Nervous system Flashcards
Cerebral palsy definition
Epi
Non-progressive motor deficit: a chronic disorder of movement and/or posture that presents early (i.e. before 2y/o) and continues throughout life (note that CP is the disability, not the cause)
Severity of impairment increases with gestational age at birth. 2 in 1000 live births
Causes of CP
Choreoathatosis definition
Caused by: static injury to the developing brain (e.g. hypoxic ischaemia)
Assoc. with ↑risk of impairments including vision, hearing, speech, learning, epilepsy, nutrition, and psychiatric
Choreoathatosis: involuntary, irregular, unpredictable muscle movements which can affect the limbs, face, neck tongue and ither muscle groups
What are the risk factors for CP: categorise them into antenatal, perinatal and post natal:
Preterm birth (80%) (with ↑risk with ↓gestational age)
Congenital malformations
Multiple births: twins, triplets etc
Intrauterine infections – e.g. TORCH: toxoplasmosis, other viruses (HIV, measles etc), rubella, cytomegalovirus, herpes simplex
Chorioamnionitis
Toxic/teratogenic agents – e.g. maternal smoking, alcohol, cocaine
Maternal resp. tract/GU infection needing hospital Rx
Maternal illness – e.g. thyroid abnormalities/any condition leading to low birth weight
Perinatal factors (10%)
Low birth weight
Chorioamnionitis
Neonatal encephalopathy
Neonatal sepsis (esp. if birth weight <1.5kg)
Maternal resp. tract/GU infection needing hospital Rx
Postnatal factors (10%) Meningitis Intracranial haemorrhage Trauma Infection Hyperbilirubinaemia Hypoxia Seizures
Preventative measures for CP
Recognition and Rx of maternal iodine deficiency
Prevention of kernicterus (brain damage caused by hyperbilirubinaemia) assoc. with rhesus isoimmunisation
Rx to prolong pregnancy in preterm labour
Improved neonatal intensive care
Describe the 3 presentations of CP
Spastic
damage to which structure causes this?
General manifestations: abnormal tone in early infancy, delayed motor milestones, abnormal gait and feeding difficulties
Spastic CP: the commonest label – children can be hemiplegic (ipsilateral arm + leg), diplegic (both arms OR both legs), or quadriplegic
Spastic: Increased tone from damage to UMNs in the pyramidal tract
Hypertonia and hyperreflexia
General signs
Failure to meet milestones
Increased or decreased tone, generally or in specific limbs
Hand preference below 18 months is a key sign to remember for exams
Problems with coordination, speech or walking
Feeding or swallowing problems
Learning difficulties
Clasp knife phenomenon on rapidly stretching tendons, often described as a ‘catch’
Leg: ankle plantar flexion, and valgus/varus deformity of foot
Hip: flexion, limited adduction, and often internal rotation
Wrist: flexed and pronated
Elbow: flexed
Shoulder: adducted
Bulbar muscles may be spastic 🡪 dysphagia and driblling
Choreoasthetosis presentation (damage to which structure causes this?)
Ataxic CP presentation
(damage to which structure causes this?)
Choreoasthetosis/ dyskinetic (damage to basal ganglia and substantia nigra due to kernicterus)
As child matures, they often develop fixed reduction in joint range of movement (so signs become more difficult to distinguish from spastic CP)
Almost always have bulbar problems
Ataxic CP (= disequilibrium syndrome: due to cerebellar damage): extremely rare and poorly understood; aetiologically different from other types of CP (not due to hypoxia/ischaemia) Congenital ataxia 🡪 striking loss of balance in early years (= disequilibrium) Uncoordinated movements and intention tremor
Mobility milestones of CP
Complications of CP
The more severe the child’s physical, functional or cognitive impairment 🡪 the greater the possibility of difficulties with walking and speech/language, and of a ↓life expectancy
If a child can sit by age 2, they are likely (but not certain) to be able to walk unaided by age 6; if they can’t sit but can roll by 2, there is a possibility they may be able to walk unaided by 6; if they can’t sit OR roll by 2, they are unlikely to be able to walk unaided
Contractures
GI Sx and their sequelae – e.g. reflux, oropharyngeal muscle disorders, failure to thrive and osteoporosis
Pulmonary complications – e.g. aspiration pneumonia and bronchopulmonary dysplasia
Dental problems
Moderate/severe learning difficulties (in 30-50% of pts assoc. with severe spastic quadriplegia)
Hearing loss (esp. where the secondary cause is hyperbilirubinaemia/exposure to ototoxic drugs)
CP investigations
Important DDx
History is v. imp and can reveal cause of CP – e.g. prematurity/periods of hypoxic ischaemia (although child still needs a comprehensive assessment to exclude other disorders – esp. progressive ones)
Because the diagnosis is mainly clinical, it is important to observe the child on several occasions
Some authorities suggest deferring the diagnosis until the patient is 1-2 years old to exclude short-term conditions such as transient hypotonia
Imaging: MRI scan of the brain with reference to the pyramidal tracts in children with spasticity. If there is a problem identified in the history there should be signs of this on imaging
Differentials Acquired brain injury or tumour Familial/ primary dystonia Muscular dystrophy/ myopathy Myelodysplasia: immature blood cells do not become healthy adult cells Brain tumour Traumatic peripheral nerve lesions Becker's muscular dystrophy: gradually makes the body's muscles weaker and smaller
Management of CP
Multidisciplinary approach
Physiotherapy is used to stretch and strengthen muscles, maximise function and prevent muscle contractures.
Occupational therapy is used to help patients manage their everyday activities, such as getting dressed and using the bathroom. That can involve techniques to perform tasks despite disability. They can also make adaptations and supply equipment, such as rails for assistance or fitting a hoist for a patient who is entirely wheelchair bound.
Speech and language therapy can help with speech and swallowing. When swallowing difficultly prevents them meeting their nutritional requirements they may require an NG tube or PEG tube to be fitted.
Dieticians can help ensure they meet nutritional requirements. Some children may require PEG feeding through a port on their abdomen that gives direct access to the stomach.
Orthopaedic surgeons can perform procedures to release contractures or lengthen tendons (tenotomy).
Paediatricians will regularly see the child to optimise their medications. This may involve:
Muscle relaxants (e.g. baclofen) for muscle spasticity and contractures
Anti-epileptic drugs for seizures
Glycopyrronium bromide for excessive drooling
Social workers to help with benefits and support.
Charities and support groups provide opportunities to connect with others affected by cerebral palsy and learn and share information on the condition.
Red flag indicators for neurological disorders other than CP
Absence of known risk factors for cerebral palsy
Family history of a progressive neurological disorder
Loss of already attained cognitive or developmental abilities
Development of unexpected focal neurological signs
MRI findings suggestive of a progressive neurological disorder
MRI findings not in keeping with clinical signs of cerebral palsy
Consider repeating the MRI scan if there is a change in the expected clinical and developmental profile or if any red flags for a progressive neurological disorder appear
What do these gaits tell you about the location of the lesion
Hemiplegic/ diplegic gait Broad based gait/ ataxic gait High stepping gait Waddling gait Antalgic gait
Hemiplegic / diplegic gait: indicates an upper motor neurone lesion
Broad based gait / ataxic gait: indicates a cerebellar lesion
High stepping gait: indicates foot drop or a lower motor neurone lesion
Waddling gait: indicates pelvic muscle weakness due to myopathy
Antalgic gait (limp): indicates localised pain
Febrile fit definition and epi
Most common cause
Febrile seizures are short-lived tonic-clonic seizures that are precipitated by high fevers, most commonly associated with viral illnesses
They occur in up to 4% of all children, generally infants/small children between the ages of 6 months and 6 years
Most common cause is Roseola infantum
Differentiate between simple and complex febrile seizures
Causes of fever in children with febrile seizures
Simple febrile seizures (typical): generalised tonic-clonic activity lasting <15min with assoc. fever. Only occur once during a single febrile illness
Complex febrile seizures (atypical): these occur in up to 15% of cases, and are characterised by:
Focal seizure activity, OR
Prolonged seizure >15min, OR
Multiple seizures within a febrile illness
Difficult to rouse after
Older/younger children
(Not assoc. with high temperature) – but high fever doesn’t need to be at time of fit, can be after
Vast majority are: Viral infections Otitis media Tonsilitis Others: Gastroenteritis Post-immunisation
Febrile fit presentation
What factors increase the risk of further seizures ?
Most last a minute or two, but it can be just a few seconds. Others last for more than 15min
Typically, these children have no prior neurological disease or focal deficits on examination
May have a temperature >39°C, however the temperature may have become normal by the time it is measured
The seizure tends to occur during the first day of fever
Febrile seizures are lengthy, OR
Affect one part of the body,
Recur within 24h, OR
The child has neurological abnormalities
Febrile fit investigations
Important differentials
Blood tests: FBC, ESR, glucose, U&E, coagulation, culture
Urine microscopy/culture if: age <18 months, complex seizure or no focus of infection found
Lumbar puncture should be considered for:
Child<12 months – LP advised unless a paediatric registrar decides against LP and will review within two hours
A child 12-18 months – has a low threshold for LP
Epilepsy
Meningitis, encephalitis or another neurological infection such as cerebral malaria
Intracranial space occupying lesions, for example brain tumours or intracranial haemorrhage
Syncopal episode
Electrolyte abnormalities
Trauma (always think about non accidental injury)
Febrile fit urgent referral criteria
First febrile seizure
Serious illness not excluded
Previous Hx of febrile seizure with:
Child <18 months of age (meningitis is harder to detect in this age group)
Diagnostic uncertainty about the cause of the present seizure
A complex seizure (more likely to recur or be due to intracranial infection)
Antibiotics taken currently/recently (in case these mask signs of meningitis)
Early review by a doctor is not possible
Home circumstances are unsuitable
Also – consider referral if no focus of infection is found
Febrile fit management
Risk factors of developing epilepsy / further episode
Safety: remove danger, place child on side on protected surface, note the time
Assistance: call for help if unfamiliar then call ambulance
Treatment: If seizure lasts >5 mins treat them for status epilepticus. Once seizure has ended, child should be assessed for source of fever. Consider admission
Meningitis: Consider meningitis if stiff neck, extreme lethargy >4h post-seizure, abundant vomiting, or <12mnths old
If concern, perform lumbar puncture (as long as child is not encephalopathic)
Seizure prevention and home care: Parents should give standard antipyretics (paracetamol and ibuprofen) early and seek help soon as. Parents should call for help if seizure is lasting > 5 mins
RFs for developing epilepsy include a family history of epilepsy, having complex febrile seizures and a background of neurodevelopmental disorder
In children who get febrile seizures, the risk fo developing epilepsy in the future is 1-2%
Once a child has had one febrile convulsion, the risk of having a future febrile seizure is high- around 30-40%
What is roseola infantum the most common cause of?
What virus is responsible for roseola infantum ?
Roseola presentation
Management of Roseola?
Febrile seizures
Human herpes virus 6
Few days of fever followed by a widespread rose-pink macular rash with surrounding pale white halos. The fevers can be high (40 degrees)
Supportive
