Dr Orlapresentation8

Poliomyelitis and Post Polio Syndrome

Orla Hardiman

Beaumont Hospital

Dublin

Poliovirus

Poliomyelitis

• Disease of semi-developed societies

• Occurs in epidemics

• First described in Egypt, major cause of morbidity and mortality until 1960s

• Large epidemics in 1940s and 1950s in developed world, including Ireland

POLIOMYELITIS

• “Picornavirus”• 3 types: Poliovirus 1,2,3• Ingested, spread by

faeco-oral route: Commoner in areas of poor sanitation

• Infants protected by maternal antibodies

Poliomyelitis:Epidemiology

• “Silent circulation” Many hundreds may be infected prior to the development of a single case of paralysis

• WHO considers a single confirmed case of polio in an area of low occurrence an epidemic

Epidemiology of Polio in US

LIFE CYCLE OF POLIO VIRUS

Clinical Pattern of Polio

POLIO ATTACKS MOTOR NEURONES

Poliomyelitis:Clinical Features

• In 1% of cases virus invades CNS:

• Multiples and destroys anterior horn cells.

• In severe cases, poliovirus may attacks motor neurones in brainstem, leading to difficulty in swallowing, speaking and breathing

Poliomyelitis: Risk Factors

• Immune deficiency

• Pregnancy

• Removal of tonsils

• Intramuscular injections

• Strenuous exercise

• Injury

Measures to Prevent Infection

• Risk factor identification

• Quarantine

• Hygiene

• Vaccination: “Herd” immunity

• Eradication

Pointers for Parents: (USA 1951)

cleanpointers.gif

Poliomyelitis: Treatment

• No anti-viral agent has yet been developed

• “Treatment “ is symptomatic

• Supportive care in acute phase, including ventilation if necessary

• Negative pressure ventilators (“iron lung”) used in past

Poliomyelitis: Treatment

• Intensive physiotherapy

• (Sister Elizabeth Kenney’s method: Hot packs and passive stretching)

• Orthotics

Poliovirus: Eradication

• Limit infection and dissemination– Improve general hygiene: Clean water supply

• Polio Vaccines – Killed virus injected (Salk vaccine: 1955)– Live attenuated virus (Sabin vaccine 1961)

Inactivated Vaccine

• Immunity to Poliovirus 1,2,3

• Safe, effective

• Injection

• No gastrointestinal immunity: Risks of continued circulation of virus in endemic areas

• Expensive

Jonas Salk

Live Vaccine

– Live attenuated oral vaccine (Sabin, 1961):– Risks of viral mutation, leading to potential regain

of virulence: – Excretion of live virus thru’ faeces

– Live vaccine cheaper, and suitable for mass vaccination programmes

Poliomyelitis in USA Since Vaccinations

Poliomyelitis:Current Status

• Eradicated from developed world in 1960s

• Remains endemic in 7 countries

• Eradication plan by WHO by year 2000: not yet achieved, but progress is being made

• Methodology more difficult that for smallpox

Polio Eradication:Status in 1988

Polio Eradication: Status in 1998

Polio Revisited

• 5,000 (approx) survivors in Ireland

• Varying degrees of disability

• New health problems associated

with poliomyelitis infection

THE POST POLIO SYNDROME: EXPERIENCE FROM A TERTIARY NEUROLOGY REFERRAL

CENTRE IN IRELAND

Dr. Grainne Gorman,Catherine Lynch R.N.,Dr. Orla Hardiman

Department of Neurology, Beaumont Hospital.

Details Collated

• Age• Gender• Occupation• Age of onset,• symptoms at onset• weakness at onset• residual weakness• initial rehabilitation

• Use of callipers/ mobility aids at initial diagnosis

• Surgery• Current status • New onset of

symptoms • Concomitant disease

Results

• 9 Misdiagnoses– Transverse myelitis– Mononeuropathy– Cerebral palsy– Spina bifida– AVM55% affected before 5 years of age

• 77% cannot recall symptoms• 15% required respiratory support• 6 vaccine related.

3

11

20

30

14

9

4 4

2 21

0

5

10

15

20

25

30

Frequency

35-40 41-45 46-50 46-50 51-55 56-60 61-65 66-70 71-75 76-80 >80

Years

Age Distribution

New Symptoms

• limb weakness (n=38)• fatigue (n=40)• increased cold

sensitivity (n=4)• joint pain (n=48)• low back pain (n=27)• falls (n=26)

• reduced exercise tolerance (n=31)

• dysphagia (n=4)• respiratory symptoms

(n=5)• documented muscle

weakness and wasting with new disability (n=18).

New Onset of Symptoms

38

40

4

4827

28

18

31

26

4

5 LL weakness

Fatigue

Inc.cold sens

Jt pain

LBP

Mechanical

SMA

RET

Falls

Dysphagia

Respiratory

Natural History of Polio(Halstead)

Criteria For Diagnosis of Post Polio Syndrome

• A prior episode of paralytic

poliomyelitis

• EMG evidence of longstanding denervation

• A period of neurologic recovery and functional stability preceding the onset of new problems (Usually >20 years)

Criteria for Diagnosis of Post Polio Syndrome (cont’d)

• Gradual or abrupt onset of new non-disuse weakness in previously unaffected or affected muscles

• May be asssociated with fatigue, muscle pain, joint pain, decreased function, etc.

• Exclusion of other conditions that may cause the above features

Pathophysiology

Theories:• Remaining healthy

motor neurons can no longer maintain new sprouts

• Decompensation / chronic denervation and reinervation process.

• Denervation exceeds reinervation

Theories (contd.)

• Motor neuronal loss due to reactivation of a persistant latent virus.

• Infection of the polio survivor’s motor neuron by a different enterovirus

• Loss of strength associated with aging, in already weakened muscles

Possible Causes of Late Complications of Polio

Main Clinical Features of PPS

• Fatigue (Commonest)• Weakness• Muscle pain• Gait disturbance

• Respiratory problems• Swallowing problems• Cold intolerance• Sleep apnoea

Fatigue

• Prominent in the early hours of the afternoon• Decreases with rest• Pathogenesis:Chronic pain / Muscle pain• Sleep disorders/ respiratory dysfunction• Difficulty in remembering/ concentrating• Decreased muscular endurance / Increased

muscular fatigability• “Polio wall”• Generalized or muscular

Weakness

• Disuse

• Overuse

• Inappropriate use

• Chronic weakness

• Weight gain

• Joint problems

Muscle Pain

• Extremely prevalent in PPS

• Deep aching pain

• Myofascial pain syndrome / Fibromyalgia

• Small number of patients have muscle tenderness on palpation

Swallowing Problems

• Can occur in bulbar and non bulbar polio

• Subclinical asymmetrical weakness in the pharyngeal constrictor muscles : almost always present in PPMA (Post polio muscular atrophy)

• Not all are symptomatic

Cold Intolerance

Autonomic nervous system dysfunction?

May relate to sympathetic intermediolateral column damage during acute poliomyelitis

Peripheral component may include muscular atrophy leading to reduced heat production

Sleep Apnoea

• Combination of the following:• Central: residual dysfunction of surviving bulbar

reticular neurons• Obstructive: pharyngeal weakness and increased

musculoskeletal deformities from scoliosis or emphysema

• PPMA, diminished muscle strength of respiratory,intercostal & abdominal muscle groups

Risk Factors for Sleep Apnoea

• Age of onset (More severe disease in adolescents and adults)

• Severity of original paralysis

• Managed with BiPAP

Management of Post Polio Syndrome in Ireland

• Assessment

• Exclusion of other causes of disability

• Introduction to concept of interdisciplinary team

• Follow-up as necessary

Post Polio Syndrome Multidisciplinary Team

Neurologist

Rehabilitation physician

Rheumatologist

Respiratory physician

Voluntary organization

• Clinical Professional Services: – Physiotherapy

– Occupational Therapy

– Speech and Language Therapy

– Social Services

Management of Post Polio Syndrome in Ireland

• Evaluation:– Neurologic Examination to define nature of

new weakness (neurogenic v disuse)– Neurophysiology– Pulmonary Function studies, polysomnography

if necessary– Rheumatology /rehabilitation assessment– Swallowing study: Aspiration risk

Management of Post Polio Syndrome in Ireland

• Radiography– Chest (aspiration,

Diaphragmatic paresis)

– Joints (arthritis)

Management of Post Polio Syndrome in Ireland

• Specialised Orthotics

• Community-based Services

• Access to free medical care and disability-based tax exemptions

Measuring Progression

• 6 monthly quantitative muscle assessment

• Measurement of strength in individual muscles

• Identification of rate of progression in PPMA

SERIAL QMAs IN 16 MUSCLES

Normal Values 65-70 (kgs)Percentiles

Oct-00 Apr-02 Apr-04 12-May-05 MEDIAN 10th 5thTESTNeck Flexion 6.1 7.3 NT NT 7.8 5.8 4.6Shld Add L 13.5 8.4 8.6 8.9 13.2 9.4 7.4Shld Add R 12.9 8.9 6.6 6.4 14.4 9.6 7.7Elb Ext L 7.3 8.4 8.5 6.1 8.6 5.7 5.1Elb Ext R 8.8 7 7.6 8.3 9.4 6.4 5.6Shld Abd L 4.2 4.1 3.4 3 5.6 2.6 2.2Shld Abd R 5.2 3.4 2.4 2.2 6.8 3.2 2.5Elb Flex L 11.8 10.2 8 9 14.5 10.9 9.3Elb Flex R 14.2 9.3 7.3 7.5 15.1 10.9 10.2Hand Grip L 13.4 16.7 18.3 16.9 18.9 14.8 13Hand Grip R 17.4 16.1 20.6 15.9 20.1 15 13.5

Hip Flex L 8.1 6.9 NT 7.3 14.7 10.7 9.6Hip Flex R 13.5 9.2 8.3 8.6 15.4 11.8 10.9Ankle DF L 4 4.4 6 6.4 16.6 11.7 10.6Ankle DF R 6.4 5.3 5.9 6.2 17.3 12.7 11.9Knee Ext L NT NT NT NT 19.7 13.4 11.2Knee Ext R 2.7 2.6 2.1 2 21.8 15 12.4Knee Flex L NT NT NT NT 10.2 5.6 5.2Knee Flex R 4.1 4.4 3.5 5.1 11.4 6.1 5.6

KGS

CHANGES IN STRENGTH OVER TIME USING QMA

0

5

10

15

20

25

2000 2001 2002 2003 2004 2005

Test Dates

Kilo

gram

mes

Shld Add R

Elb Ext R

Shld Abd R

Elb Flex R

Hand Grip R

02468

10121416

2000 2001 2002 2003 2004 2005

Time

Kilog

ramme

s

Hip Flex R

Ankle DF R

Knee Ext R

Knee Flex R

Research

• Maximum Voluntary Isometric Contraction: Serial testing at 6 month intervals

• Detailed electromyography

• Fatigue measurement & correlation with muscle strength

• Tests for Diabetes Mellitus

ELECTROMYOGRAPHY

• Abnormal in all people who had polio

• Distinctive pattern in people with PPS

Treatment /Management

• Recognition• Symptomatic and supportive

– Occupational therapy: orthotics etc

• Fatigue /sleepiness– Look for features of sleep apnoea– energy conservation

CONCLUSIONS

• Polio may have been over diagnosed in the past

• PPS is under-recognised

• Specialist clinic is beneficial

• Management is multidisciplinary

• Many research questions remain