Poliomyelitis Ross Bills

Aetiology/Pathology  Acute infective disease with serious long term implications  Viral - enterovirus  Attacks anterior horn cells in grey matter spinal cord, motor nuclei brain stem  Three strains of virus, Types 1,2,3  Found in isolates from acute stage patients, convalescent patients and healthy subjects  Usual route of infection thought to be alimentary tract

Aetiology/Pathology  Acute Changes: general reaction in lymphoid tissue, congestion, oedema, “softening” of spinal cord  Histology: degeneration anterior horn cells spinal cord and medulla, inflammatory reaction with small haemorrhages in grey matter  During recovery ganglion cells that have not been too badly damaged may be restored to normal; others disappear completely  Paucity of cells in anterior horns, with secondary degeneration in anterior roots and peripheral nerves. Muscles supplied show signs of neural atrophy.

Epidemiology  Epidemic, sporadic  Immunisation has reduced cases  Healthy contacts may transmit infection  Global travel to non-immunised areas has seen a resurgence  In such areas where hygiene and/or sanitation is poor exposure is common in early childhood, resulting in infection or immunity  Incubation 7-14 days, up to five weeks  Precipitated by ENT surgery, dental work? (Provide a portal of entry?)

Symptoms  Four possible reactions:  Exposure may result in immunity  Symptoms of a mild general infection  In epidemics c. 75% of patients general symptoms, cells (inflammatory) in CSF, symptoms of meningitis but no paralysis (non-paralytic cases)  In a minority disease runs the the full course, and paralysis etc. ensues

Symptoms 2  Pre-paralytic Stage:  Headache, fever, malaise, drowsiness or insomnia, sweats, URTI symptoms, GIT upset 1-2 days, followed sometimes by improvement, or may progress to  More severe headache, back pain, limb pain, hyperaesthesia (in children neck stiffness, positive Kernig’s sign)  Recovery may ensue, or the patient may progress further to…

Symptoms 3  Paralytic Stage  Onset of paralysis, with fasciculations, limb pain, muscle tenderness, with widespread or localised paralysis, often asymmetrical and patchy  Maximal damage first 24 hours, but sometimes more slowly progressive  May spread from distal to central, and careful observation of the respiratory muscles is warranted  Brainstem damage may manifest with face, larynx, pharynx and tongue muscle damage, and occasionally the ocular muscles.  Respiratory embarrassment from saliva etc. may occur  Tremor and nystagmus may be found  Dysuria also may occur  Improvement may begin from the first week after onset of paralysis…

Symptoms 4  Recovery may occur from the first week after paralysis, and up to around three weeks.  From then those groups damaged will develop wasting, loss of reflexes, contractures due to opposition of stronger muscle groups, circulatory changes - blue, cold, oedema, vulnerability to injury (chillblains and such), retarding of bone growth

Symptoms 5  Good old lumbar puncture:  CSF from pre-paralytic stage onwards may show increased pressure, initially polymorphs and leucocytes, but after first week usually just lymphocytes, increased protein and globulin, normal Glucose and chloride

Diagnosis  Exclude other causes:  Impossible to diagnose clinically in the early “constitutional” stages of the illness  Early stages: meningitis, viral bacteria and tuberculous  In adults, Guillain Barre Syndrome, acute transverse myelitis  Cultures CSF including viral  Stools for polio virus

Prognosis  Mortality varies - up to 25%, highest in the very young  Cause of death: Bulbar and/or respiratory paralysis  Cessation of paralysis coincides with commencement of improvement, which may occur over the ensuing year.  Second attacks may occur (rare)

Treatment  Prevention  Immunisation of the young continues  Immunisation of older travellers to risk areas

Treatment  Specific treatment varies depending on the damage  Focusing on patient identified needs  Activity after the acute disease, including physiotherapy  Respiratory issues  Mobility  Care of limbs including prevention pressure sores, chilblains  Spasticity