Acute Flaccid Paralysis (AFP)
Azad A Haleem
University of Duhok, College of Medicine
Heevi Pediatrics Teaching Hospital
• Definition of AFP
• Differential Diagnosis of AFP
• Protocol for AFP surveillance
• Certification (polio free)
• Clinical approach to children with AFP
• How to differentiate among
(Polio, Guillain-Barré syndrome, Traumatic
neuritis, Transverse Myelitis )
Definition of AFP
• sudden onset of weakness or paralysis in a
previously normal limb over a period of 15
days in a patient aged less than 15 years age.
• It is a Lower motor neurone lesion
• Surveillance is the collection, analysis,
interpretation and dissemination of
information about a selected health event.
• Health officials use the information to plan,
implement and evaluate health programs and
AFP surveillance in children
• To do this we have to
• report enough cases,
• send stools for enterovirus isolation using a
standardised protocol, and
• follow up children with AFP to determine the
AFP surveillance in children
• The non-polio AFP rate is an indicator of
• If it is < 1/100 000 CHILDREN below age 15 per
year then the surveillance system is probably
missing cases of AFP.
• Adequate stool specimens collected from
≥80% of AFP cases.
Protocol for AFP surveillance
Step Timing Description
Case Detection at diagnosis Follow case definition for AFP
Case Reporting ≤ 48 hours of report Tel:
Timing of stool
within 2 weeks of
onset of paralysis
2 stool specimens collected no less than
24 hours apart .
Fresh stool, or rectal swabs containing
fecal material (at least 8g – size of an
adult thumb). Place in a sterile glass
as soon as able.
laboratory ≤ 3 days
of being sent
Maintain a cold chain of 2 - 8 ⁰C.
Transport in dry ice if
transportation will take > 24 hours
Caution: avoid desiccation, leakage;
ensure adequate documentation
Follow up of
60 days from To determine whether there is residual
paralysis on follow up
Wild polio cases by country in the region for 2013-2014 (ending 06
Certification (polio free)
• Basic national documentation has been
accepted from countries that have been polio-
free for 3 years or more.
• Provisional national documentation for
regional certification has been accepted from
countries that have been polio-free for 5 years
or more and have completed phase I of
• Regular yearly updates (annual update and
abridged annual update) have been
submitted on a yearly basis
• by all countries whose basic national
documentation was accepted (annual update),
• and countries whose final national
documentation for regional certification was
accepted (abridged annual update).
• Annual updates have been received for years
2002–2006 and accepted.
• Final national documentation for regional
certification has been submitted, and was
accepted in 2008.
• Abridged annual updates and annual updates
have been received and accepted for years
How to differentionate among
• Guillain-Barré syndrome
• Traumatic neuritis
• Transverse Myelitis
24 to 48 hours onset
to full paralysis
From hours to ten
From hours to four
from hours to
High, always present
at onset of flaccid
paralysis, gone the
and after flaccid
and affecting only
Reduced or absent in
Reduced or absent
in affected limb
Decreased to absent Globally absent
Absent in lower
palms and soles
Pain in gluteus,
lower limbs with
Only when bulbar
affecting nerves VII,
IX, X, XI, XII
Only when bulbar
in severe cases,
normal or mild
Absent Transient Never Present
horn cell disease
(normal during the
first 2 weeks)
EMG Abnormal Normal Normal Normal
Sequel at three
months and up
atrophy of distal
only in affected
• It is an acute idiopathic acquired
inflammatory demyelinating polyneuropathy.
• GBS is the most common cause of acute
flaccid paralysis in healthy infants and
• It has an annual incidence of 0.6 to 2.4 cases
per 100,000 population and occurs at all ages
and in both sexes.
• Occurs rarely in children younger than two
years of age, but can occur in infants.
• Males are affected approximately 1.5 times
more often than females in all age groups.
• Immune mediated disease.
• There is no known genetic factors.
• Two third of cases follow a respiratory or GI infection.
• Campylobacter infection is the most common, but other
organisms include CMV, EBV, HSV, Enteroviruses,…
• Guillain-Barré syndrome has been reported to follow
– epidural anesthesia
– thrombolytic agents
Usually 2 - 4 weeks following respiratory or GI infection.
• The classic presentation:
Fine paresthesias in the toes and fingertips.
Lower extremity weakness: symmetric & ascending.
Inability to walk.
Respiratory muscles involvement.
• Cranial Neuropathy:
Facial nerve is most commonly affected, resulting in
bilateral facial weakness.
Miller Fisher syndrome: triad of external
ophthalmoplegia, Ataxia, areflexia with muscle weakness.
Clinical Features… cont
By the peak of the illness, the frequency of symptoms
was as follows:
- 79% had neuropathic pain
- 60% could not walk
- 51% had autonomic dysfunction
- 46% had cranial nerve involvement
- 24% could not use their arms
- 13% required mechanical ventilation
• Symmetric limb weakness
• diminished or absent reflexes
• Vibration and position sensation are affected in 40%
• Autonomic dysfunction:
Orthostatic hypotension, hypertension
• >90% of patients reach the nadir of their function within two
to four weeks, with return of function occurring slowly over
the course of weeks to months.
• The clinical course of GBS in children is shorter than in
adults and recovery is more complete.
• In patients who did not require mechanical ventilation, the
median time to recovery of independent walking was 43 to
52 days in children compared to 85 days in adults.
Forms of GBS
• Acute inflammatory demyelinating polyneuropathy
(AIDP): the most common form in developed countries.
• Acute motor axonal neuropathy: more common in
developing countries. More severe with common respiratory
involvement. Strong association with campylobacter
• Acute motor-sensory axonal neuropathy
• Polyneuritis cranialis: associated with CMV infection
- After the first week of symptoms typically reveals:
normal pressures, normal cell count and elevated
proteins (greater than 50 mg/dL)
- Early in the course (less than one week), protein levels
may not yet be elevated, but only rarely do they remain
- Most specific and sensitive tests for diagnosis
- Evidence evolving multifocal demyelination
- A normal study after several days of symptoms, makes
the diagnosis of Guillain-Barré syndrome unlikely.
• Critical care monitoring
autonomic and respiratory dysfunction.
• Children with the following should be admitted to PICU:
a. Flaccid quadriparesis
b. Rapidly progressive weakness
c. Reduced vital capacity (≤20 mL/kg)
d. Bulbar palsy
e. Autonomic cardiovascular instability
N.B: Sedation and neuromuscular blockade should be avoided
in ventilated patients because they obscure the course of the
Risk factors for respiratory failure in GBS:
Cranial nerve involvement.
Short time from preceding respiratory illness.
Rapid progression over less than 7 days.
Elevated CSF protein in the first week.
Severe weakness: unable to lift elbows above the bed
unable to lift head above the bed
unable to stand.
20% of children with GBS require mechanical
ventilation for respiratory failure.
Immune modulatory therapy:
• IVIG is preferred to plasma exchange in children because
of the relative safety and ease of administration, although
it has not been shown to have better results.
• Both therapies have been shown to shorten recovery time
by as much 50%.
• Combining plasma exchange and IVIG neither improved
outcomes nor shortened the duration of illness.
• IVIG and plasma exchange are not recommended for
ambulatory children with GBS who have mild disease or
for children whose symptoms have stabilized.
• Several IVIG regimens have been utilized. One regimen
includes daily IVIG for 5 days at a dose of 0.4 gm/kg/day,
which results in an improvement within a mean of 2 to 3 days
after the start of therapy. Other authors use 2 gm/kg of IVIG
given as a single dose or 1gm/kg/day for 2 days.
• One study compared the outcome of 0.4 gm/kg/day given for 3
days versus 6 days. In that study, the 6 days of IVIG was
superior when “time to walking” was used as an endpoint.
• When comparing treatments of 1gm/kg for 2 days versus
0.4gm/kg over 5 days, no significant difference in the
effectiveness was noted in the 2 treatment regimens. However,
early “relapses” were more frequently observed in the shorter
• Studies in children indicate that plasmapharesis may
decrease the severity and shorten the duration of GBS.
• It is most beneficial when started within 7 days of the
onset of symptoms but is still beneficial in patients
treated up to 30 days after disease onset.
• Corticosteroids are not effective and not indicated
• Interferon-ß reported to be beneficial in individual
cases, but its safety and efficacy have not been
established in clinical trials.
• In general, the prognosis in affected children is better
• Recurrences are uncommon but can occur in children.
Some may have a chronic progressive course, whereas
others may show recurrences or relapses.
• At long-term follow up, 93% were free of symptoms, and
the remainder were able to walk unaided.
• 50% are ambulatory by 6 mo, 70% walk within ayear of
onset of the disease.
• Mortality is approximately 3 to 4%, and usually is
secondary to autonomic dysfunction and respiratory
• polio= gray matter
• Myelitis= inflammation of the spinal cord.
• Poliomyelitis is caused by a virus that attacks
the nerve cells of the brain & spinal cord
although not all infections result in sever
injuries and paralysis.
• Caused by a poliovirus.
• 3 serotypes of poliovirus (genus Enterovirus).
• Type 1 most frequently associated with epidemics.
• Types 2 and 3 usually associated with vaccine-
associated paralytic polio (VAPP).
• In 1% of cases virus invades CNS.
• Multiplies and destroys anterior horn cells.
• In severe cases, poliovirus may attacks motor
neurones in brainstem, leading to difficulty in
swallowing, speaking and breathing.
• Incubation period of 7 to 14.
• Transmitted by oral-fecal contact.
• Person-to-person spread is the most common means of
transmission, followed by contaminated water.
• During epidemics, it also may be transmitted by
• Poliovirus initially infects the GI tract. It may spread to
lymph nodes and rarely to CNS.
• The mechanism of spread of poliovirus to the CNS is
not well understood.
• 3 months-16 years; rarely adults
• Predominant sex: Male = Female
• Improved sanitation led to many less infants being
exposed to poliovirus.
• When exposure occurred later and the individuals
were not protected by maternal antibodies, there
were polio epidemics.
Poliomyelitis: Incidence & Prevalence
Now rare; present in:
(a) Endemic settings.
(b) Small outbreaks in areas where polio eradication has
(c) Rarely as vaccine-associated paralytic polio (VAPP) cases.
• Endemic countries: Afghanistan, India, Nigeria and Pakistan
Poliomyelitis: Risk Factors
• Immune deficiency
• Poor sanitation and hygiene
• Unimmunized status, especially if <5 years
• Tonsillectomy: a risk factor for bulbar paralysis.
• Intramuscular injections or truama
• No genetic susceptibility has been identified.
• The majority of patients are asymptomatic.
• ~5% develop symptoms.
• ~10% will show signs and symptoms of a minor GI
illness, including fever, malaise, nausea, and vomiting.
• 0.1% develop the paralytic form of poliomyelitis.
• Symptoms of poliomyelitis always CNS specific.
Vary from one muscle or group of muscles, to
Proximal muscles: legs more commonly than arms.
Typically worsens over 2 to 3 days but sometimes can
progress for up to a week.
• Bulbar involvement:
5 – 35% producing dysphagia, dysarthria, and difficulty
• There may be encephalitis, usually in infancy.
• Cardiovascular & Resp. symptoms…bulbar poliomyelitis
• Significant motor loss on affected side or limb.
• Meningeal signs may be present in minor illness
or early phases of paralytic polio.
• Decreased deep tendon reflexes.
• Muscle atrophy of affected areas.
• Tone is reduced: asymmetric
• The sensory examination is normal.
• Based on the clinical presentation.
• Cerebrospinal Fluid:
Leukocytosis, Increased protein, Normal glucose.
• Virus recovery from stool, throat washing, blood.
Virus recovery from stool is essential to diagnosis.
Obtain stool, blood and throat samples for viral serology,
demonstrating a four fold rise in IgG is helpful but not
Positive IgM is diagnostic.
• Polymerase chain reaction amplification of poliovirus
RNA from CSF or serologically, by comparing viral titers
in acute and convalescent sera.
• Electrodiagnostic investigations reveal normal
sensory nerve studies.
• Motor nerve studies:
show normal to mildly slowed conduction
velocities and low to normal amplitudes.
• MRI may be helpful to evaluate involvement of
anterior horn of the spinal cord or other findings.
• No definitive treatment.
• Mainly supportive: pain relief and physical therapy
for muscle spasms.
• Patients with bulbar involvement require close
monitoring of cardiovascular status and autonomic
• Mechanical ventilation: Respiratory failure.
• Treatment of complications.
Clinical Course & Outcome
• About two-thirds of patients with acute flaccid paralysis
do not regain full strength.
• The more severe the acute weakness, the greater the
chance of residual deficits, Bulbar squeals are rare.
• The mortality was 5 to 10% in the era of epidemics, and
approached 50% for those with bulbar involvement
because of cardiovascular and respiratory complications.
• Jonas Salk created the inactivated poliovirus vaccine
(IPV), using killed virus in 1952.
• The Sabin oral poliovirus vaccine (OPV), using live
attenuated virus, proved successful in 1960.
• In areas of the world where polio is endemic, primary
immunization is still performed with Sabin OPV. But,
because it causes polio in one out of 2.5 million cases, it
has been replaced by the Salk IPV in countries without
polio, including the United States and most of Europe.
• Multiple doses required to achieve high humeral
conservation rates against all virus types
• Babies are given 4 doses through out their infancy.
• Adolescents and adults should get vaccinated as well.
• Adolescents younger than 18 should receive the routine
• You should get it if you travel outside places where polio
is still epidemic.
• Transverse myelitis is a condition
characterized by rapid development of both
motor and sensory deficits .
• Presumed autoimmune mediated
inflammation and demyelination of the spinal
• Postinfectious etiology largely predominates in
• An immunization history within the few weeks
preceding neurologic difficulties.
• Mean age of onset is 9 years.
• Symptoms progress rapidly, peaking within 2
• Usually level of myelitis is thoracic.
• Asymmetrical leg weakness, sensory level and
early bladder involvement.
• Recovery usually begins after a week of onset.
• Tenderness over the spine may point to trauma
• Increased tone, spastic weakness, legs more
• Reflexes are usually brisk, with positive
• Sensory ataxia, a sensory level.
• Sphincter dysfunction.
• Connective tissue diseases, e.g. SLE, JRA,
• Rarely seen in association with metabolic
causes of myelopathy such as vitamin B12
DIAGNOSTIC CRITERIA FOR
• Bilateral (not necessarily symmetric) sensorimotor and
autonomic spinal cord dysfunction
• Clearly defined sensory level.
• Progression to nadir of clinical deficits between 4 hours
and 21 days after symptom onset.
• Demonstration of spinal cord inflammation:
cerebrospinal fluid pleocytosis or elevated IgG index
or MRI revealing a gadolinium-enhancing cord lesion.
• Exclusion of compressive, postradiation, neoplastic,
and vascular causes.
• Symptomatic management of bowel and bladder
• Management of respiratory, cardiovascular &
• IV methylprednisolone .
• IV immunoglobulin (IVIG) or plasmapheresis.
• Cyclophosphamide has been reported to be
useful in myelitis associated with systemic
• Physical and occupational therapy may help
promote functional recovery and prevent
• 50% make a full recovery within 3 to 6
• 40% recover incompletely.
• 10% don’t recover.
• Older age, increased deep tendon reflexes, and
presence of Babinski sign may indicate better
• Rapid progression, back pain, and spinal shock
predict poor recovery.