Parkinsonism differ from atypical parkinsonism by the absence of
Resting tremor
Postural instability
Veical gaze palsy
Gait abnormality
Atypical Parkinsonisms Characterised by Progressive supranuclear palsy Coicobasal ganglionic degeneration Frontotemporal dementia Multiple-system atrophy a)Cerebellar type (MSA-c) b)Parkinson type (MSA-p) Poor response to dopamine early loss of balance prominent intellectual changes rapid onset of progression conspicuous postural hypotension urinary & bowel incontinence Little or no tremor Reference: Chapter 372. Parkinson's Disease and Other Movement Disorders Harrison's Principles of Internal Medicine 18th edition
All India exam