Tremor

Probability diagnosis

Benign essential (familial) tremor

Senility

Physiological

Drugs: adverse effects, withdrawal

Parkinson disease (incl. drug-induced PD)

Anxiety/emotional

Alcohol

Serious disorders not to be missed

Vascular:

• cerebral infarction → Parkinsonism

Infection:

• meningoencephalitis

• tertiary syphilis

Cancer/tumour:

• cerebral tumour (frontal lobe)

Other:

• toxicity from organ failure (kidney, liver, lungs)

Pitfalls (often missed)

Cerebellar disease

Multiple sclerosis

Alzheimer dementia

Uraemia of kidney failure

CO₂ retention of respiratory failure

Hepatic failure

Rarities:

• hepatolenticular degeneration (Wilson disease)

• lesion of midbrain (red nucleus)

Masquerades checklist

Drugs (withdrawal e.g. opioids, stimulants, illicit agents, benzodiazepines, caffeine, alcohol; adverse reactions e.g. sympathomimetics, ® agonists, lithium, phenothiazines, valproate, amiodarone; alcohol) Thyroid/other endocrine: (hyperthyroidism, hypoglycaemia, phaeochromocytoma)

Is the patient trying to tell me something?

Anxiety (esp. hyperventilation), conversion disorder (‘hysteria’).

Key history

• Nature of the tremor: resting, intention, postural (action), pill-rolling, flapping (asterixis), hysterical, mixed

• Family history of tremor

• Evidence of cognitive changes or other neurological problems

• Systems review: respiratory, cardiac, liver, kidneys

• Drug history: prescribed, OTC, illicit drugs, alcohol, caffeine

Key examination

• General appearance and vital signs

• Respiratory, cardiac, abdominal (esp. liver) and neurological examination

Key investigations

According to above:

• FBE and ESR

• thyroid function tests (?hyperthyroidism), LFTs, pulse oximetry/blood gases

• drug screen

• MRI.

Diagnostic tips

• Essential tremor eased by a small quantity of alcohol.

• Triad of essential tremor: postural or action tremor, head tremor, positive family history.

• Look for Parkinson tetrad: resting tremor, bradykinesia, rigidity, postural instability.

• Look for cerebellar tetrad: intention tremor, dysarthria, nystagmus, ataxic gait.

• Typical drugs that induce Parkinsonism are phenothiazine, butyrophenones, reserpine.