[Challenges in the differential diagnoses of parkinsonism].

Parkinsonism (PD) is the clinical syndrome of bradykinesia combined with rigidity and/or tremor at rest. These are the defining characteristics of PD, but they are present in many other diseases of the brain. The most frequent differential diagnosis of PD are the atypical parkinsonian syndromes and the conditions presenting with mainly lower body parkinsonism. Discrimination between these can be challenging, especially at early stages of the disease, but nevertheless of utmost importance, because treatment and prognosis vary. Diagnoses are clinical, as disease-specific biomarkers are still lacking.