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Monday, 14 August 2017

parkinsonism

PARKINSONISM


History of Parkinson´s disease (PD) :

First described in 1817 by an English physician, James Parkinson, in “An Essay on the Shaking Palsy.”
The famous French neurologist, Charcot, further described the syndrome in the late 1800s.

EPIDEMIOLOGY

ž  Incidence        =      0.2 / 1000
ž  Prevalence     =      1.5 / 1000
ž  The incidence and prevalence both increase with age.
ž  Sex incidence is slightly higher in men.

Typical Age of Onset

ž  Average age of onset is 60 yrs.
ž  5-10% of cases occur under the age of 40. Referred to as Young-Onset Parkinson Disease.
ž  Rarely seen under age 30.

Famous Faces of Parkinson  

Etiology

ž  Parkinson’s disease is referred to as idiopathic (unknown cause).

ž  Genetic link is seen in a small number of Parkinsons cases.
ž  Larger genetic link is found in young-

    onset Parkinsons disease

ž  MPTP(methyl phenyltetrahydropyridine)  cause severe parkinsonism in young drug users

Risk factor

  • ž Positive family history
  • ž  Male gender
  • ž  Head injury
  • ž  Exposure to pesticide
  • Factors which decrease incidence of PD
  • ž  Smoking
  • ž  Coffee drinking
  • ž  Use of NSAIDS
  • ž  Estrogen replacement in postmenopausal women 

Secondary Parkinsonism

ž  Repeated head trauma
ž  Infectious & post infectious disease
ž  Drugs (neuroleptics, antipsychotics , alpha methyldopa, lithium carbonate , fluoxetine )
ž  Toxins     MPTP
            Cyanides
            Methanol

Unilateral Parkinsonism

ž                  Vascular
                 Traumatic
ž                 Neoplasm

Lower body Parkinsonism

  • It may represent a form of vascular parkinsonism

Parkinsonism plus syndrome

ž  Features of parkinsonism associated with complex clinical presentation
ž  Failure to respond to treatment
ž  Worse prognosis
   Examples include :
                       1. Shy Dragger syndrome
                       2. Steel Richardson syndrome
                       3. Parkinsonism-dementia plus

PATHOLOGY

    There is depletion of pigmented dopaminergic neurons in the substantia nigra, atrophic changes in substantia nigra and depletion of neurons in locus coeruleus.

 
   Reduced dopaminergic output from the substantia nigra to globus pallidus leads to reduced inhibitory effect on subthalamic nucleus, neurons of which become more active in inhibiting activation of cortex resulting in bradykinesia.


CLINICAL FEATURES
ž  Four cardinal symptoms:
   T remor
®     R igidity
®     A kinesia
®     P osture and gait disturbance
               


General Features

  • ž    Expressionless face (mask like)
  • ž    Greasy skin
  • ž  Soft rapid indistinct speech, monotonous
  • ž  Glabellar tap sign
  • ž  Flexed posture
  • ž  Impaired postural reflexes

Gait
ž  Slow to start walking
ž  Shortened stride
ž  Rapid small steps
ž  Reduced arm swing
ž  Impaired balance on turning

ž  Glabellar tap sign

Tremors
ž  Resting                (4 - 6 Hz)
ž  Postural               (8-10 Hz)
Rigidity
  • ž    Cogwheel :

                   mostly in upper limbs
  • ž   Plastic / lead-pipe:

                  mostly in lower limbs
  • Bradykinesia
ž  Slowness in initiation or repeating movements
ž  Impaired fine movements

Investigations

ž  There is no specific medical test used to diagnose Parkinson disease.
ž  However, MRI and blood tests are used to rule out other possible conditions that have similar symptoms to Parkinson disease.

TREATMENT

  1. ž  Drug therapy
  2. ž  Surgical Treatment
  3. ž  Physiotherapy
  4. ž  Speech therapy

  • LEVODOPA
ž    It is the oldest and most effective treatment of PD.
ž   Brain enzymes modify the drug to create dopamine.
ž   It reduces slowness and stiffness of    muscles.
ž   Given in combination with peripheral decarboxylase inhibitors, carbidopa.
  • Anticholinergic agents
ž  Useful effects on tremors & rigidity but
   do not help bradykinesia.
ž    Adverse effects :
         Dry mouth , blurred vision , difficult               urination , constipation, confusion, 
         hallucinations
  
  • Amantadine
ž  Useful in controlling dyskinesia produced by dopaminergic treatment later in the disease.


  • Dopamine receptor agonists 
  • Bromocriptine, pergolide ,cabergoline , ropinirole

  • OTHER DRUGS
ž  COMT inhibitors:
   Catechol-O-methyl transferase inhibitors
ž  Selegeline

  • Surgical Options

ž     Surgical procedures are now available for specific patients who no longer respond to drug treatments.

PALLIDOTOMY

  It is a neurosurgical procedure that can reduce many of the symptoms of Parkinson Disease

General Treatment Strategies

ž  Help family/care partner, along with patient,  create ideas for adapting home environment to meet the patient’s needs.
  •   Modified kitchen
  •   Modified bathroom
  •   Full bathroom and bedroom on first floor
  •   Lift chair
  •     Remove rugs/carpet/furniture that could be easily tripped over

Social Participation

  • ž  Support groups
  • ž  Important to encourage continued involvement in activities important to their life.
  • ž  Participation in activities which are not physically taxing.
  • ž  Introduce techniques for enhancing voice volume.

Prognosis

  • ž    Depends upon the age of onset
  • ž    If symptom starting in middle life ,the disease is usually progressive & likely to shorten lifespan.
  • ž  n After 70 is unlikely to shorten life or become severe.

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