Pediatric Neurology Quick TalksAtaxiaMichael BabcockSummer 2013

Scenario2 yo girlAcute onset of not walking every since waking this morningCrying and trying to be carriedNo feverNo recent witnessed traumaNo erythema, no pain with palpation of extremitiesHx of normal development, walking for 8 months.Awake and alert, but fussy

Refusal to Walk (or abnormal gait/limp)Infections septic arthritis, osteomyelitis, discitis, myositisInflammatory transient synovitisTrauma toddler's fractures, foot fracture, child abuse, contusions/bruisesBony deformity/problem slipped epiphysis, hip dysplasia, asceptic necrosis (legg-calve-perthes), vaso-occlusive crisis, osteochondrosis, tumors.Abdominal pain appendicitis, PID, abscessNeurologic weakness (muscular dystrophy, NMJ, GBS, TM), ataxia, infections meningitis, spinal abscess.Psychogenic - conversion

HistoryWhen was walking last normal; onset of symptoms?Any trauma?Vitals? Fever?Any LOC or abnormal movements?nausea/vertigo/posterior fossa symptoms?Why is walking altered? - pain, weakness, numbness, imbalance, can't say?

Neurologic Exam walk refusal/abnormal walkMSCN pupils, eye movements (abnormal movements, opsoclonus), CN 8 (ear exam, tinnitus, hearing loss) peripheral vestibular neuropathy/labrynthitisMotor strength weakness > myopathy/NMJ/peripheral nerve/UMNReflexes absent? -->GBS, increased?->UMNSensory uncommon reason in kids B12, tabes dorsalis, diabetic peripheral neuropathyCerebellar Rapid alternating movements (finger-tapping/alligator chomp, toe-tapping), Finger-nose-finger, heel-knee-shin, other rhythmic movements-clapping, also listen to speech.Gait romberg, tandem think of different abnormal gait types.

This lecture is on AtaxiaChildren can present with wide-based, ataxic gait OR with refusal to walk due to sense of imbalance.Static ataxia present in resting stateKinetic ataxia present only with movementDystaxiaDysmetria can't control distance/speed/power leads to past-pointingDysdiadochokinesia can't rapidly switch/alternate movements leads to poor rhythm (hand/foot tapping), leads to poor rapid alternating movements.

CerebellumMidline vermisDysarthiaTruncal titubationGait abnormalitiesHemispheresDouble-crossed tracts, ipsilateral findingsLimb dysmetriaIpsilateral veering while walkingTremorhypotonia

Abnormal GaitSpastic gaitSensory ataxic gait wide-based, high-stepping, romberg +Cerebellar ataxic gait titubation, wide-basedLMN distal weakness, foot drop, high-stepping, but narrow-basedMyopathic proximal weakness, difficulty rising from chair, Gower'sMovement disorder gaits adventitial movements, lurching gaitPsychogenic Astasia-abasia wide variation with complex movements, often wide movement off vertical axis without falling.

Romberg test-Sensory ataxia-Pt can stand with feet together with eyes open, but not eyes closed.-Cerebellar ataxia-Pt can not stand with feet together even with eyes open.-Positive romberg imbalance with eyes closed-Testing for sensory ataxia.

Causes of ataxiaACUTEBrain tumorNeuroblastomaHead-traumaVertebrobasilar dissection/strokeADEMOpsoclonus-Myoclonus-AtaxiaAcute Cerebellar AtaxiaGBSTick paralysisInfections encephalitis, cerebellar abscess, ccute labrynthitisToxicities alcohol, lead, AEDConversion reactionIntermittentBenign paroxysmal vertigoSeizureInborn Error of MetabolismBasilar migraineChronicCongenital anomaly of posterior fossaDandy-walker, chiari, cerebellar dysplasiasHereditary ataxiasFreidrich ataxia, ataxia-telangectasia, Roussy-Levy, spinocerebellar ataxia, episodic ataxiasNeurodegenerativeabetaliproteinemia, vitamin E deficiency, Refsum, Niemann-Pick,

Work-up for acute ataxiaHead imaging if AMS, focal neurologic signs, cranial neuropathies, marked asymmetric ataxia, trauma, other concerns for mass lesion posterior fossa symptoms/ elevated ICP symptomsMRI is best, especially for posterior fossa lesions, demyelinating CT if concern for hydrocephalus, trauma, mass lesions, unstableLabs UDS, alcohol level, BMP (glucose), CSF if concern for infection or GBS. Metabolic evaluation for IEM if needed

Acute Cerebellar AtaxiaAge 2-5 yoPreceded by febrile illness 4 days to 3 weeksSymptoms acute, maximal at onset gait disturbance is most common, can also have motor symptoms/fine tremor, dysarthria, 50% have nystagmusSome with vomiting and headache in older childrenShould NOT have fever, meningismus, seizure, AMS, focal neurologic signs, insiduous onsetDifferential toxic/metabolic, infectiousmeningitis, encephalitis, ADEM, labrynthitis, structural, metabolic, neurodegenerative, episodic ataxic syndrome.Work-up: CSF if fever, meningitic signs, AMS; imaging if trauma, ICP signs, posterior fossa signs, asymetric focal findings, ADEMUsually resolves within 2-3 weeks; if worsening or relapse than reconsider diagnosisTx sometimes steroids, IVIG in severe/refractory cases10% will have some long-term effects, but most recover completelyolder age and EBV associated with worse prognosis.

Opsoclonus-Myoclonus-Ataxia SyndromeDancing eyes dancing feetMean age 2 yo.Opsoclonus uncontrolled, frequent, conjugate, saccidic movement of eyes in all directions.irritability, sleep problemsAuto-immune: Paraneoplastic neuroblastoma (unknown Ab); parainfectiousDifferential: other causes of myoclonus, ataxia; toxic/metabolic dz, structuralWork-up Look for neuroblastoma CAP MRI, VMA/HVA, MIBG scan. If no neuroblastoma, then MRI brain to look for structural, toxic/metabolic, med review, infections viral (hep C, Lyme, EBV, HIV, coxsackie, rota, mycoplasma, GAS).Tx - Treat movements with immunosuppression- steroids, IVIG, rituximab.

Freidrich AtaxiaARMost common hereditary ataxia 1:50,000 CaucasianFrataxin gene 9q13 trinculeotide repeatAffects brain, heart, pancreas. Slow onset and progressive.Onset before age 25 (often by age 5), ataxia of all 4 limbs, cerebellar dysarthria, absence of LE reflexes, pyramidal signs (weakness, extensor plantars), optic atrophy, brainstem involvement (swallowing dysfunction), early loss of position/vibration without pain/temperature loss, sensineuronal hearing lossCardiomyopathy 66% of patients hypertrophic main cause of death is arrhythmia and heart failureDiabetes Mellitus 33% of patients

Ataxia-telangectasiaAR; ATM gene; 11q22.31:20-100,000ATM gene involved in detecting DNA damage, plays role in cell cycle progressionNeurologic effectsProgressive cerebellar ataxia (earliest feature; children usual begin walking, then have problems with fluid walking); articulation problemsabnormal eye movements oculmotor apraxia is earliestCan also have dystonia, chorea, peripheral axonal neuropathyOculocutaneous telangectasias oculobulbar, nose, face, ear, neck. Appear age 3-5 yo. Also can have cafe-au-lait macules.Immune deficiency recurrent sinopulmonary infectionsPulmonary disease major cause of death recurrent infections, interstitial lung disease, neuromuscular abnormalities (dysphagia, aspiration, resp muscle weakness)Malignancy 10-20% will develop cancer.

PREP QuestionA 4 year old boy presents to the emergency department with balance problems. He had been previously healthy, but his walking has worsened progressively for the past 2 days, with staggering and lurching.On PE, the boy is cooperative and alert. His muscles are not tender, and his joints are not red, swollen or tender. His vision seems functionally normal, but there is end-gaze nystagmus in all directions. When sitting independently, his head and trunk bob. His strength appears normal, and his reflexes are normal. When asked to stand with his hands outstretched, a symmetric tremor is evident, and worsens as he approaches this target on finger-to-nose testing. His gait is broad-based. A urine toxicology screen reveals normal results. Brain magnetic resonance imaging shows no tumors or other gray or white matter lesions. Lumbar puncture shows 3 WBCs, 2 RBCs, protein 20, glucose 50.

Of the following, you are MOST likely to advise the child's mother that:A. Intravenous steroids significantly reduce recurrence riskB. Neuroblastoma is a common cause of these symptomsC. Repeat lumbar puncture is needed in 2 daysD. Symptoms may resolve in weeks to monthsE. Symptoms usually resolve after antibiotic treatment

D. Symptoms may resolve in weeks to months-Cerebellar ataxia-Cerebellar findings on exam: Lateral end gaze nystagmus, dysmetria, ataxia, titubation.-Subacute onset with normal mental status suggests acute cerebellar ataxia-Usually acquired after infection or immunization-MRI shows lesion-Regarding other choices:A. Intravenous steroids significantly reduce recurrence risk: They don'tB. Neuroblastoma is a common cause of these symptoms: not as commonC. Repeat lumbar puncture is needed in 2 days: no new informationE. Symptoms usually resolve after antibiotic treatment: Not a primary infectious process

References-Uptodate articleshttp://www.studyblue.com/notes/note/n/pnb-exam-3/deck/107773http://www.medicinenet.com/image-collection/ataxia_telangiectasia_ear_picture/picture.htm-maria, b. current management in child neurology.2009-http://www.78steps.com/examination-sequence/arm-drift.html

********************