Category Archives: Neurology

Sacral dimple

Clinical, Congenital, General paediatrics, Neurology

Typical sacral dimples are <5mm in diameter, within 25mm of anus and located in midline.  Rate of spinal  dysraphism (bifida occulta) less than 1%.

Higher risk if do not fulfill these criteria. Lipomas, deviated/bifurcated crease are the most likely to be associated with dysraphism.  Otherwise you expect at least 2 or more cutaneous markers (hair tuft, haemangioma, Mongolian spot, skin tag/tail).

Reports of high frequency of hair tufts in diastematomyelia probably refer to more striking lesions (“faun tails”).

Royal College of Radiology has policy  – ignore sacral dimples unless atypical, or in combination with other lesions.

USS if neonate, but MRI if US abnormal or equivocal, where neurological signs (bladder, bowel, lower limb) or lesion discharging.

[Arch Derm 2004]

Episodic autonomic symptoms

Clinical, General paediatrics, Neurology, OPD

Dyspraxia, or Developmental Coordination Disorder (DCD)

Community, General paediatrics, Neurology, OPD

Developmental Co- ordination Disorder (DCD), as outlined in DSM IV (American Psychiatric Association 1994):

  • Performance in daily living activities that required motor co-ordination is substantially below that expected given the person’s chronological age and measured intelligence. This may be manifested in delays in achieving motor milestones (i.e. walking, crawling, sitting) dropping things, ‘clumsiness’.  Significantly interferes with academic achievement or activities of daily living.
  • The disturbance is not due to a general medical condition (e.g. Cerebral Palsy, Hemiplegia or Muscular Dystrophy), and does not meet the criteria for a pervasive Developmental disorder.
  • If Global Learning Difficulties are present the motor difficulties are in excess of those associated with it.

It is essential that early referral is made in order that children do not develop behavioural difficulties due to their frustration at not being able to carry out the same tasks as their peers.

Clues are:

  • Does the child’s motor skill appear to be behind their cognitive skills?
  • Dose the child appear to move generally in an uncoordinated way i.e. walking, running, manoeuvring around objects?
  • Does the child fall over constantly, bump into things, and /or knock thing over?
  • Has the child developed a dominant hand i.e. does he/she prefer to use one hand for more tasks?
  • Does the child have difficulties with dressing especially organising themselves? Do they find laces, small fastening and cutlery difficult?
  • What is their attention span like? Are they always fidgeting or squirming?
  • Are they having significant difficulties in the classroom in relation to their peer e.g. poor behaviour, avoidance of tasks, poor handwriting, dislikes gym?

N.B  Most children in their early school years will demonstrate one (or more) of these areas of difficulty but this does not mean they all have DCD!  Children with DCD will present with many of the difficulties above for a prolonged period.

Tic Disorders and Tourette Syndrome

General paediatrics, Neurology, OPD

Tics are recurrent, sudden, non-rhythmic twitches. Can be in 1 muscle or muscle group, but can also be a more complex semi-purposeful movement, or even present as a bizarre gait. Typically affect face (eg blinking, grimacing), neck, shoulder.  Can be more complex sequences of movements. Characteristics are:

  • Tend to be situational, with stress making them worse.
  • Initially they are suppressible, although depending on the situation this suppression can be virtually effortless! Usually though, suppression leads to rising anxiety and then a rebound in frequency.
  • There is often a premonitory feeling.
  • They can be suggestible.

Differential includes stereotypy, spasms, chorea.

Although tics can wax and wane over time, there is a general tendency to improve, and they are very unusual in adulthood.

Tics occur most commonly in boys. Usually they are transient, lasting for between 4 weeks and 1 year. A chronic tic disorder does exist distinct from Tourettes.

Vocal tics (clearing throat, yelps, coughs, sniffs, grunts) can occur in isolation, but a combination of vocal and motor tics suggests Tourette’s syndrome.

Tourette’s syndrome

Thought to affect 1% of children, so probably a lot subclinical! An inherited neuropsychiatric condition, it starts at a mean age of 7 but can be as young as 2yrs. Motor tics come first, about a year before vocal tics. Complex vocal tics may be seen but contrary to public understanding, most kids do not swear (coprolalia)!

Definition requires that motor and vocal/phonic tics are present (at some point) for at least a year, on a daily basis, with onset prior to 18yrs, in absence of substance misuse, medical condition or medication.  The characteristic features of Tourette’s are:

  • Echolalia – repeating phrases
  • Palilalia – repeating other people’s words
  • Coprolalia – swearing or abusive language. Involuntary, and causes distress to the patient, who will often try to conceal the outburst by coughing, etc.
  • Copropraxia – making obscene gestures
  • Palipraxia – imitating other people’s gestures

Tics wax and wane, evolve over months.  Can be self harming eg scratching, rubbing, head banging, punching, poking, stabbing oneself (see also obsessive compulsive co-morbidity below).

In some patients, there is a non-obscene compulsion to shout socially inappropriate things (NOSI).  Often worsens around puberty. 50% abate after puberty, but mostly just better self-management?

Differential is basal ganglia or cerebellar abnormality eg post-encephalitis, Huntingtons.  Investigations only necessary where unusual deterioration or progression of symptoms.

Co-morbidity

Pure tic disorder is unusual in Tourettes. 85% have comorbidity, most commonly:

  • Obsessive Compulsive Disorder/Behaviour – less to do with cleanliness, more sexual/religious/violent themes, orderliness, symmetry, checking, counting, forced touching.
  • Self-injurious behaviour is well described (see above)
  • ADHD
  • Conduct disorder, affective disorders more rarely.

The comorbidities are often more significant on school performance than the tics.  Comorbidities are common in relatives, even if tics are not.

Treatment

Counselling is useful for self-esteem, anger management, and social functioning. Habit Reversal Training is effective but not widely available – officially 12 weekly hour sessions, need to recognize premonitory urges and then replace tic with controlled movement, or position self to prevent tic (eg chin on chest to prevent shouting).

Drug treatment may be considered eg self harming, but not much evidence for effectiveness.  Traditional or atypical neuroleptics, or clonidine (esp where behaviour or sleep problems) used.

Deep brain stimulation being researched.

Prognosis

Tic frequency and severity decline with age in a large proportion of patients (59–85%).

Predictors of NOT improving include higher childhood tic severity, smaller caudate volumes and poorer fine motor control.

The presence of untreated comorbid psychopathology, such as ADHD and OCD, can adversely affect the long-term outcome of patients with TS.[Funct Neurol. 2012 Jan-Mar; 27(1): 23–27. ]

Tourettes Action parent support group.

[Stern, Curr Peds 2006:16:459]

Multiple sclerosis

Genetics, Neurology

Only 3-5% of cases of MS have symptoms before the age of 16. Most have a relapsing-remitting course, particularly in the beginning, typically with one to two relapses per year. The frequency of attacks does seem to predict disease severity and earlier evolution to secondary progressive phase.

Although it takes longer in kids to develop persistent disability, they still develop it at a relatively young age, for example the third or fourth decade of life. That is of course going to have significant effects on life course, including work and family life.

Even at onset, cognitive function is often reduced, which will also affect education and socialisation. So clearly there is interest in disease modifying treatments.

Presentation in younger children often follows an infectious illness. Cognitive impairment is more common relative to older kids.

Investigations

MRI of brain and spine, looking for demyelinating lesions.

Monoclonal bands in CSF.

Treatment

Steroids 10-30mg/kg for 3-5 days effective. No good evidence for IVIG. Where acute life threatening symptoms, plasmapheresis may be effective where steroids fail.

In adults good evidence for interferon Beta in relapsing-remitting disease, IM or SC depending on product, reduces relapse rate and probably slows progression of disability. Glatiramer is a synthetic product with similar effects.

Second line treatments in adults include Natalizumab, mitoxantrone and cyclophosphamide.

Differential diagnosis

  • lysosomal storage disorders,
  • various mitochondrial diseases,
  • other neurometabolic disorders,
  • Krabbe, Metachromatic leukodystrophy, X-linked adrenoleukodystrophy, Fabry, Niemann-Pick C, Chidak-Higashi.  [Clue is in the name, leukodystrophy]

Since these are genetic conditions, essential for management and genetic counselling.

J Weisfeld-Adams http://brain.oxfordjournals.org/content/138/3/517

Leigh disease

General paediatrics, Genetics, Neurology

Infantile subacute necrotizing encephalopathy.

Clinically heterogenous, lots of different genes.  Can be X-linked, mitochondrial or recessive!!!  Main genetic problem is mitochondrial complex defect, but same disease can be caused by pyruvate dehydrogenase defect (actually a complex of enzymes).

Baby’s initial development may appear normal, although there may be failure to thrive.  Lactate can be raised in serum.  Progressive, often rapid, neurological deterioration including hypotonia, dystonia, seizures.

Lesions (necrotic, gliosis, spongiosis) seen in basal ganglia, brainstem, cerebellum, spinal chord.  CSF lactate and pyruvate may be raised, even if serum normal.

See mitochondrial inheritance.

 

Valproate – MHRA warning

General paediatrics, Neurology,

Updated December 2023 –

High risk of serious developmental disorders if exposed in womb (up to 30-40% risk, including 5x higher risk of autism) and congenital malformations (10%), including:

  • Spina bifida
  • face/skull malformations, including cleft lip/palate
  • Limb, heart, kidney, genital abnormalities
  • Deafness

In boys, pre-clinical data on transgenerational risks, and animal studies suggesting infertility.

Oral Valproate must not be started in new patients (male or female) younger than 55 years, unless two specialists independently consider and document that there is no other effective or tolerated treatment, or there are compelling reasons that the reproductive risks do not apply.”

Patient guide and checklist available.

Encephalopathy with Status Epilepticus during Sleep (ESES)

General paediatrics, Neurology

Poorly understood complication of some epilepsies.

Clinically, global regression esp cognitive and behavioural, associated with paroxysmal epileptic activity during sleep, which may of course not be recognized.  The classic example is Benign Rolandic Epilepsy, where continuous spike waves develop druing slow wave sleep (CSWS).  Also seen in Landau Kleffner syndrome.

The problem can be unmasked by anti-epileptic medication, especially carbamazepine.  Appears to be associated with brain pathologies eg polygyria, migrational disorders plus some chromosomal problems eg 8p-.

Diagnosis should be considered when unexpected cognitive impairment (eg memory, temperospatial skills, language) or behaviour changes (eg hyperactivity, aggression, disorientation).  Motor impairments eg ataxia and dystonia have been described.

Investigations

Dramatic increase in EEG abnormalities of any kind during sleep.

Treatment

Traditional plus newer AEDs have been used, but evidence does not point to any one being superior to any other.

Steroids appear to be effective – unclear whether ACTH or hydrocortisone better.

Outcome

Poor prognosis (ie long term neuropsychiatric problems) appear to be associated with longer duration of ESES, plus frontal neuropsychological deficits and frontal EEG anomalies.

[Epilepsy Research and Treatment 2012 http://dx.doi.org/10.1155/2012/642725]

Benign Rolandic Epilepsy (BECTS, or CECTS)

General paediatrics, Neurology

Latest name “Childhood Epilepsy with centrotemporal spikes”. Not always benign…

Common form of childhood epilepsy, with some characteristic features:

  • Seizures usually in sleep
  • If awake, then start with symptoms in one side of the mouth/tongue eg tingling
  • Speech may be impaired, with gurgling noises, as throat muscles affected – child may be trying to indicate something weird is happening to them!
  • Then twitching of face, spreading to face and arm
  • Can have tonic-clonic seizures
  • Characteristic centro temporal EEG abnormalities.  May need to be done sleep-deprived to provoke.
  • Although focal, MRI not indicated if typical features.

Treatment not always required, many children only ever have one or two seizures! Benign, because almost always goes away in puberty viz before age 16.

NICE recommends treatment with carbamazepine or lamotrigine as first-line treatment.

Be aware that carbamazepine and oxcarbazepine may exacerbate or unmask continuous spike and wave during slow sleep, which may occur in some children with benign epilepsy with centrotemporal spikes.

If these are ineffective, alternatives would be levetiracetam, oxcarbazepine or sodium valproate.

Bell’s palsy

General paediatrics, Neurology

bells palsyDiverse causes, some of which are extremely serious (mostly infiltrative):

  • Zoster sine herpete ie zoster reactivation without vesicles – probably responsible for a third of otherwise unexplained facial palsies
  • EBV- the most commonly found cause (20%)
  • Ramsay Hunt – look out for soft palate, tongue as well as external auditory meatus lesions
  • Mycoplasma
  • Cat scratch disease, HIV, Lyme disease (erythema chronicum migrans, travel history)
  • Acute otitis media (historically the most common cause!  Reactivation of virus?  Toxin induced demyelination?  But beware mastoiditis!)
  • Trauma
  • Malignancy – leukaemia, cerebellar astrocytoma, rhabdomyosarcoma
  • Histiocytosis
  • Haemophilia
  • Hypertension!

Bell’s Palsy is what you would call it if idiopathic, but perhaps you just haven’t looked hard enough? Often otalgia, facial or retroauricular pain. Typically mild except in Zoster, where it is severe. Pain may precede palsy.

Warning signs (for a serious underlying cause) are:

  • otitis media (in case direct inflammation, ie osteomyelitis),
  • hearing loss,
  • lymphadenopathy, tonsillar enlargement (parotid tumour),
  • mastoid enlargement,
  • frontal sparing, motor function of tongue/fingers (adjacent cortical representation) (UMN lesion)
  • or duration longer than 1 month.

Assess using House-Brackmann scale:

House Brackman criteria

Management

Do hearing test, blood pressure, check frontal sparing/tongue/finger function. FBC if any suspicion of leukaemia. Check blink reflex (prognostic).

Treatment

Apply lubricating drops hourly during day, and an ointment overnight. Patching seems to be frowned upon now.

Treat underlying cause!

For Bell’s, still controversial.  Cochrane review (2016) found that steroids reduce chance of permanent facial weakness (NNT=10), involuntary movements (motor synkinesis) and crocodile tears.  Adding antivirals may improve rate of recovery but low quality evidence – certainly less good than steroids, in fact not much different from placebo when used alone! Even without treatment most make a full recovery within 9 months. (Dundee study in adults, NEJM 2007; 357:1598 PMID 17942873)(Adour, Ann Otol Rhino 1996)(Hato Otol Neurotol 2003, PMID 14600480)

Only 2 studies in children from what I can see.

IV aciclovir in Ramsay Hunt since poor prognosis. Valciclovir would in theory be better, 96% recovery in Hato study (5 day course with steroids cf steroids alone) but unblinded (Otol Neurotol 2007;28:408-13)

Some evidence for methylcobalamin and hyperbaric oxygen.

Recovery usually within 3 weeks, else nerve regeneration takes 4-6 months. Beyond 6 months improvement is unlikely. For long term palsy, feedback training, surgical techniques may result in functional as well as cosmetic improvements. Synkinesis and facial spasm are complications, treat with botulinum. (BMJ 329:553)