Ataxia in children

1. PRESENTATION BY DR.VIJAY BHASKAR
MODERATOR:DR V R ANAND
*

2. DEFINATION

3. HISTORTY AND EXAMINATION
OF MD

4. TYPES OF MD IN CHILDHOOD

5. CHOREA

6. ATHETOSIS

7. TREMORS

8. DYSTONIA

9. APPROACH TO DIAGNOSIS

10. DIFFERENT FROM SEIZURES

11. MDs and Their Anatomical
correalation

12. DRUGS INDUCED MDs

13. INHERITEDABLE CAUSES OF MDs

14. TREATMENT FOR MDs

15. ATAXIA
literal meaning -without order
clumsiness
loss of co-ordination

16. BASIC ETIOLOGY

17. Cerebellar Dysfunction:
Anatomy

18. Wide based stance & Gait
Gait- staggering, irregular steps, lateral veering.
Cerebellar gait -visible or more prominent
Sudden turn, Abrupt stops , Tandem walking
Ataxic sensory gait
brisk leg movements
legs placed far apart to correct instability
steps of variable length
need for carefully watching the ground.
+ve Romberg's sign .
Most of the autosomal recessive and dominant ataxias and with a
known genetic defect are characterized by the coexistence of
cerebellar and sensory ataxia
STANCE AND GAIT

19. Asynergia- movements are broken into isolated subsequent
steps , lack easiness/ smoothness
Dysdiadochokinesia- impaired REM
Dysmetria. there is an abnormal excursion in movements and
errors in reaching a precise target
Tests
finger-to nose, the finger-chase tests for the upper limbs
heel-to-knee and heel-to-tibia tests for the lower limbs.
In coordination due to cerebellar disease is associated
with abnormal speed of the movements
to an excessive rebound phenomenon when an opposed motion
is suddenly released. ( due to a delay in contraction of the
muscles, which normally would arrest the flexion of the limb)
Speed of initiating the movement is also slow and there is
irregularity in both acceleration and deceleration of
movements
LIMB COORDINATION

20. Hypotonia is a typical cerebellar sign.
Wider excursion of hands on shaking the arms.
Obliteration of the space between the volar aspect of the wrist
and the deltoid.on a forced flexion of the arm at the elbow.
In ataxic patient, the hypotonia is not a constant clinical sign.
Present in FRDA1 patients, “pure” cerebellar syndromes-
SCA6, 10, and 11 subtypes.
In some other spinocerebellar disorders normal or increased
muscle tone may also be found - SCA3 or MSA
MUSCLE TONE

21. Smooth pursuit movements
Saccades
Certain clinical cerebellar syndromes might have characteristic
patterns
FRDA1- fixation instability , square wave jerk, consistently
undershoot or overshoot the target during horizontal saccadic
eye movements (saccadic dysmetria)
ABL -progressive paresis of the medial rectus muscles with
nystagmus of the adducting eye on lateral gaze was observed
AR ataxias (some ) Oculomotor apraxia
AD ataxias-
Fragmentation of smooth pursuit movements,
Saccadic dysmetria
Nystagmus
Saccadic slowing SCA1, SCA2, SCA3, SCA7, and SCA17
ophthalmoplegia -SCA2 SCA1 and SCA3
OCULAR MOTOR FUNCTION

22. ETIOLOGY

23. Mendelian AR and AD ataxias have a higher frequency than other genetic
ataxias.
Prevalence – 1/50,000 - Friedreich’s ataxia (FRDA1)
1/100,000 - Ataxia Telangectasia (AT), dominant SCAs
AR ataxias
Multi-system disorders with extra-neural signs and symptoms - FRDA1
Main mechanisms - loss of protein function,
the control of energy output and oxidative stress -FRDA1, AVED, ABL,
possibly Cayman ataxia;
the control of DNA maintenance and the cell cycle -AT, AOA1 and
AOA2, SCAN
AD ataxias - restricted to the central nervous system.
Mutant protein with a longer-than-normal poly glutamine stretch.
Toxic gain-of-function of the aberrant protein
Longer expansions-earlier onset, more severe disease in subsequent
generations
Diagnostic pathological feature-OPCA-(most common presentation of
SCA+)
AD episodic ataxias (EA)
Point mutations in the potassium channel gene, KCNA1,- EA 1
Point mutations in the CACNL1A4 gene - EA2
GENETIC ATAXIA

24.  Spinocerebellar
Ataxias
 Adult-onset leukodystrophy
 Branchial myoclonus &
Spastic paraparesis
 CAPOS syndrome
 Deafness & Narcolepsy
 DRPLA: DRPLA protein;
CAG repeat;12p13
 Episodic ataxia
 with Myokymia (EA1):
KCNA 1; 12p13
 Paroxysmal (EA2):
a1A Ca++ channel;
19p13
 with Choreoathetosis &
Spasticity: 1p
 Holmes ataxia
 Mental retardation: 19q13
 Multiple hamartoma
syndrome: PTEN; 10q23
 Myelocerebellar Nystagmus
 Parenchymal degeneration
 Prion disease: Prion
protein; 20p12
 Spastic ataxia
syndromes
 Thermoanalgesia & loss of
fungiform papillae
 Tremor, Essential: 3q13
 Vermal aplasia
 Von Hippel-Lindau
Syndrome: VHL protein;
3p26

25.  Ataxia Telangectasia:
ATM; 11q22
 Ataxia telangectasia-like:
MRE11; 11q21
 Baltic Myoclonus
(Unverricht-Lundborg):
Cystatin B; 21q22
 Cayman ataxia: 19p13
 Cerebelloparenchymal
disorders (CPD): II, III, IV,
V
 Charlevoix-Saguenay -
Spastic Ataxia: Sacsin;
13q12
 Cockayne Syndrome (5)
 Cytochrome c Oxidase I
 Early onset with retained
reflexes (EOCA): 13q12
 Friedreich ataxia: 9q13
 Infantile Onset
Spinocerebellar Ataxia:
10q23
 Leukoencephalopathy with
vanishing white matter:
3q27
 Marinesco-Sjögren
 Posterior column + Retinitis
pigmentosa: 1q31
 Salla syndrome: SLC17A5;
6q14
 Vitamin E deficiency: a-
tocopherol transfer protein;
8q13
 Xeroderma pigmentosum
 Other Congenital ataxias
• DNA repair defects
•
Metabolic,Mitochondrial
• Multisystem
disorders

26. CLINICAL SYNOPSIS Gene Map Locus: 9q13 GAA 66->1700 ( N< 42)
Neurological: Cerebellar ataxia
Dysarthria
Nystagmus
Incoordined limb movements
Diminished or absent tendon reflexes
Babinski sign
Impaired position & vibratory sense
Hypoactive knee and ankle jerks
Cardiac : Hypertrophic cardiomyopathy ,CHF, Muscular subaortic
stenosis
Skel : Pes cavus , Scoliosis, Hammer toe
Metabolic : Diabetes mellitus
Lab : Abnormal intranscription of protien FRATAXIN (resposible for Iron
efflux from mitochondria)
Abnormal- motor and sensory nerve conduction, EKG, ECHO,MRI
FRIEDREICH ATAXIA

27. Accurate family history
Look for anticipation- earlier onset , heavier clinical
expression in subsequent generations ( SCA 2,7)- gene
mutated parent is still asymptomatic or died before developing
clinical symptoms.
Consanguity - recessive
Age of onset – earlier in AR( exceptions-late onset FRDA1,
infantile cases of SCAs e.g. SCA2, SCA7)
Origin of families-
SCA3 - Portugal, Brazil, India, rare in Italy SA
AVED – Southern Mediterranean
AOA1 – Portugal, Japan
Cayman Ataxia- Grand Cayman Island
CLINICAL HISTORY

28. History & Physical Examination
Careful family history
Standard laboratory including lipids and thyroid
MRI Brain
Autonomic testing ( Sphincter EMG)
Genetic testing
Toxic screen, Vitamin E
Antibodies- paraneoplastic, antigliadin
EVALUATION

29. THANK YOU