsonism, and vascular parkinsonism, as well as diffuse Lewy body
disease and essential tremor.
Nevertheless, diagnosis of PD based on
clinical features and response to antiparkinsonian medication can be
achieved with a fairly high level of accuracy, particularly when made by
a physician specializing in movement disorders. This article reviews
and summarizes published recommendations for the clinical diagnosis of
PD.
