Aids to Diagnosis - Parkinson's
What is it?
Parkinson's disease is a degenerative neurological condition initially manifesting in deterioration in control of movement.
What causes it?
The exact cause is unknown. In it's early stage the predominant pathological manifestation is the loss of nigro-striatal dopaminergic cells. In later stages of disease the illness also features cortical and subcortical degenerative processes. In younger (under 50) patients we know that there can be a significant genetic component.
How does it present?
PD most commonly presents in the 50's and 60's in a number of ways. The patient or their relative may notice the tremor, they may notice difficulty in using their arm (for example in writing or counting change) or in walking (tripping on a pavement is common). they may also present with shoulder pain or depression.
How do you recognise it?
There are four cardinal features of Parkinson's disease. Two or more are needed to make the diagnosis.
1. Tremor: Typically at rest. Usually unilateral at first.
2. Bradykinesia: Slow movement and particularly initiation of movement.
3. Rigidity: An increase in tone, usually described as cog-wheel
4. Impaired postural reflexes. Failure of the reflexes that allow us to stand upright without falling.
How do you confirm it?
The diagnosis is made clinically. NICE recommends the opinion of a specialist within 6 weeks. The Brain Bank Criteria for the diagnosis of Parkinson's disease are sometimes used by specialists to confirm diagnosis.
Are any tests helpful before referral?
It is helpful to check thyroid function and vitamin B12, as well as to ensure that the patient is not taking medication likely to cause or exacerbate the symptoms (eg Prochlorperazine, Haloperidol)