Pathophysiology Case Studies Questions and
Answers 2025-2026
AA54AyearAoldAfemaleApatientAarrivedAtoAtheAERAafterAbecomingAconfusedAandAincoherentA
toAfamilyAandAhavingAaAsyncopalAepisode.AUponAarrivalAtoAtheAERAtheApatientAwasAhypoten
siveAatA75/45,AtachycardicAatA123,AtemperatureAofA100.3AandARRAofA20.ABloodAglucoseA
wasA56.ACBCAwasAwithinAnormalAlimits.ABMPAresultsAshowedAK+A6.0AmMAandANa+A127A
mm.AFurtherAlabAtestsAshowedAcortisolAwasAdecreasedAandAACTHAwasAincreased,Acompa
redAwithAnormal.AWhichAofAtheAfollowingAisAmostAlikely?A-ACORRECTAANSWERSA-
Addison'sAdisease
TwoAweeksAafterAorthopedicAsurgery,AaA62Ayear-
oldAfemaleApresentedAwithAuncontrolledApainAandApurulentAdrainageAfromAtheAsurgicalAinci
sion.ASheAwasAadmittedAandAtakenAtoAtheAORAforAirrigationAandAdebridementAofAtheAinfecti
onAsite.AAdditionally,AsheAwasAstartedAonAantibioticsAtoAcontrolAtheAinfection.ALaterAthatAwe
ekAsheAstartedAhavingA3-
4AfoulAsmellingAwateryAstoolsAaAday,AbecameAfebrile,AandAcomplainedAofAN/V.AWhichAofAth
eAfollowingApathogensAisAmostAlikelyAcausingAherAabdominalAproblems?A-
ACORRECTAANSWERSA-C.Adiff
AA56Ayear-
oldAmaleApresentsAwithAnoAspecificAcomplaint.AHeAworksAasAaAtruckAdriverAandAhasAbeenAi
nA2AaccidentsArecentlyAandAhisAbossAinsistsAthatAheAgetsA"checkedAout"AbyAaAmedicalAprofe
ssionalAbeforeAheAcanAdriveAagain.AHeAclaimsAthatAobjectsAsuddenlyAappearAfromAoutAofAn
owhere.AHeAadmitsAtoArecentAlossAofAlibidoAandAerectileAdysfunction.AWhichAofAtheAfollowin
gAisAmostAlikely?A-ACORRECTAANSWERSA-prolactinoma
AA63Ayear-
oldAmaleApresentsAwithAdepression,Aconfusion,AvagueApainsAinAhisAbones,AandAulcers.AHeA
wasArecentlyAdiagnosedAwithAkidneyAstones.ABloodAtestsArevealAthatAPTHAisAdecreased,Aw
hileAbothAserumACa++AandAphosphateAareAincreased.AWhichAofAtheAfollowingAisAmostAlikel
y?A-ACORRECTAANSWERSA-metastaticAboneAcancer
TheAmotherAofAaA2-
yearAoldAgirlAbringsAherAdaughterAtoAtheApediatrician'sAoffice.ATheAmotherAstatesAthatAtheAp
atientAhasAhadAfrequentAwatery,AfoulAsmellingAandAsometimesAgreasyAstoolsAonAandAoffAfor
AtheApastA3Amonths.AAtAotherAtimesAsheAseemsAtoAbeAconstipated.ASheAisAnoticeablyAsmallA
forAherAageA-
AinAtheA50thApercentileAforAheightAandA25thApercentileAforAweight.ATheAmotherAalsoAreportsA
thatAafterAtheApatient'sAlastAcold,AtheAcoughAdidAnotAsubsideAforAseveralAweeksAandAeachAc
oughAwasAproducingAthick,AgrayishAmucus.AHerAmedicalArecordAshowsA3AhospitalizationsAi
nAtheApastA2AyearsAfromArespiratoryAtractAinfections,AallAofAwhichAwereAtreatedAwithAantibiot
ics.AToday,AsheAappearsAtoAbeAinAgoodAhealthAwithAnoAapparentAcough,AbutAsheAlooksAmal
nourishedAandApale.AAbdominalAultrasoundAshowedAnoAobstructionsAorAmechanicalAblock
ages,AandAstoolAcultureArevealedAnormalAbacterialAgrowth,AwithoutAviralAinfection.AStoolAsa
mpleAwasApoA-ACORRECTAANSWERSA-cysticAfibrosis
, AA2Amonth-
oldAfemaleApresentsAforAevaluationAofApoorAfeeding.ASheAisAinAnoAapparentAacuteAdistress,A
butAmomAreportsAthatAsheAhasAdifficultyAwithAfeedingAandAgetAshortAofAbreathAatAtimes.AMo
mAisAconcernedAthatAtheAbabyAseemsAtoAbeAlosingAweightAandAisAexcessivelyAtired.ATheAba
by'sAweightAisAbelowAaverageAforAageAandAlength.ASheAisAalertAatAthisAtimeAandAdoesAnotAa
ppearAtoAbeAinAanyAacuteAdistress.ARespiratoryArateAisA41,AandAauscultationArevealsAcrackl
esAinAbilateralAbases.APatientAisAafebrileAandAhasAstrongAperipheralApulsesAinAupperAandAlo
werAextremities.AAuscultationArevealsAaAHRAofA140AwithAaAcontinuousAmurmur.AWhichAsce
narioAisAmostAlikelyAinAthisApatient?A-ACORRECTAANSWERSA-patentAductusAateriosus
AA72AyearAoldAmaleApresentsAtoAtheAEDAcomatose.AVitalsAareAHRA132A(SinusATachycardia
),ABPA87/45.ACMPAshowsAbloodAglucoseA2250A(mg/dl),ApHA7.41,ANa+A133,AK+A4.6,ACl-
A97,AHCO3-
A23,AandAserumAosmolarityA356AmOsm.AWhichAscenarioAisAmostAlikelyAinAthisApatient?A-
ACORRECTAANSWERSA-hyperosmolarAhyperglycemicAnon-ketoticAsyndrome
OneAweekAafterAaAsevereAstrepAthroat,AaA6AyearAoldAfemaleApatientApresentsAwithAoliguria.A
WhichAtypeAofAglomerularAnephritisAisAmostAlikelyAinAthisApatient?A-
ACORRECTAANSWERSA-acuteAproliferativeA(postinfectious)Aglomerulonephritis
AA34Ay/oAfemaleApresentsAtoAtheAEDAwithAanxiety,Apalpitations,AandAchestApain.ASheAisAcur
rentlyAreceivingAradiationAtoAtheAchestAasAaAresultAofAbreastAcancer.ASheAdeniesAfever,Achill
s,ASOB,Acough,AabdominalApain,AorAN/V/D.AVitalAsignsAare:ATA98.9,ABPA90/60,AHRA100,AR
RA26,ASpO2A98%ARA.ALungsAareAclearAtoAauscultationAbilaterally.AHeartAshowsAregularArh
ythmAwithAweakAS1,AS2,AandAfaintArub.AJugularAvenousAdistensionAisApresent.APeripheralAp
ulsesAareAweakAbilaterally.AEKGAshowsAnormalAsinusArhythmAwithAdecreasedAvoltage.ACh
estAx-
rayAshowsAincreasedAcardiacAsilhouette.AEchocardiogramAisApositiveAforAeffusion.AWhichA
scenarioAisAmostAlikelyAinAthisApatient?A-ACORRECTAANSWERSA-cardiacAtamponade
AA23Ayear-
oldAmaleApresentedAtoAtheAEDAwithAcomplaintsAofAchestApainAofA19AmonthsAduration.AChes
tApainAwasAaggravatedAbyAstrenuousAactivitiesAandAmoderatelyArelievedAwithArest.APatientA
statedAaAhistoryAofAdyspneaAonAexertionAandAeffortAintoleranceAsinceAchildhood.APatientAre
memberedAfrequentAsquattingAtoArelieveAepisodesAofAbreathlessnessAfollowingAexertion.A
PatientAdeniesAhistoryAofAcough,AchangeAinAurineAorAbowels,AlegAswelling,AnocturiaAorAolig
uria.AGeneralAexaminationAshowedAcentralAcyanosisAwithAdigitalAclubbing.APulseAwasAregu
larAwithAaArateAofA80ABPM,AandABPAwasA120/70AmmHg.ACardiacAexaminationAfoundAaAsyst
olicAmurmur.ATheAlungsAwereAclearAandAabdomenAwasAnon-
tender.AChestAradiographAshowedAenlargedAheartAwithApulmonaryAoligemiaAwithArightAvent
ricularAhypertrophy.AThereAwasAnoAaorticAorAmitralAregurgitation.APatientAHctAwasA72%.AW
hichAscenarioAisAmostAlikelyAinAthisApatient?A-ACORRECTAANSWERSA-TetralogyAofAFallot
AA3AyearAoldApresentsAtoAtheAERAwithAacuteAleftAsidedAfacialApalsy.APatient'sAmotherAstates
AherAsonAhasAbeenAirritableAoverAtheAlastAfewAweeks.AHisAcurrentAVSAinclude:A36.6Adegree
sAC,AHRA80AbpmAinAsinusArhythm,ABPA180/110,ARRA22,AandAoxygenAsaturationAofA99%AonA
RA.AOnAassessment,ApatientAhasAaAnormalAneurologicAexamAexceptAforAhisAleftAsidedAfaci
alApalsy.AHeAhasAnoAcardiacAmurmurAandAhasA2+ApulsesAonAbothAupperAandAlowerAextremi
ties.AHisAlungsAareAclearAtoAauscultation.APatientAisAplacedAonAaAcardiacAmonitor,AwhichAco
ntinuesAtoAshowAaAnormalAHRAandArhythm.AAACTAscanAisAnegativeAforAaAcranialAbleed.AThe
AfollowingAlabsAareAallAnormal:ACBC,AserumAelectrolytes,ABUN,Acreatinine,AurinalysisAandA
Answers 2025-2026
AA54AyearAoldAfemaleApatientAarrivedAtoAtheAERAafterAbecomingAconfusedAandAincoherentA
toAfamilyAandAhavingAaAsyncopalAepisode.AUponAarrivalAtoAtheAERAtheApatientAwasAhypoten
siveAatA75/45,AtachycardicAatA123,AtemperatureAofA100.3AandARRAofA20.ABloodAglucoseA
wasA56.ACBCAwasAwithinAnormalAlimits.ABMPAresultsAshowedAK+A6.0AmMAandANa+A127A
mm.AFurtherAlabAtestsAshowedAcortisolAwasAdecreasedAandAACTHAwasAincreased,Acompa
redAwithAnormal.AWhichAofAtheAfollowingAisAmostAlikely?A-ACORRECTAANSWERSA-
Addison'sAdisease
TwoAweeksAafterAorthopedicAsurgery,AaA62Ayear-
oldAfemaleApresentedAwithAuncontrolledApainAandApurulentAdrainageAfromAtheAsurgicalAinci
sion.ASheAwasAadmittedAandAtakenAtoAtheAORAforAirrigationAandAdebridementAofAtheAinfecti
onAsite.AAdditionally,AsheAwasAstartedAonAantibioticsAtoAcontrolAtheAinfection.ALaterAthatAwe
ekAsheAstartedAhavingA3-
4AfoulAsmellingAwateryAstoolsAaAday,AbecameAfebrile,AandAcomplainedAofAN/V.AWhichAofAth
eAfollowingApathogensAisAmostAlikelyAcausingAherAabdominalAproblems?A-
ACORRECTAANSWERSA-C.Adiff
AA56Ayear-
oldAmaleApresentsAwithAnoAspecificAcomplaint.AHeAworksAasAaAtruckAdriverAandAhasAbeenAi
nA2AaccidentsArecentlyAandAhisAbossAinsistsAthatAheAgetsA"checkedAout"AbyAaAmedicalAprofe
ssionalAbeforeAheAcanAdriveAagain.AHeAclaimsAthatAobjectsAsuddenlyAappearAfromAoutAofAn
owhere.AHeAadmitsAtoArecentAlossAofAlibidoAandAerectileAdysfunction.AWhichAofAtheAfollowin
gAisAmostAlikely?A-ACORRECTAANSWERSA-prolactinoma
AA63Ayear-
oldAmaleApresentsAwithAdepression,Aconfusion,AvagueApainsAinAhisAbones,AandAulcers.AHeA
wasArecentlyAdiagnosedAwithAkidneyAstones.ABloodAtestsArevealAthatAPTHAisAdecreased,Aw
hileAbothAserumACa++AandAphosphateAareAincreased.AWhichAofAtheAfollowingAisAmostAlikel
y?A-ACORRECTAANSWERSA-metastaticAboneAcancer
TheAmotherAofAaA2-
yearAoldAgirlAbringsAherAdaughterAtoAtheApediatrician'sAoffice.ATheAmotherAstatesAthatAtheAp
atientAhasAhadAfrequentAwatery,AfoulAsmellingAandAsometimesAgreasyAstoolsAonAandAoffAfor
AtheApastA3Amonths.AAtAotherAtimesAsheAseemsAtoAbeAconstipated.ASheAisAnoticeablyAsmallA
forAherAageA-
AinAtheA50thApercentileAforAheightAandA25thApercentileAforAweight.ATheAmotherAalsoAreportsA
thatAafterAtheApatient'sAlastAcold,AtheAcoughAdidAnotAsubsideAforAseveralAweeksAandAeachAc
oughAwasAproducingAthick,AgrayishAmucus.AHerAmedicalArecordAshowsA3AhospitalizationsAi
nAtheApastA2AyearsAfromArespiratoryAtractAinfections,AallAofAwhichAwereAtreatedAwithAantibiot
ics.AToday,AsheAappearsAtoAbeAinAgoodAhealthAwithAnoAapparentAcough,AbutAsheAlooksAmal
nourishedAandApale.AAbdominalAultrasoundAshowedAnoAobstructionsAorAmechanicalAblock
ages,AandAstoolAcultureArevealedAnormalAbacterialAgrowth,AwithoutAviralAinfection.AStoolAsa
mpleAwasApoA-ACORRECTAANSWERSA-cysticAfibrosis
, AA2Amonth-
oldAfemaleApresentsAforAevaluationAofApoorAfeeding.ASheAisAinAnoAapparentAacuteAdistress,A
butAmomAreportsAthatAsheAhasAdifficultyAwithAfeedingAandAgetAshortAofAbreathAatAtimes.AMo
mAisAconcernedAthatAtheAbabyAseemsAtoAbeAlosingAweightAandAisAexcessivelyAtired.ATheAba
by'sAweightAisAbelowAaverageAforAageAandAlength.ASheAisAalertAatAthisAtimeAandAdoesAnotAa
ppearAtoAbeAinAanyAacuteAdistress.ARespiratoryArateAisA41,AandAauscultationArevealsAcrackl
esAinAbilateralAbases.APatientAisAafebrileAandAhasAstrongAperipheralApulsesAinAupperAandAlo
werAextremities.AAuscultationArevealsAaAHRAofA140AwithAaAcontinuousAmurmur.AWhichAsce
narioAisAmostAlikelyAinAthisApatient?A-ACORRECTAANSWERSA-patentAductusAateriosus
AA72AyearAoldAmaleApresentsAtoAtheAEDAcomatose.AVitalsAareAHRA132A(SinusATachycardia
),ABPA87/45.ACMPAshowsAbloodAglucoseA2250A(mg/dl),ApHA7.41,ANa+A133,AK+A4.6,ACl-
A97,AHCO3-
A23,AandAserumAosmolarityA356AmOsm.AWhichAscenarioAisAmostAlikelyAinAthisApatient?A-
ACORRECTAANSWERSA-hyperosmolarAhyperglycemicAnon-ketoticAsyndrome
OneAweekAafterAaAsevereAstrepAthroat,AaA6AyearAoldAfemaleApatientApresentsAwithAoliguria.A
WhichAtypeAofAglomerularAnephritisAisAmostAlikelyAinAthisApatient?A-
ACORRECTAANSWERSA-acuteAproliferativeA(postinfectious)Aglomerulonephritis
AA34Ay/oAfemaleApresentsAtoAtheAEDAwithAanxiety,Apalpitations,AandAchestApain.ASheAisAcur
rentlyAreceivingAradiationAtoAtheAchestAasAaAresultAofAbreastAcancer.ASheAdeniesAfever,Achill
s,ASOB,Acough,AabdominalApain,AorAN/V/D.AVitalAsignsAare:ATA98.9,ABPA90/60,AHRA100,AR
RA26,ASpO2A98%ARA.ALungsAareAclearAtoAauscultationAbilaterally.AHeartAshowsAregularArh
ythmAwithAweakAS1,AS2,AandAfaintArub.AJugularAvenousAdistensionAisApresent.APeripheralAp
ulsesAareAweakAbilaterally.AEKGAshowsAnormalAsinusArhythmAwithAdecreasedAvoltage.ACh
estAx-
rayAshowsAincreasedAcardiacAsilhouette.AEchocardiogramAisApositiveAforAeffusion.AWhichA
scenarioAisAmostAlikelyAinAthisApatient?A-ACORRECTAANSWERSA-cardiacAtamponade
AA23Ayear-
oldAmaleApresentedAtoAtheAEDAwithAcomplaintsAofAchestApainAofA19AmonthsAduration.AChes
tApainAwasAaggravatedAbyAstrenuousAactivitiesAandAmoderatelyArelievedAwithArest.APatientA
statedAaAhistoryAofAdyspneaAonAexertionAandAeffortAintoleranceAsinceAchildhood.APatientAre
memberedAfrequentAsquattingAtoArelieveAepisodesAofAbreathlessnessAfollowingAexertion.A
PatientAdeniesAhistoryAofAcough,AchangeAinAurineAorAbowels,AlegAswelling,AnocturiaAorAolig
uria.AGeneralAexaminationAshowedAcentralAcyanosisAwithAdigitalAclubbing.APulseAwasAregu
larAwithAaArateAofA80ABPM,AandABPAwasA120/70AmmHg.ACardiacAexaminationAfoundAaAsyst
olicAmurmur.ATheAlungsAwereAclearAandAabdomenAwasAnon-
tender.AChestAradiographAshowedAenlargedAheartAwithApulmonaryAoligemiaAwithArightAvent
ricularAhypertrophy.AThereAwasAnoAaorticAorAmitralAregurgitation.APatientAHctAwasA72%.AW
hichAscenarioAisAmostAlikelyAinAthisApatient?A-ACORRECTAANSWERSA-TetralogyAofAFallot
AA3AyearAoldApresentsAtoAtheAERAwithAacuteAleftAsidedAfacialApalsy.APatient'sAmotherAstates
AherAsonAhasAbeenAirritableAoverAtheAlastAfewAweeks.AHisAcurrentAVSAinclude:A36.6Adegree
sAC,AHRA80AbpmAinAsinusArhythm,ABPA180/110,ARRA22,AandAoxygenAsaturationAofA99%AonA
RA.AOnAassessment,ApatientAhasAaAnormalAneurologicAexamAexceptAforAhisAleftAsidedAfaci
alApalsy.AHeAhasAnoAcardiacAmurmurAandAhasA2+ApulsesAonAbothAupperAandAlowerAextremi
ties.AHisAlungsAareAclearAtoAauscultation.APatientAisAplacedAonAaAcardiacAmonitor,AwhichAco
ntinuesAtoAshowAaAnormalAHRAandArhythm.AAACTAscanAisAnegativeAforAaAcranialAbleed.AThe
AfollowingAlabsAareAallAnormal:ACBC,AserumAelectrolytes,ABUN,Acreatinine,AurinalysisAandA