CERTIFIED MULTIPLE SCLEROSIS SPECIALIST EXAM PREP
(CMSC) | COMPLETE SOLUTIONS |2026 NEWEST
UPDATE!!!!!!!!!!
Pathophysiology:vImmunevDysfunctionv-
vcorrectvanswer:vvAnvimpairmentvofvimmunevtolerancevtovcentralvnervousvsystemvtissuevthatvultimatelyvle
adsvtovplaquevformation.
Thevmostvwidelyvbelievedvhypothesisvisvthatvitvisvavvirus-inducedvimmune-mediatedvdisease.
UnusuallyvhighvreactivityvofvimmunevsystemvTvcellsvtovproteinsvofvmyelinvinvthevCNS
Overrepresentationvofvcellsvthatvenhancevimmunevresponsesv(pro-inflammatoryvTvhelpervcells)
PresencevofvimmunevsystemvcellsvinvMSvlesionsvinvthevbrain,vspinalvcord,vandvopticvnerves
Bvlymphocytesvresponsiblevforvproducingvantibodies
Pathophysiology:v
DestructionvofvMyelinvandvAxonalvDamagevorvLossv-
vcorrectvanswer:vvPathologyvofvMSvconsistsvofvlesionsvdisseminatedvinvlocationvandvofvvaryingvage.v
Lesionsvarevpresentvinvbothvwhitevandvgrayvmatter,vgrayvmattervlesionsvarevlessvevident.
Oligodendrocytesvarevdamagedvinvthisvprocess.
Lesionsvrangevfromvacutevplaquesvwithvactivevinflammatoryvinfiltratesvtovchronic,vinactive,vdemyelinatedv
scars.
Slowedvconductionvandvconductionvfailurevoccurvinvdemyelinatedvfibers.vConductionvfailurevisvduevtovfibe
rvfatiguevorvtovanvincreasevinvbodyvtemperature.
Ongoingvinflammation,vdemyelination,vandvscarringvultimatelyvresultvinvirreversiblevaxonalvdamagevandvl
oss.
AcutevMSvlesionsvarevcharacterizedvbyvTvlymphocytes,vplasmavcells,vmacrophages,vandvbare,vdemyelinate
d,vorvtransectedvaxons.
BrainvatrophyvinvMSvrepresentsvavnegativevpathologicvchange.
,TheoriesvofvEtiology:vGeneticsv-
vcorrectvanswer:vvIncreasedvsusceptibilityvisvpresentvinvfamiliesvinvwhichvMSvalreadyvoccurs
Highvgeneticvsusceptibilityvobservedvinvmonozygoticvtwinsv(20%-40%)
SomevgeneticallyvisolatedvgroupsvnevervdevelopvMSv(HutteritesvinvCanada,vEast-EuropeanvGypsies)v
RacialvdifferencesvinvMSvarevlikelyvgeneticallyvbased
TheoriesvofvEtiology:vEnvironmentalv-vcorrectvanswer:vv
TheoriesvofvEtiology:vOtherv-vcorrectvanswer:vv
Epidemiology:vGeographicvDistributionv-
vcorrectvanswer:vvHighvRiskv(>v30vperv100,000):vnorthernvandvcentralvEurope,vItaly,vnorthernvUnitedvState
s,vCanada,vsouthesternvAustralia,vNewvZealand,vpartsvofvformervSovietvUnion
MediumvRiskv(5-
29vperv100,000):vsouthernvEurope,vsouthernvUnitedvStates,vnorthernvAustralia,vnorthernmostvScandinavi
a,vmuchvofvthevnorthvMediterraneanvbasin,vpartsvofvformervSovietvUnion,vwhitevSouthvAfrica,vcentralvSou
thvAmerica
LowvRiskv(<v5vperv100,000):vAfrica,vAsia,vthevCaribbean,vMexico,vnorthernvSouthvAmerica
InvthevUSvstatesvsouthvofvthev37thvparallelvhavevavlowervriskvthanvthosevnorthvofvthevparallel
Peoplevwhovresidevinvtemperatevclimatesvinveconomicallyvdevelopedvwesternvcountriesvtendvtovhavevhig
hervratevofvMS
Thosevoldervthanv15vwhovmigratevretainvthevMSvriskvofvtheirvbirthplace.vThosevmigratingvbeforevagev15va
quirevthevlowervriskvofvthevnewvresidence
Epidemiology:vGenderv-vcorrectvanswer:vvFemalesvhavev3>1vgreatervriskvofvdevelopingvMSv(70-75%)
PPMSv=v50/50
Epidemiology:vAgevofvOnsetv-vcorrectvanswer:vv10-59vyears,vhighestvincidencevbetweenv20-40vyears
, Averagevagevofvonsetvisv28-30vyears
Epidemiology:vEthnicityv-vcorrectvanswer:vvHighestvprevalence:vWhite/Caucasianv
Lowestvprevalence:vJapanese
Asiansvarevmorevlikelyvtovhavevspinalvcordopticvnervevdiseasev(oldervagevonset,vfewervbrainvlesions,vmore
venhancingvlesionsvinvspinalvcord)
DiagnosisvofvMultiplevSclerosis:v
DiagnosticvCriteriav-
vcorrectvanswer:vvMSvisvavclinicalvdiagnosisvbecausevnovdefinitivevlaboratoryvtestvexists.
DiagnosisvofvMSvisvbasedvuponvtwovepisodesvofvneurologicvsymptomsvreferablevtovthevCNSvseparatedvinvs
pacev(differentvlocationvinvthevCNS),vandvtimev(differentvpointvinvtimevforveachvevent).v
ThevrevisedvMcDonaldvcriteriavforvdisseminationvinvtimevarevdetectionvofvGdvenhancementvatvleastv3vmo
nthsvaftervthevonsetvofvthevfirstvclinicalveventvorvdetectionvofvavnewvT2vlesionvappearingvatvanyvtimevcom
paredvwithvavreferencevscanvdonevatvleastv30vdaysvaftervthevonsetvofvthevinitialvclinicalvevent.
RevisedvMcDonaldvcriteria:
1.vTwovattacksvofvdiseasevseparatedvinvspacevandvtime
2.vMustvbevnovbettervexplanation
3.vThreevpossiblevoutcomes:vMultiplevSclerosis,vPossiblevMS,vNotvMS
4.vMonosymptomaticvpresentation:vOnevattack,vOnevobjectivevclinicalvlesion,vMRIvevidence
5.vPrimaryvProgressivevMS:vPositivevCSFvandvdisseminationvinvspace,vMRIvevidencevalongvwithvevokedvpo
tentialsvandvCSF,vContinuedvprogressionvoverv1vyear
6.vDiagnosisvshouldvalwaysvbevmadevinvthevclinicalvcontext
7.vParaclinicalvevidencevalongvwithvMRIvincludesvcerebrospinalvfluidvwithvIgGvoligoclonalvbands
DiagnosisvofvMultiplevSclerosis:v
PresentingvClinicalvSymptomsv-
vcorrectvanswer:vvSymptomaticvdiseasevmeansvneurologicvworseningvinvhevformvofvepisodicvattacksvorvslo
wvprogression.
Thevmostvcommonvpresentationsvarevasvfollows:
(CMSC) | COMPLETE SOLUTIONS |2026 NEWEST
UPDATE!!!!!!!!!!
Pathophysiology:vImmunevDysfunctionv-
vcorrectvanswer:vvAnvimpairmentvofvimmunevtolerancevtovcentralvnervousvsystemvtissuevthatvultimatelyvle
adsvtovplaquevformation.
Thevmostvwidelyvbelievedvhypothesisvisvthatvitvisvavvirus-inducedvimmune-mediatedvdisease.
UnusuallyvhighvreactivityvofvimmunevsystemvTvcellsvtovproteinsvofvmyelinvinvthevCNS
Overrepresentationvofvcellsvthatvenhancevimmunevresponsesv(pro-inflammatoryvTvhelpervcells)
PresencevofvimmunevsystemvcellsvinvMSvlesionsvinvthevbrain,vspinalvcord,vandvopticvnerves
Bvlymphocytesvresponsiblevforvproducingvantibodies
Pathophysiology:v
DestructionvofvMyelinvandvAxonalvDamagevorvLossv-
vcorrectvanswer:vvPathologyvofvMSvconsistsvofvlesionsvdisseminatedvinvlocationvandvofvvaryingvage.v
Lesionsvarevpresentvinvbothvwhitevandvgrayvmatter,vgrayvmattervlesionsvarevlessvevident.
Oligodendrocytesvarevdamagedvinvthisvprocess.
Lesionsvrangevfromvacutevplaquesvwithvactivevinflammatoryvinfiltratesvtovchronic,vinactive,vdemyelinatedv
scars.
Slowedvconductionvandvconductionvfailurevoccurvinvdemyelinatedvfibers.vConductionvfailurevisvduevtovfibe
rvfatiguevorvtovanvincreasevinvbodyvtemperature.
Ongoingvinflammation,vdemyelination,vandvscarringvultimatelyvresultvinvirreversiblevaxonalvdamagevandvl
oss.
AcutevMSvlesionsvarevcharacterizedvbyvTvlymphocytes,vplasmavcells,vmacrophages,vandvbare,vdemyelinate
d,vorvtransectedvaxons.
BrainvatrophyvinvMSvrepresentsvavnegativevpathologicvchange.
,TheoriesvofvEtiology:vGeneticsv-
vcorrectvanswer:vvIncreasedvsusceptibilityvisvpresentvinvfamiliesvinvwhichvMSvalreadyvoccurs
Highvgeneticvsusceptibilityvobservedvinvmonozygoticvtwinsv(20%-40%)
SomevgeneticallyvisolatedvgroupsvnevervdevelopvMSv(HutteritesvinvCanada,vEast-EuropeanvGypsies)v
RacialvdifferencesvinvMSvarevlikelyvgeneticallyvbased
TheoriesvofvEtiology:vEnvironmentalv-vcorrectvanswer:vv
TheoriesvofvEtiology:vOtherv-vcorrectvanswer:vv
Epidemiology:vGeographicvDistributionv-
vcorrectvanswer:vvHighvRiskv(>v30vperv100,000):vnorthernvandvcentralvEurope,vItaly,vnorthernvUnitedvState
s,vCanada,vsouthesternvAustralia,vNewvZealand,vpartsvofvformervSovietvUnion
MediumvRiskv(5-
29vperv100,000):vsouthernvEurope,vsouthernvUnitedvStates,vnorthernvAustralia,vnorthernmostvScandinavi
a,vmuchvofvthevnorthvMediterraneanvbasin,vpartsvofvformervSovietvUnion,vwhitevSouthvAfrica,vcentralvSou
thvAmerica
LowvRiskv(<v5vperv100,000):vAfrica,vAsia,vthevCaribbean,vMexico,vnorthernvSouthvAmerica
InvthevUSvstatesvsouthvofvthev37thvparallelvhavevavlowervriskvthanvthosevnorthvofvthevparallel
Peoplevwhovresidevinvtemperatevclimatesvinveconomicallyvdevelopedvwesternvcountriesvtendvtovhavevhig
hervratevofvMS
Thosevoldervthanv15vwhovmigratevretainvthevMSvriskvofvtheirvbirthplace.vThosevmigratingvbeforevagev15va
quirevthevlowervriskvofvthevnewvresidence
Epidemiology:vGenderv-vcorrectvanswer:vvFemalesvhavev3>1vgreatervriskvofvdevelopingvMSv(70-75%)
PPMSv=v50/50
Epidemiology:vAgevofvOnsetv-vcorrectvanswer:vv10-59vyears,vhighestvincidencevbetweenv20-40vyears
, Averagevagevofvonsetvisv28-30vyears
Epidemiology:vEthnicityv-vcorrectvanswer:vvHighestvprevalence:vWhite/Caucasianv
Lowestvprevalence:vJapanese
Asiansvarevmorevlikelyvtovhavevspinalvcordopticvnervevdiseasev(oldervagevonset,vfewervbrainvlesions,vmore
venhancingvlesionsvinvspinalvcord)
DiagnosisvofvMultiplevSclerosis:v
DiagnosticvCriteriav-
vcorrectvanswer:vvMSvisvavclinicalvdiagnosisvbecausevnovdefinitivevlaboratoryvtestvexists.
DiagnosisvofvMSvisvbasedvuponvtwovepisodesvofvneurologicvsymptomsvreferablevtovthevCNSvseparatedvinvs
pacev(differentvlocationvinvthevCNS),vandvtimev(differentvpointvinvtimevforveachvevent).v
ThevrevisedvMcDonaldvcriteriavforvdisseminationvinvtimevarevdetectionvofvGdvenhancementvatvleastv3vmo
nthsvaftervthevonsetvofvthevfirstvclinicalveventvorvdetectionvofvavnewvT2vlesionvappearingvatvanyvtimevcom
paredvwithvavreferencevscanvdonevatvleastv30vdaysvaftervthevonsetvofvthevinitialvclinicalvevent.
RevisedvMcDonaldvcriteria:
1.vTwovattacksvofvdiseasevseparatedvinvspacevandvtime
2.vMustvbevnovbettervexplanation
3.vThreevpossiblevoutcomes:vMultiplevSclerosis,vPossiblevMS,vNotvMS
4.vMonosymptomaticvpresentation:vOnevattack,vOnevobjectivevclinicalvlesion,vMRIvevidence
5.vPrimaryvProgressivevMS:vPositivevCSFvandvdisseminationvinvspace,vMRIvevidencevalongvwithvevokedvpo
tentialsvandvCSF,vContinuedvprogressionvoverv1vyear
6.vDiagnosisvshouldvalwaysvbevmadevinvthevclinicalvcontext
7.vParaclinicalvevidencevalongvwithvMRIvincludesvcerebrospinalvfluidvwithvIgGvoligoclonalvbands
DiagnosisvofvMultiplevSclerosis:v
PresentingvClinicalvSymptomsv-
vcorrectvanswer:vvSymptomaticvdiseasevmeansvneurologicvworseningvinvhevformvofvepisodicvattacksvorvslo
wvprogression.
Thevmostvcommonvpresentationsvarevasvfollows:
