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e u r o p e a n j o u r n a l o f p a e d i a t r i c n e u r o l o g y 1 5 ( 2 0 1 1 ) 3 9 0e4 0 4
Official Journal of the European Paediatric Neurology Society
Invited papers presented at the EPNS 2011 Cavtat meeting
Movement disorder emergencies in childhood
F.J. Kirkhama,b,c,*, P. Haywood a,d, P. Kashyape a, J. Borbone a, A. Lording a, K. Pryde a,M. Cox a, J. Keslake a, M. Smith a,d, L. Cuthbertson a, V. Murugan a, S. Mackie a,N.H. Thomas a, A. Whitney a, K.M. Forrest a, A. Parker e, R. Forsyth f, C.M. Kipps a
aSouthampton University Hospitals NHS Trust, UKbClinical Neurosciences, University of Southampton, UKcUCL Institute of Child Health, London, UKdCommunity Child Health, Southampton, UKeAddenbrooke’s hospital, Cambridge, UKf Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, UK
a r t i c l e i n f o
Article history:
Received 3 April 2011
Accepted 17 April 2011
Keywords:
Chorea
Dystonia
Status dystonicus
Paroxysmal Autonomic Instability
with Dystonia
Sandifer syndrome
Myoclonus
Opsoclonus
Tremor
Parkinsonism
Drugs
Neuroleptic malignant syndrome
Metabolic
Infection
Sydenham’s chorea
Systemic lupus erythematosus
Cardiopulmonary bypass
Wilson’s disease
Organic aciduria
Biotin
Creatine
* Corresponding author. UCL Institute of ChiE-mail address: fk@soton.ac.uk (F.J. Kirkh
1090-3798/$ e see front matter ª 2011 Europdoi:10.1016/j.ejpn.2011.04.005
a b s t r a c t
The literature on paediatric acute-onset movement disorders is scattered. In a prospective
cohort of 52 children (21 male; age range 2mo-15y), the commonest were chorea, dystonia,
tremor, myoclonus, and Parkinsonism in descending order of frequency. In this series of
mainly previously well children with cryptogenic acute movement disorders, three groups
were recognised: (1) Psychogenic disorders (n ¼ 12), typically >10 years of age, more likely
to be female and to have tremor andmyoclonus (2) Inflammatory or autoimmune disorders
(n ¼ 22), including N-methyl-D-aspartate receptor encephalitis, opsoclonus-myoclonus,
Sydenham chorea, systemic lupus erythematosus, acute necrotizing encephalopathy
(which may be autosomal dominant), and other encephalitides and (3) Non-inflammatory
disorders (n ¼ 18), including drug-induced movement disorder, post-pump chorea, meta-
bolic, e.g. glutaric aciduria, and vascular disease, e.g. moyamoya. Other important non-
inflammatory movement disorders, typically seen in symptomatic children with under-
lying aetiologies such as trauma, severe cerebral palsy, epileptic encephalopathy, Down
syndrome and Rett syndrome, include dystonic posturing secondary to gastro-oesophageal
reflux (Sandifer syndrome) and Paroxysmal Autonomic Instability with Dystonia (PAID) or
autonomic ‘storming’. Status dystonicus may present in children with known extrapyra-
midal disorders, such as cerebral palsy or during changes in management e.g. introduction
or withdrawal of neuroleptic drugs or failure of intrathecal baclofen infusion; the main risk
in terms of mortality is renal failure from rhabdomyolysis. Although the evidence base is
weak, as many of the inflammatory/autoimmune conditions are treatable with steroids,
immunoglobulin, plasmapheresis, or cyclophosphamide, it is important to make an early
diagnosis where possible. Outcome in survivors is variable. Using illustrative case histories,
this review draws attention to the practical difficulties in diagnosis and management of
this important group of patients.
ª 2011 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights
reserved.
ld Health, London, UK.am).ean Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved.
e u r o p e a n j o u r n a l o f p a e d i a t r i c n e u r o l o g y 1 5 ( 2 0 1 1 ) 3 9 0e4 0 4 391
Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3912. Dystonia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 392
2.1. Syndromes in patients with previously diagnosed dystonia (symptomatic) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3922.1.1. Status dystonicus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3922.1.2. Paroxysmal Autonomic Instability with Dystonia (PAID) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3952.1.3. Sandifer syndrome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3962.1.4. Rett syndrome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 396
2.2. Cryptogenic acute dystonic syndromes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3962.2.1. Infections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3962.2.2. Metabolic conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3962.2.2.1. Leigh syndrome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3962.2.2.2. Organic acidaemias . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 396
3. Chorea . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3973.1. Symptomatic chorea . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 397
3.1.1. Post-cardiopulmonary bypass chorea . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3973.1.2. Herpes simplex encephalitis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 398
3.2. Cryptogenic chorea . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3983.2.1. Sydenham’s chorea . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3983.2.2. Systemic lupus erythematosus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3983.2.3. Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 399
4. Myoclonus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3994.1. Opsoclonus-myoclonus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 399
5. Parkinsonism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4006. Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 400
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 400
1. Introduction with the multidisciplinary team. Rehabilitation and psycho-
The literature on recognition andmanagement of acute-onset
movement disorders in adult practice is scattered1 and is
very limited for paediatric practice, except for reviews on
drug-induced neuroleptic malignant syndrome which typi-
cally has clinical features of paroxysmal autonomic instability
with dystonia (PAID), and may evolve into life-threatening
status dystonicus.2,3 Some paediatric cases within the spec-
trum of status dystonicus/PAID but unrelated to drug treat-
ment have been published under the term ‘neuroleptic
malignant syndrome’. Chorea, dystonia, tremor, myoclonus,
and Parkinsonism can all present acutely, and since somemay
be treatable, timely recognition and diagnosis is important to
prevent morbidity.
Disorders with a psychological component are relatively
rare in paediatric movement disorder clinics, but are common
acute presentations in practice.4 Patients are more likely to be
female, particularly if >13 years of age, and to have tremor,
dystonia or myoclonus, often after a triggering traumatic or
infectious illness.4,5 Rehabilitation by experienced physio-
therapists and occupational therapists is usually successful
provided that the adolescent and family engage with
psychological input in addition and the search for organic
pathology ceases. It is important to remember this from
a practical point of view despite the increasing evidence for
overlap with organic disorders.6 It is not harmful (and may
even be helpful) to consider low risk treatment strategies such
as antibiotics,7 provided that the family continues to engage
logical support are also important for children where there is
convincing evidence for an organic pathology.
In a prospective4 cohort of 52 children (21 male; age range
2mo-15y), the commonest movement disorders were chorea,
dystonia, tremor, myoclonus, and parkinsonism (Table 1) in
descending order of frequency. In this series of mainly
previously well children with cryptogenic acute movement
disorders, three groups were recognised:
(1) Psychogenic disorders (n ¼ 12)
(2) Inflammatory or autoimmune disorders (n ¼ 22), including
N-methyl-D-aspartate receptor encephalitis (Fig. 1A),
Sydenham chorea and other post-streptococcal movement
disorders (Figs. 1B, 1C1e3) opsoclonus-myoclonus (which
may be paraneoplastic in relation to Neuroblastoma, Fig.
1D), systemic lupus erythematosus, acute necrotizing
encephalopathy (which may be autosomal dominant),
and other encephalitides (Table 2) and
(3) Non-inflammatory disorders (n ¼ 18), including drug-
induced movement disorder, post-pump chorea and
Tourette syndrome (Fig. 1E), metabolic, e.g. Leigh’s disease
(Fig. 1F) glutaric aciduria,8 and vascular disease, e.g.
moyamoya (Fig. 1G).9,10 Other important non-
inflammatory movement disorders, typically seen in
symptomatic children with underlying aetiologies such as
trauma, severe cerebral palsy11, epileptic encephalopathy,
post-hemispherectomy, after shunt dysfunction in
hydrocephalus,12 Down syndrome and Rett syndrome
Table 1 e Acute movement disorders in children: emergency investigation and management.
Movement disorder Definition Essential investigations Treatments to consider
Chorea brief, abrupt, irregular, unpredictable,
non-stereotyped movements
ASO titre
Anti-DNase B
Anticardiolipin antibodies
Lupus anticoagulant
Antibodies against NMDAR in
serum/CSF
MRI/MRA
Antibiotics
Steroids
Immunoglobulin
Plasma exchange
Cyclophosphamide
Dystonia abnormal, involuntary muscle
movements due to sustained muscle
contractions resulting in twisting
and/or repetitive,
patterned movements
Creatine kinase
Urine myoglobin
Urea, creatinine
Lactate in plasma/CSF
Antibodies against NMDAR in
serum/CSF, ASOT, Anti-DNAase B
Serum copper and caeruloplasmin
Organic acids
Mutation Ran-BP & RYR
MRI/MRA
Benzodiazepines
Morphine, Bromocriptine
Beta-blockers, Clonidine
Rx Gastro-oesophageal
reflux & constipation
Botulinum toxin
Baclofen, Anticholinergics
Trihexyphenidyl
Intrathecal Baclofen
Deep brain stimulation
Pallidothalamotomy
Myoclonus sudden, fast, arrhythmic movement
(electric shock-like), generally repeated
in the same part of the body
Urine VMA
Tumour imaging Steroids
Cyclophosphamide
Benzodiazepines
Tremor unintentional, rhythmic, oscillation
of a body part in a fixed plane
Serum copper and caeruloplasmin
Parkinsonism bradykinesia
rigidity
Calcium, magnesium,
carboxyhaemoglobin,
ASO titre, Anti-DNAase B
Antibiotics, Antivirals
Benzodiazepines
L-Dopa, Amantadine
e u r o p e a n j o u r n a l o f p a e d i a t r i c n e u r o l o g y 1 5 ( 2 0 1 1 ) 3 9 0e4 0 4392
include dystonic posturing secondary to gastro-
oesophageal reflux (Sandifer syndrome) and/or con-
stipation as well as PAID or autonomic ‘storming’. Status
dystonicus, whether seen in a child with dystonic cerebral
palsy and an intercurrent infection, drug-induced (neuro-
leptic malignant syndrome) or secondary to withdrawal/
failure of intrathecal baclofen infusion, is a life-
threatening medical emergency because of the risk of
rhabdomyolysis. Some paediatric cases within the spec-
trum of PAID/status dystonicus have been reported as
‘neuroleptic malignant syndrome’ even when drugs were
unlikely to have played a role12 and there is also clinical
overlap with the syndrome of malignant hyperpyrexia.
This review draws attention to the practical difficulties in
diagnosis and management of this important group of
patients with illustrative case histories.
2. Dystonia
2.1. Syndromes in patients with previously diagnoseddystonia (symptomatic)
2.1.1. Status dystonicusThis emergency typically occurs in children already known to
have a dystonic movement disorder such as cerebral palsy,11
acquired brain injury, Wilson’s disease,11 Huntingdon
disease, neurodegeneration with brain iron accumulation e.g.
Pantothenate Kinase-Associated Neurodegeneration (Fig.
1H),13 and severe epilepsies such as infantile spasms
secondary to the ARX mutation epilepsy.14 Triggers include
infection and drugs such as clonezepam, Penicillamine,
Haloperidol, Clozapine, Risperidone, Metachlorpropamide
and Ondansetron or drug withdrawl.15 Increasing muscle
contractions lead to rhabdomyolysis with acute renal failure
secondary to myoglobinuria, which is life-threatening and
should be excluded with regular creatine kinase and urinary
myoglobinmeasurements. Admission to the high dependency
or intensive care unit is important and many patients require
ventilation as well as dialysis if indicated for the renal failure.
Positioning, ideally with trunkal flexion, and treatment of
gastro-oesophageal reflux and constipation are important.
Midazolam may reduce the frequency of muscle contraction
sufficiently to avoid rhabdomyolysis in patients with treatable
dystonias, such as Wilson’s disease, or in those with cerebral
palsy in whom status dystonicus has been precipitated by
infection. The patient can then be gradually weaned from
sedation and ventilation although agitation and tremor may
be a problem for several days. Themortality has beenhigh and
it may be difficult to determine whether death is secondary to
the triggering sepsis, the use of drugs such as Propofol or the
status dystonicus (case 1). Status dystonicus in progressive
dystonias, e.g. Neurodegeneration with brain iron accumula-
tion (Fig. 1H), may require more aggressive management e.g.
intrathecal baclofen infusion,12,15,16 bilateral pallidal deep
brain stimulation12,17,18or pallidothalamotomy.13
Case 1. A girlwith severedystonia secondary to birthasphyxia
had had a fundoplication for severe gastro-oesophageal reflux
at the age of 2 years which had been associated with
Table 2 e Cryptogenic acute movement disorders in children: diagnosis and early management.
Primarymovementdisorder
Aetiology Movements Diagnosis MRI Management
Chorea Sydenham chorea Chorea, Dystonia, motor tics, dystonia,
tremor, stereotypies, opsoclonus,
myoclonus
ASOT, anti-
streptolysin B
May show unilateral
or bilateral basal ganglia
& white matter abnormality
Penicillin. More severe
cases may benefit from
steroids. Sodium valproate
or Carbamezepine
Systemic lupus
erythematosus
Chorea lupus anticoagulant,
anti-nuclear antibody,
anti-double-stranded
DNA antibody
Anticoagulation,
immunosuppression
N-methyl-D
-aspartate receptor
encephalitis
Chorea, Dystonia,
Parkinsonism
antibodies against
NMDAR in serum/CSF
May have lesions in
white matter & pons
Steroids, plasma exchange,
cyclophosphamide
Acute necrotizing
encephalopathy
Chorea, Dystonia,
Parkinsonism
Clotting and liver
dysfunction
Swelling & enhancement
thalami, posterior putaminae,
brainstem, cerebellar white
matter
Steroids
Moyamoya Chorea MRA Focal ischaemia Revascularisation
Focal cerebral
arteriopathy
Chorea, dystonia MRA Focal ischaemia Aspirin
Dystonia Mycoplasma
encephalitis
Dystonia, Parkinsonism Thalamic necrosis,
striatal necrosis
Erythromicin, steroids
Glut-1 deficiency Episodic dystonia Low CSF: plasma
glucose; SLC2A1 gene
Ketogenic diet
Biotin dependant
basal ganglia
disease
SLC19A3 gene, Trial
of biotin
Bilateral central
necrosiscaudate
head, involvement putamen
Biotin
Creatine deficiency
syndromes
Plasma creatine, creatinine,
Urine Guanidinoacetate
Proton MRS: absence
of creatine/
phosphocreatine
peak basal ganglia
Oral creatine
supplementation
Dihydrolipoamide
acetyltransferase
deficiency
Episodic dystonia E2 pyruvate dehydrogenase Ketogenic diet
Glutaric aciduria type 1 Dystonia urine organic acids Basal ganglia DWI
abnormality, subdurals,
Low lysine diet,
carnitine supplements
Rapid onset dystoniae
parkinsonism
Dystonia, Parkinsonism ATP1A3 gene
Leigh’s disease Dystonia, hypotonia Mitochondrial DNA,
SURF-1, pyruvate
dehydrogenase, muscle
biopsy for complex I-V
enzymes
brainstem & basal ganglia
(putamen) T2-W abnormality
Avoid hypocapnia
Pantothenate kinasee
neurodegeneration
Dystonia,
Parkinsonism
‘eye of the tiger’ sign Deep brain stimulation
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Table 2 (continued )
Primarymovementdisorder
Aetiology Movements Diagnosis MRI Management
Phospholipase A2 group
6-associated
neurodegeneration
Dystonia,
Parkinsonism
Acanthocytosis;
ERG: retinopathy;
PANK2 gene
Cerebellar atrophy,
hypointensity globus
pallidus, substantia
nigra, subthalamic
Deep brain stimulation?
EEG: high amplitude
fast; EMG: denervation;
Nerve conduction:
axonal sensory
neuropathy; PLAN gene
Myoclonus Opsoclonusemyoclonus
syndrome
Clinical, Urinary VMA,
exclude coeliac
Tumour imaging Steroids,
cyclophosphamide,
Rituximab
Parkinsonism
/rigidity
Hypocalcaemia Low calcium Calcium
Hypomagnesaemia Low magnesium Magnesium
Carbon monoxide Carboxyhaemoglobin White matter
abnormality
Hyperbaric
oxygenation
Acute disseminated
Encephalomyelitis
White matter
abnormality
Methyl
prednisolone
Encephalitis lethargica Sleep disturbance
dyskinesia,
ophthalmoplegia.
Grey matter
abnormality
in 40%
Methyl
prednisolone
Malignant Hyperthermia Gene encoding
for ryanodine
receptor (RYR1) on
chromosome 19q13.1.
Dantrolene
Tetanus Muscle spasms
triggered by stimuli,
autonomic
Instability, trismus,
spasms in limb
History, anti-tetanus
antibody excludes
Tetanus immune
globulin, antibiotics.
Benzodiazepines,
phenobarbitone
and avoidance
excessive sensory
stimulation
baclofen
Rabies High fever, agitation,
hallucinations,
violent behaviour,
autonomic
instability, hydrophobia.
Saliva sample, hair
follicle or nape-of-neck
biopsy for antigen
Prolonged
intensive care
Neuroleptic malignant
syndrome
Drug history Stop drugs, sedation,
intensive
care, dialysis
Hyperekplexia Exaggerated startle Glycine receptor
(GLRA1) gene
Benzodiazepines
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improvement in themovement disorder sufficient to allowher
to be appropriately seated. At the age of 10 years, she had
a febrile illness associated with marked deterioration in the
dystonia. On admission her creatine kinase was significantly
elevated at 15,450 IU/L and she was in renal failure, passing
only small amounts of rusty-coloured urine consistent with
myoglobinuria. Despite ventilation, dialysis and a midazolam
infusion, she died within 24 h of admission.
2.1.2. Paroxysmal Autonomic Instability with Dystonia(PAID)Dystonias are very common in patients with acquired brain
injury (ABI).11,12,19 The term Paroxysmal Autonomic Instability
with Dystonia (PAID) or paroxysmal sympathetic storms20e23
has been suggested to describe a syndrome of intermittent
agitation, diaphoresis, hyperthermia, hypertension, tachy-
cardia and tachypnoea. PAID is commoner in younger
patients24 and is becoming a better recognised phenomenon
in children with congenital syndromes, e.g. Rett25e27 and
Down28e30 (cases 2 and 3) as well as those with ABI20,31,32 who
have prolonged episodes of autonomic instability (case 4).
Children who have neuroleptic malignant syndrome3 on
exposure to drugs such as clozapine, risperidone, metoclo-
pramide hydrochloride and haloperidol have similar features
as well as hyperpyrexia and status dystonicus.
Patients should be adequately hydrated, alternative diag-
noses, e.g. epilepsy and gastrointestinal disorders such as
reflux oesophagitis and constipation, should be excluded and
any triggers, e.g. pain, and drugs should be avoided or actively
managed. The episodes may respond to morphine33 or
nonselective beta-blockers e.g. propranolol.34 Bromocriptine
mesylate has been used successfully in adults33,35,36 and
anticholinergics and gabapentin may have a role.2,37,38 Dan-
trolene sodium has been used in adults with hyperpyrexia but
did not decrease the duration of symptoms in children with
neuroleptic malignant syndrome.3 Although escalation may
be too slow for the acute situation, Trihexiphenydyl can be
tried, starting at a dose of 0.5mg daily in children<7 years or 2
mg daily in children>7 years, increasing by 0.5e2mg every 10
days until an effect or the maximum dose is reached (for an
infant 3 mg tds; for a child 1.5e10 years of age, 10 mg tds and
for a child>10y, 25 mg tds. In our experience, clonidine (orally
test dose 1 mg/kg observing for hypotension, increasing by 1e3
mg/kg/dose to a maximum of 5 mg/kg three times daily; intra-
venous infusion on PICU only 0.25 mg/kg/hour increasing until
sedation achieved to maximum 2 mg/kg/min) is helpful in
some patients with severe PAID in the context of ABI.32 Six
cases (all boys) with ABI sustained at a median of 12.5 (range
0.8e14) years were seen over 2 years. Three had suffered
hypoxic-ischaemic insults (after drowning, pneumococcal
meningitis and sepsis). The other three had septic shock, post
radiotherapy stroke and traumatic brain injury. Neuroimaging
showed global brain ischaemia in one, borderzone ischaemia
in 2, diffuse axonal injury in one,multiple brain infarcts in one
and left basal ganglia infarct with bilateral motor cortex
hyper-intensity in one. All patients had bilateral brain damage
and all remained unconscious when they developed PAID at
a median of 17.5 (range 7e42) days after ABI. Clonidine was
given to a maximum dose of 160 mg/kg/day for a median of 21
(10e90) days and was then weaned over a median of 25
(14e440) days. Five also received benzodiazepines and one
also received Baclofen and Morphine. Four patients had no
PAID at discharge but symptoms remained a problem in two
patients, needing ongoing treatment with Clonidine.
Successful outcome in treating PAID in traumatic brain injury
in these cases suggest that high dose clonidine should be
considered for treating PAID episodes. Intrathecal baclofen
may be effective in refractory cases and Dantrolene and
electroconvulsive therapy have occasionally been used in
children with neuroleptic malignant syndrome, although
there is scanty evidence for a reduction in the duration of
symptoms.2,3
Case 2. A 12 year old girl with classical Rett Syndrome had
a two year history of screaming episodes. Previously, her
seizures were well-controlled with lamotrigine. Aged ten, she
developed prolonged episodes of screaming and posturing.
These episodes persisteddespitenumerous investigations and
interventions, including dental extraction, multiple anticon-
vulsants and optimal treatment of gastro-oesophageal reflux
and constipation. The possibility of PAID was considered and
a trial of labetolol produced remittance of the episodes.
Case 3. A three year old boy with Trisomy 21 was admitted for
management of a reported increase in seizure activity. At
sixteen months of age, his parents reported abnormal move-
ments suggestive of infantile spasms. In retrospect, these
appeared to have started at around 4 months of age. Develop-
ment was static and EEG showed hypsarrhythmia. West
Syndrome was diagnosed and treated aggressively with pred-
nisolone, rapidly rendering him seizure-free. His develop-
mental progress then improved. He remained seizure-free until
aged three when he presented with a two-week history of pro-
longed episodes of stiffening, arching and laboured breathing.
High-dose prednisolone had been commenced with no effect.
Observation of the episodes revealed dystonic posturing,
tachypnoea, upper airway noise, increased work of breathing
and sweating. EEG during the episodes showed no epileptiform
activity. PAID was suspected and propranolol and clonazepam
were commenced with significant reduction in the frequency
of episodes. Two months later clonidine was added for
breakthrough episodes, with a good therapeutic response.
Case 4. A 2 year old boy suffered a near drowning accident
when he was found face down in a swimming pool. MRI of the
head showed extensive bilateral, predominantly posterior,
abnormality in both cerebral hemispheres with involvement
of the cortico-spinal tracts bilaterally, the posterior brainstem
and cerebellum, representing extensive hypoxic-ischaemic
injury. He developed a predominately dystonic movement
disorder with elements of spasticity within the lower limbs.
He received Botulinum toxin bilaterally to his soleus and
gastrocnemius muscles one month after the accident. He was
nasogastrically fed until a gastrostomywas inserted 3months
post-accident for longterm nutrition. He was noted to have
severe gastro-oeophageal reflux and a jejunostomy extension
was performed 5 months after the accident to decrease his
risk of aspiration. Post-operatively, he developed abdominal
distension and poor gastric motility. An abdominal X-Ray
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(when he had had some bilious aspirates) showed pneuma-
tosis intestinalis and was treated with 2 week course of
Metronidazole. Constipationwas treatedwithMovicol. He had
episodes of autonomic instability with dystonia, leading to
increased secretions and raised temperature, diagnosed as
PAID and responding acutely to positioning, oxygen and
gentle physiotherapy. To improve his dystonia and decrease
his episodes of PAID, he was treated with Trihexyphenidyl,
Clonidine and Diazepam with gradual improvement. He was
referred for intrathecal bacofen pump insertion 6 months
after the accident but from an anaesthestic point of view, was
not considered stable enough for the procedure to take place.
He gradually improved and was discharged home 8 months
after the accident with a chair, a wheelchair, a profiling bed,
a sleep system and a hoist.
2.1.3. Sandifer syndromeSandifer syndrome, or dystonia secondary to gastro-
oesophageal reflux, oesophagitis or gastro-oesophageal dys-
motility, is common in children with neurological conditions,
including epilepsy, and it is always worth excluding in
patients with apparently intractable seizures as the dystonic
episodes can be very difficult to distinguish without video-
telemetry.39e41 Medical management of gastro-oesophageal
reflux may be effective, but some patients may need naso-
jejunal, or even intravenous, feeding for a period of time, or
fundoplication.
Case 5. A 3 year old boy with a history of West syndrome
presented with acute spasms considered initially to be
a recurrence. However the EEG did not show hypsarrhythmia
and the spasms were not accompanied by an EEG change. In
addition, the creatine kinase was elevated at 2200 IU/L. During
the admission it became clear that the spasms occurred after
feedingand thathewas inpainduringbolusgastrostomy feeds.
After a month of partial intravenous feeding, the spasms and
pain had settled and he could again be fed through his gastro-
stomy but continuously and with the tube in the jejunum. The
creatine kinase settled back into the normal range.
2.1.4. Rett syndromeIn addition to dysautonomic syndromes (case 2) and gastro-
oesophageal reflux, girls with Rett syndrome may have acute
dystonic life-threatening episodes. Trihexyphenidyl reduced
the frequency in 2 girls in one report; the third had died before
treatment could be offered.42
2.2. Cryptogenic acute dystonic syndromes
2.2.1. InfectionsAcute hemidystonia is typically secondary to arterial ischae-
mic stroke,43 often due to infections such as Varicella zoster or
Mycoplasma pneumoniae.44 These infections may also be asso-
ciated with generalised dystonia.45e47
2.2.2. Metabolic conditionsThere is a long list of metabolic conditions whichmay present
as dystonia, most presenting over a long period of time.8 Table
2 includes some of those which are treatable and present
acutely or episodically.
2.2.2.1. Leigh syndrome. Leigh syndrome commonly presents
as dystonia. Most, but not all, children have an abnormal MRI
(Fig. 1F) and high plasma and CSF lactate. Genetic testing and
muscle biopsy are usually required to make an accurate
diagnosis.48 Hypocapnia should be avoided if possible.49,50
Case 6. This boy presented with dystonia in the first year of
life and was noted to have putaminal abnormality on MRI
consistentwith Leigh’s disease (Fig. 1F), although therewas no
deterioration over a further 18 months of follow-up. However,
he presented encephalopathic with dystonic posturing in the
context of an acute influenzal illness and the MRI changes
were more widespread and characteristic of Leigh’s disease.
He could not be weaned from the ventilator and died in
hospital.
Case 7. At the age of 15 months, this girl was not quite
walking by herself although she did have a lot of words.
Following a febrile upper respiratory tract infection and
tonsillitis, she developed abnormal movements of her hands
and feet. At this stage she was very ill, in hospital and was
not sitting up although it is not certain that she was in coma.
She had a normal CT scan. She then made a good recovery
and was soon sitting alone. She subsequently walked on her
own without support by the age of two, although her speech
remained slurred. She had a further episode at the age of 3
years, again with a sore throat but only lasting a day when
she was unable to sit alone. A further CT scan was normal
and after about a week she returned to making progress at
her previous rate. At the age of five and a half, she developed
fever and an unsteady gait with speech changes. Her muscle
tone decreased, especially in the hip girdle and shoulders,
particularly involving biceps and deltoid. Muscle strength
was normal in the distal muscles of her hands. Her deep
tendon reflexes were sluggish but elicitable, her gait was wide
based and she had a lumber lordosis and a waddling gait with
weak hip girdle muscles. She was also noted to have oral
motor coordination difficulties. Her tandem walking was
normal, although heel toe walking was difficult because she
was weak. Creatine kinase was normal. Again she made an
apparently complete recovery but then presented encepha-
lopathic in the context of Mycoplasma pneumonia. She was
ventilated and on emerging from coma was extending her
arms and legs, although she remained hypotonic for some
time with areflexia. She then became hypertonic after the
first few weeks with severe equinovarus. MRI remained
normal on several occasions but she was found to have
recessive SURF-1 mutations, associated with cytochrome c
oxidase deficiency.
2.2.2.2. Organic acidaemias. Organic acidaemias, primarily
glutaric aciduria type 1, 3-methyl glutaconic aciduria, methyl-
malonic aciduria and propionic aciduria typically present with
dystonia or Parkinsonism8,51, and can usually be excluded by
undertaking urinary organic acids. All of these can presentwith
acute on chronic exacerbations.
Fig. 1 e Imaging in acutemovement disorders. A. Focus of T2-weighted high signal density in the left frontal whitematter in
a child with anti-NMDA receptor antibody encephalitis. High signal on T1-weighted imaging in a child presenting with
hemichorea and a raised antistreptolysin O titre. She recovered within 2 weeks on a combination of Penicillin and
Prednisolone. C1e3. Involvement of basal ganglia, white matter (B1 acute presentation aged 8; B2 3 months later) and
eventually grey matter (B3 representation aged 11) in a girl with positive antistreptolysin O antibodies. D. Radioisotope scan
in a child with opsoclonus-myoclonus. E. Lacunar infarct with in a teenager who developed Tourette syndrome after
cardiopulmonary bypass. F. Bilateral basal ganglia abnormality consistent with Leigh’s disease in a child with dystonia who
became unconscious in the context of H1N1 influenza. G. Moyamoya in a child with acute chorea. H. Eye-of-the-tiger’ sign in
neurogeneration with brain iron accumulation.
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3. Chorea
3.1. Symptomatic chorea
3.1.1. Post-cardiopulmonary bypass choreaChoreiform movements after cardiopulmonary bypass
surgery have been recognised for the past 30 years with an
incidence of 0.6e3% of those undergoing cardiopulmonary
bypass.52,53,54,55,56,57 Oro-facial dyskinesias are typical53,57 and
a Tourette-like syndrome, with simple and complex motor tics
and obsessive-compulsive behaviour, has been described (Fig.
1E).58 The onset is usually delayed by 2e7 days and most
patients have a clear period of normality between the operation
and the presentation with choreiform movements. The post
bypass chorea syndrome is commoner in those who have
undergone deep hypothermic ischaemic arrest,54,55,59 although
there is little evidence that the duration is important and it has
been reported in patients where this has not be the case.60
Relative polycythaemia may be a factor.61 MRI and CT scan in
the cases reported have been either normal, have shown
generalised atrophy or basal ganglia abnormality.54 Recent data
suggests that an alpha-stat method of pH management may
increase the chance of peri-operative complications, including
post bypass chorea, perhaps because the hypocapnia reduces
cerebral blood flow below the ischaemic threshold.56,62 Bron-
chopulmonary collaterals in patients with right ventricular
outflow tract obstruction and VSD also predispose to this
syndrome, and very rapid cooling has also been identified as
a risk factor. However it has been well documented that
patients have had choreoathetosis after cardiopulmonary
bypass without necessarily having any of the risk factors.
Improvement in the choreoathetoid movement is also typical,
although some patients have long term neurological
disability.63,64
Case 8. An 8 year old girl with pulmonary atresia with bron-
chopulmonary collaterals developed choreoathetosis after
palliative surgery. She made a good recovery over a period of
6 months and on neuropsychological testing one year later,
had a full scale IQ of 100, exactly the same as her twin sister
without congenital heart disease.
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3.1.2. Herpes simplex encephalitisChorea is unusual at presentation but may be an early sign of
relapse of Herpes simplex encephalitis. In addition to
continuation of antiviral treatment, plasma exchange,65 and
possibly other immunomodulation, may be considered.
3.2. Cryptogenic chorea
3.2.1. Sydenham’s choreaSydenham’s chorea remains the commonest cause of chorea in
childhood in the developed as well as the developing
World66e69 Between one and two thirds have carditis andmany
also have tics and psychological symptoms, such as anxiety,
sleep problems or obsessive-compulsive disorder.70e72 Neuro-
imaging is typically normal but may show non-specific abnor-
mality, while children with more severe post-streptococcal
acute movement disorders may have white and gray matter
involvement. (Fig. 1B and 1C1e3). Around one third relapse.
Penicillin should be given and bed rest is recommended.73
There is some evidence that immunotherapy with predniso-
lone or immunoglobulin is associated with more rapid resolu-
tion of the chorea.69,73e78 Sodium valproate or carbamezepine
often reduce the chorea.
Case 9. A 6 year old boy presented with choreoathetosis and
tics after a throat infection and had a raised antistreptolysin O
titre and a markedly elevated anti-DNase B level. He woke at
night feeling frightened and anxious and had symptoms
compatible with an obsessive-compulsive disorder. He was
treated with Penicillin and Prednisolone and made a good
recovery but had 3 further relapses with frequent tics during
intercurrent infections which were associated with positive
anti-basal ganglia antibodies and responded to steroids and
clonidine whichwereweaned successfully each time after the
tics resolved, in addition to long-term Penicillin.
Case 10. An 8 year old girl presented with headache, persis-
tent head and eye deviation to the right, left facial weakness,
and ataxia a fewweeks after she had chickenpox. MRI showed
symmetrical T2 high signal and swelling of the basal ganglia,
involvement of midbrain, and cortical signal abnormalities,
but no cerebellar involvement (Fig. 1C1). She was diagnosed as
having acute disseminated encephalomyelitis (ADEM) and
improved slightly after treatment with steroids and immu-
noglobin and substantially after plasma exchange so that she
resumed mainstream school, although she remained ataxic
with some residual left arm dystonia and dysarthric speech.
An interval MRI showed mildly atrophic basal ganglia with
slightly increased signal and a few cortical signal abnormali-
ties (Fig. 1C2). There was sparing of the thalami, midbrain and
cerebellum. At the age of 11 years, she presentedwith a 2week
history of abnormal movements, further regression of motor
skills, and difficulties with feeding, swallowing and speech.
On examination, she had generalised rigidity, dystonia with
choreiform movements , drooling, poor sitting balance, brisk
reflexes, and intermittent restriction of upward eye gaze.
There was no intelligible speech but she had a good level of
comprehension and non-verbal communication initially.
However, she deteriorated in the next few weeks, requiring
nasogastric feeding, and eventually becoming bed ridden and
emotionally labile with increasing rigidity and dystonia.
Further MRIs showed fluctuating grey matter abnormalities
with preferential involvement of the basal ganglia and arterial
watershed zones, very unlike ADEM (Fig. 1C3). There was no
response to further treatment with steroids and immunoglo-
bin. Despite extensive investigation, the only abnormalities
were a raised ASOT and AntiDNAse B and a diagnosis was
made of Poststreptococcal Acute Disseminated Encephalo-
myelitis with Basal Ganglia Involvement.78 She made a partial
recovery after further plasma exchange and continues to
improve during a course of Cyclophosphamide.
3.2.2. Systemic lupus erythematosusNeurological complications are common at presentation with
systemic lupus erythematosus in childhood.79e82 Chorea is
most frequent in childhood but occurs in <10% of cases.83e86
Other typical symptoms include headache, behavioural
disorders including confusion, depression, anxiety and
psychosis, lethargy, diplopia, blurred vision, memory alter-
ation, dizziness and altered consciousness. The most
frequently observed neurological signs in addition to the
possibility of chorea, tremor or rigidity are cranial nerve palsy,
ataxia, papilloedema, nystagmus, meningism, myelopathy,
neuropathy and cortical blindness. Presentation with
seizures, status epilepticus or coma is not uncommon. More
subtle presentations include progressive cognitive dysfunc-
tion and idiopathic intracranial hypertension. Ischaemic or
haemorrhagic stroke is obvious in 15e30% of those with
neurological complications and may be associated with arte-
rial abnormality, but in most of the presentations the possi-
bility of venous sinus thrombosis should be excluded. The
presence of the lupus anticoagulant on laboratory testing is
associated with chorea.87 Anticoagulation is usually appro-
priate for those with antiphospholipid syndrome, particularly
if thrombosis has occurred.87 Prednisolone, hydroxy-
chloroquine and cyclophosphamide may be required.
Case 11. A 15 year old girl presented with poor appetite,
lethargy, weight loss and arthralgia and was diagnosed with
Systemic lupus erythematosus. She developed sudden onset
severe chorea three days after she was commenced on
hydroxychloroquine. Cortical vein thrombosis was considered
and she was commenced on IV heparin infusion but the MRI,
including susceptibility-weighted imaging, did not show
definite evidence. The heparin infusion was changed to
subcutaneous clexane and her anti Xa levels were in the
acceptable range. She was also commenced on levatiracetam
and clonazepam which were gradually weaned off. She
initially received IV methylprednisolone which was changed
to oral prednisolone which was eventually weaned to low
dose on alternate days and she had monthly cyclophospha-
mide infusions for 6 months.
Case 12. A girl presented at the age of 12 years with an
episode of severe headache with bilateral papilloedema. MRI
brain scan was normal and opening pressure on lumbar
puncture was high, so she was diagnosed with idiopathic
intracranial hypertension. Two months later she developed
chorea involving her left sided limbs, mainly her arm, fol-
lowed by right side chorea. The working diagnosis at the time
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was Sydenham’s chorea. Her movements normalised and she
was asked to continue on penicillin prophylaxis. At the age of
16 years, she presented with sudden onset of left sided
weakness and sixth and seventh nerve palsies. MRI and MRA
showed right middle cerebral artery (MCA) occlusion with
MCA territory infarction. Echocardiography was normal with
no intracardiac thrombus. She had a low platelet count and
abnormal clotting so she was investigated for an autoimmune
aetiology. She had a high ESR (42e80) and showed positive
Anti-Nuclear Antibody, anticardiolipin antibody, and lupus
anticoagulant, and low C4 (complement). Direct antiglobulin
test was positive, and although therewas no other evidence of
haemolysis, she was given a short course of low-dose pred-
nisolone. Shewas anticoagulatedwith lowmolecular heparin,
followed by warfarin to keep her INR between 3e4. She was
rehabilitated and has been followed for 5 yearswith no further
neurological complications.
3.2.3. Anti-N-methyl-D-aspartate receptor (NMDAR)encephalitisAn acute encephalopathy with a prominent movement
disorder, typically dyskinesia, dystonia and chorea, has been
recognised for some time.88,89 Recently anti-N-methyl-D-
aspartate receptor (NMDAR) encephalitis has been recognised
in adults, typically women with a mean age of onset of 25.8
years and often (60%) with ovarian teratomas; resolution is
common following removal. Children, the majority girls, have
been described, typically presenting after infections and with
no evidence of malignancy90e92 Clinical features include
psychiatric symptoms including personality change, irrita-
bility, anxiety, aggressive behaviour, delusional thoughts, and
short-termmemory loss. Additional features include partial or
generalized seizure activity and a movement disorder, most
frequently orofacial dyskinesia. Imaging may show non-
specific changes and the diagnosis is made by demonstrating
the antibody in serum, and if necessary, CSF. The prognosis
may be good in many cases but many paediatricians have
treated with steroids, immunoglobulin, plasmapheresis and
cyclophosphamide.93
Case 13. A previously healthy 26 month-old girl presented
with a one-week history of unsteady gait and mood lability
preceded by a viral prodrome several weeks previously.
Clinical progression, with regression of speech and
language and motor skills, ensued leading to a florid
movement disorder by the third week. She developed oro-
facial dyskinesia, choreoathetoid right arm movements,
ballistic leg movements and left upper limb dystonia
requiring frequent sedation. There was a subtle focus of T2
and proton density high signal in the left frontal white
matter (Fig. 1A). EEG demonstrated persistent diffuse,
generalised slow activity. Screening for occult malignancy
was negative. Clonazepam infusion had marginal benefit.
She was subsequently managed with high dose steroids
and immunoglobulin infusions with only partial thera-
peutic response. With confirmation of very high anti-NMDA
serum antibodies, monthly pulsed cyclophosphamide
infusion was commenced. She promptly made an excellent
functional recovery and her neuro-developmental profile is
age-appropriate eighteen months later.
4. Myoclonus
Myoclonus may present acutely days, months or years after
hypoxic insults,94 is sometimes a feature of post-infectious
encephalopathies95 and is a common presentation in those
with a conversion disorder.4,5 The important syndrome in
previously well children is acute opsoclonus-myoclonus and
the priority is to exclude neuroblastoma.
4.1. Opsoclonus-myoclonus
This is a rare condition with an incidence in the United
Kingdom of 0.18 cases per million total population per year.96
Hospital-based series of children with opsoclonus-myoclonus
have found neuroblastoma in over half the cases97,98 but the
population-based study found this condition in just over
a quarter.96 The neuroblastoma is typically stage I/II and may
be cured by surgery alone, suggesting that the opsoclonus-
myoclonus may be an auto-immune phenomenon.99 Urine
for Vanillyl mandelic acid (VMA) and radioisotope imaging
(Figure 1D) should always be undertaken but removing the
neuroblastoma does not cure the opsoclonus-myoclonus.100
The movement disorder may also be triggered by infections
and vaccines101e105 and has been reported as a presentation of
coeliac disease.106 The associated developmental delay and
behavioural disorder is often very prominent and difficult to
manage.96,98,100,107 In patients with or without neuroblastoma,
there is a little evidence for benefit with immunomodulation
using steroids, cyclophosphamide, microphenolate or rit-
uximab,108e115 ideally started as early as possible after
presentation. The results of the planned European trial are
eagerly awaited. Some patients may benefit from
Clonezepam.116
Case 14. A previously well boy presented with opsoclonus-
myoclonus at the age of 18 months in the context of an
upper respiratory tract infection. Neuroblastoma was not
found despite extensive imaging. He was treated initially
with Prednisolone 2 mg/kg which controlled the eye
movements and was therefore weaned. However the
movement disorder returned on weaning and his behav-
iour deteriorated and remained poor when the steroids
were increased again. His developmental progress pla-
teaued. After considerable discussion with the parents, 6
monthly cycles of Cyclophosphamide were given with an
impressive improvement in developmental trajectory and
behaviour.
Case 15. A 2 year old presented with ataxia in the context of
an upper respiratory tract infection and recovered over the
following month without sequelae. Four months later, she
presented with opsoclonus-myoclonus and urinary VMA was
high. Imaging showed a small neuroblastoma which was
surgically removed. The opsoclonus-myoclonus resolved on
Prednisolone and she made normal developmental progress
with no behavioural problems. She had several similar infec-
tions without relapse but had a further episode one year after
the initial presentation, which also responded quickly to
Prednisolone.
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5. Parkinsonism
This is a relatively rare acute presentation, although some
patients with post-infectious movement disorders secondary
to influenza, EpsteineBarr virus, Streptococcus pneumonia and
M. pneumoniae may have features45,117e120 sometimes with
clinical signs and neuroimaging compatible with acute
disseminated encephalomyelitis, encephalitis lethargica121 or
acute necrotizing encephalopathy.122e125 Anti-MMDA
receptor encephalitis should be excluded.126 In the devel-
oping world, Japanese B encephalitis,127 tetatnus and rabies
may be causes. Hypocalcaemia, hypomagnesaemia128 and
carbon monoxide poisoning117,129,130 should be excluded
urgently. There are a number of important genetic conditions
which require exclusion131e133 (Table 2), although as testing is
very expensive, it is wise to ask for clinical advice over likely
diagnoses at an early stage.131e133 Early speech and language
therapy assessment over the method of feeding is advisable,
in addition to physiotherapy and occupational therapy.
Correct diagnosis of Parkinsonism may mean that exacer-
bating drugs are avoided.134,135 Most children do not require
specific drug treatment for the movement disorder in the
acute phase but antibiotics and antivirals and immunosup-
pression should be considered if there is an infectious or
autoimmune cause and benzodiazepines are probably safe.
Amantadine is an antiviral which is no longer used for influ-
enza treatment as there is widespread resistance136 but it may
have a role in acute Parkinsonism in childhood134 and is being
trialled in ABI.137 Levodopa/carbidopa has been used,134,135,138
but gradual spontaneous improvement is common and
dopaminergic drugs may need to be withdrawn rapidly if
other acute movement disorders appear in the convalescent
phase.134,135
Case 16. This previously well 3 year old boy presented
following a short history of temperature, vomiting and diar-
rhoea. He then became encephalopathic, refused to walk,
stopped eating and speaking and required a nasogastric tube
to manage his fluid requirements. On admission he was irri-
table, with a paucity of facial movements and difficulty in
initiating movements, particularly of his left arm. He was
encephalopathic with abnormal interaction with those
around him, no speech and was unable to walk with low
central tone although his peripheral tone, power and reflexes
were normal. Hismother had an admission at a similar age for
a neurological condition which has left her with some subtle
difficulties, including ataxia. Extensive metabolic testing was
negative and genetic testing is in progress.
Case 17. This teenager had an acute deterioration in writing
and began blinking very frequently. Referral was precipitated
because he began to require feeding by hand, taking up to
three hours per meal. He had walked and spoken early but
always had a stammer. On examination, he had blepharo-
spasm and intermittent rigidity and a lot of difficulty in initi-
atingmovement, with a bent head and a shuffling gait. He had
impaired dopamine and serotonin turnover and some
evidence of tetrahydrobiopterin deficiency. There was also
a minimal increase in 3-methyldopa. In view of this, aromatic
amino acid decarboxylase deficiency was briefly considered
but plasma enzyme analysis did not support this diagnosis. A
problem with tetrahydrobiopterin availability was considered
but a phenylalanine loading test was negative. He was anti
basal ganglia antibody positive. He had a partial response to L-
Dopa and is under investigation for genetic causes of juvenile
Parkinsonism.
6. Conclusion
There is a wide differential diagnosis in children presenting
with acute movement disorders. Once drug effects and
presentations related to psychological distress have been
considered, it is essential to investigate previously well chil-
dren for conditions with an infectious and/or immunological
basis so that therapy, including intensive care, can be appro-
priately considered for the individual patient. There should be
a low threshold for antibiotics and immunomodulation
should be discussed early. Feeding disorders are often prom-
inent at presentation, so a multidisciplinary approach to
rehabilitation including speech and language as well as
physiotherapy, occupational therapy, specialist nursing and
access to advice from adult neurologists is essential, whether
or not there is an organic basis. European and International
collaboration will be needed to develop the evidence base for
managing this important group of conditions.
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