Diagnostic criteria for idiopathic Parkinson's disease.

Clinical diagnosis of parkinsonian syndrome is reasonably easy, but the dis tinction between idiopathic Parkinson's disease (IPD) and other parkinsonia n syndromes (Secundary parkinsonisms and "Parkinsons plus") may be vary dif ficult particularly in early cases. A correct diagnosis is not only importa nt for counselling and management of patients but also in conducting pharma cological and epidemiological studies. A critical analysis of the diagnosis criteria of IPD, based on the pathological verification, is discussed from recent data of literature. Without any validated and available criteria fr om functional imaging or molecular biology, the most effective diagnostic c riteria remain on the clinical range; the five most effective criteria are resting tremor, rigidity, bradykinesia, asymmetry at onset and marked levoD OPA responsiveness. The diagnosis of IPD should be periodically reassessed along the course of its natural history.