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Decreased mental status and central D emyelinating emergencies. Bradley Osterman Pediatric neurology – R4 Summer lecture series 2012. Plan. Introduction C onsciousness & impaired consciousness Coma Etiologies of coma DD of coma-like states Demyelinating emergencies ADEM
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Decreased mental status and central Demyelinating emergencies Bradley Osterman Pediatricneurology– R4 Summer lecture series 2012
Plan • Introduction • Consciousness & impairedconsciousness • Coma • Etiologies of coma • DD of coma-like states • Demyelinating emergencies • ADEM • NMO • Demyelinating w/u of a CIE
Introduction • Patientbroughtinto the ER unconscious • First reflex • The « ABC » • But don’tforget about the « D » ! • Disability
Consciousness • Whatdoesitmean to a neurologist? • Product of two basic brainfunctions • (1) Arousal –wakefulness • ARAS (ascendingreticularactivating system) • (2) Awareness • encompasses multiple functions - attention, memory & executivefunction • Impairedconsciousnesscanresultfromderangement in : • (1) arousal, • (2) awareness, • (3) or both, in varyingdegress
Impairedconsciousness • There is a widespectrum • Avoidconfusing, imprecisetermssuch as : • Somnolence, stupor, obtundation, lethargy • Use specificstatements to describe the patient’s LOC: • Ex. « patient responds to painful sternal rub by grimacing & moving R arm »
Glascow coma scale Has its limitations. Originallydesigned for TBI GCS 12-14 – mildalteration of consciousness GCS 9-11 – moderate GCS 8 and below – severe
Coma • The term « coma » isactually a specific state of consciousnesscharacterizedby : • Acomplete absence of both (1) arousal & (2) awareness • For ≥ 1 hour • Absence of normal sleep-wakecycle • No spontaneous or stimulus-inducedeye-opening • No purposefulmvts • Be familiarwith the DD of coma-like conditions
Etiologies of coma • (1) Direct insult to the CNS • Structural causes • Supratentorial (ie. Braintumor, hemorrage, encephalitis) • Subtentorial (ie. Midbraininfarction, acute demyelination of brainstem ) • Seizures (NC SE) • Hydrocephalus/raised ICP • Traumaticbraininjury (TBI) • (2) Metabolic/toxic causes
Locked-in syndrome • Occurswithbrainstem injuries sparing the midbrain • Patients have normal (1) arousal & mostly intact (2) awareness, • but have a severelylimitedability to communicate • due to paralysis of voluntary muscles & anarthria • Can beseenwith : • Pontineglioma • Basilarartery occlusion • Profoundneuromusculardysfunction (GBS, SMA, botulism, organophosphatetoxicity) • Trauma
Akineticmutism • State of profoundapathywithpartiallyintact awareness, and paucity and slowness of voluntarymvts • (1) Normal arousal, and (2) mostly intact awareness (normal attentive pursuit) • On the verge of initiating speech or motoractivity (but neverhappens) • Seenwithbilateral injuries to the midbrain, basal diencephalon, or inferior frontal lobes, occuring in : • Tumors or tumorresection (mainlyposteriorfossa) • TBI • Hydrocephalus • CNS infections
Minimallyconscious state • Relatively new term • (1) Arousal present & (2) minimallypresentawareness • Patients capable of reproducible & purposeful (albeitverylimited) motormovements or affective behaviour • Ex. following simple commands, • reachingaccurately for an object, • crying or smiling in response to emotional stimuli
Vegetative state • Arousal present • Awareness absent (self & environment) • No voluntary or purposefulmvts • Preservedrespiratoryfunction & sleep-wake cycles • Includingperiods of spontaneouseye-opening • Intactbrainstem & hypothalamicfunction • Considered permanent if lasts : • > 12 monthsafter TBI or • > 3 monthsafternon-traumaticbraininjury
Braindeath • Complete & irreversibleloss of (1) brain and (2) brainstemfunction, characterized by : • Loss of consciousness • Loss of cranial nerve function • Loss of motorfunction • Loss of breathingactivity • Loss of sleep-wake cycle • Specificcriteria–completebraindeath exam
ADEM (acute disseminatedencephalomyelitis) • An autoimmune-mediatedinflammatoryepisodeinvolving the CNS • Usuallymonophasic (5-20% cases are multi-phasic) • Usuallyfollowing an infection (or vaccination; 3-6% of cases) • Up to 4 weeksprior to sx (gen. 1-20 days) • Children> adults (peakages 5-8 y/o) • Incidence 8/1,000,000; seasonalincrease in spring & wintermonths • Describedequally in all racial, ethnic groups and genders (unlike MS) • Mortality rate – 5% • Full recovery – 50-75% • Averagetime to recovery – 6 months
ADEM –clinicalpresentation • Abrupt onset • Withrapid progression – maximum deficits < 1 week (average 4.5 days) • Encephalopathy • Mild to severealteration in mental status (irritability to coma) • Convulsive seizures (25%) • Focal neuroaN • Weakness, ataxia, visualaN, sensoryaN, cranial nerve aN, sphincter dysfunstion • Constitutionalsx • H/A, No/Vo, malaise
ADEM –physical exam • Alteration in mental status (>90%) • Cranial nerve aN (35-50%) (w/ possible brainstemdysfunction) • Meningealsigns (20%) • Weakness (50-75%) • Hemiparesis, diaparetic, generalized • Long tract signs (80%) • Clonus, increased DTR, upgoingtoes • Ataxia (35-60%) • Sensorydeficits (15-20%) (w/ possible sensorylevel)
ADEM – MRI • ADEM – axial T2-weighted images • Large, T2-hyperintense, patchy, poorlycircumscribed
ADEM – MRI • ADEM – sagittal cervical spine & axial T2-weighted brain images • Large, T2-hyperintense, patchy, poorlycircumscribed
ADEM – MRI • Typicallyinvolves the gray-whitejunction • ADC map– consistent w/ vasogenicedema • Gado-enhancing (30-90%) • Compared to MS • Periventricularlesions (30-45%) and corpus callosumlesions (20-25%) are lesscommon in ADEM • Additionallesionsfound in: • opticnerves, basal ganglia (30-40%), the thalamus (30-40%), the brainstem (45-55%), the cerebellum (30-40%) & spinal cord
ADEM – Investigations • Lumbarpuncture • leukocytosis (80%); N/elevated OP, proteinoften > 1.0; N glucose; absent OCB • CSF cultures, serologiestypicallynegative • EEG – diffuse slowing • Work-up for otherDemyelinatingdisorders & Mimics
ADEM –treatment • 1st line tx – high-dose IV corticosteroids • Methylprednisolone (Solumedrol) – 30 mg/kg/day x 5 days • Up to max 1 G Solumedroldaily x 5 days (ie. Like in adults) • Followed by 3-6 weeks of taperingprednisone • Lessthan 3 week taper has a higherrisk of relapse • 2ndline – IVIG • and/or plasma exchangev(PLEX)
ADEM –evolution/classification • Monophasic (same acute episode) • Withfluctuating/subsequentsx as long as the relapse is : • < 3 months of onset • < 1 monthfollowingsteroidtx • Recurrent ADEM • Relapse withidenticalsx • ≥ 3 months or ≥ 1 monthfollowingsteroidtx • Multi-Phasic • Relapse with new features and change in mental status • ≥ 3 months or ≥ 1 month of steroidtx • MRI must show new areas of involvement & partial resolution of previouslesions
NMO –neuromyelitisoptica • NMO or Devic’sdisease • Idiopathic, inflammatory, necrotizingdemyelination of the CNS • Simultaneous or successive involvement of : • optic nerves & spinal cord • Mediated by anti-NMO-IgGantibodies • Unlike MS, not T-cellmediated • Targets the proteinaquaporin 4 in the cell membrane of astrocytes • Impaired water transport across the membrane leading to inflammatorydemyelination
NMO –clinicalpresentation • Visualloss (painful & subacute) • Opticneuritis (ON) • Spinalcorddysfunction • Transverse myelitis (TM) • weakness • sensorydeficits (w/ level) • sphincter dysfunction • Unilateral ON (45%); simultaneous & bilateral ON (25-30%) • Isolated TM (10-15%) • Simultaneous ON & TM (10-15%)
NMO –treatment • High-doseglucocorticodtherapy • IVIG/PLEX • Obtainsample for anti-NMO ab prior • Immunosuppressanttherapy • Ex. Imuran
NMO –prognosis • High rate of recurrence (> 90%) • Relapse within first year (50%), and within 5 years (90%) • Relapseintervalgenerally < 3 months • Deficits (ON/TM) tend to besevere & recoveryincomplete • Permanentlegparalysis and/or blindness in > 50%
Demyelinating (CIS) work-up–at MCH • Serum • CBC, Glucose, Lactate, TSH, T4, vit B12, IgG index, VLCFA • ESR, CRP, ANA, dsDNA, APLA, ACE (vasculitic w/u) • Viral serologies (HIV, VDRL, HSV) • Lyme (serology +/- PCR) • CSF • Cell count (WBC), Glucose, Protein, Lactate (on ice) • OCB (w/ serumIgG index) • Viral culture (enterovirus, CMV), Bacterial culture • Herpes PCR, Mycoplasma PCR