MICROBIOLOGY CHAPTER 22-26 CASE STUDY LECTURE EXAM QUESTIONS WITH CORRECT ANSWERS GRADED A+ 2026

MICROBIOLOGY CHAPTER 22-26
CASE STUDY LECTURE EXAM
QUESTIONS WITH CORRECT
ANSWERS GRADED A+ FOR 2026
ASSURED EXCEL!!
Ab1stbgraderbhasbanbeyebswollenbandbbloodbshot.bThebliningbofbtheblowerblidbisbbrightbred.bTherebisb
abthickbyellowbdischargebinbcornerbofbeye.bWhatbisbthebdiagnosis?b-
bbCORRECTbANSWERSConjunctivitis




WhatbisbthebetiologybforbConjunctivitis?b-bbCORRECTbANSWERSHaemophilusbinfluenzae



Whatbisbthebtreatmentbforbconjunctivitis?bIsbitbcommunicable?b-
bbCORRECTbANSWERSNone,byesbbybdirectbcontactborbfomites.




Swollen,bred,byellowbpus-thickbyellowbdischargeb-
bbCORRECTbANSWERSWhatbsignbleadsbyoubtobbelievebthatbthebinfectionbisbbacteriabinborigin?




tears,blysozyme,bIgAbinbsecretionsb-
bbCORRECTbANSWERSWhatbarebsomebofbthebeye'sbnaturalbdefenses?




Erysipelasb-
bbCORRECTbANSWERSAbwomenbhasbanbextremelybswollenbrightblowerbleg.bItbappearsbshebhasbanbol


dbsurgicalbwoundbinbherbmidbcalf,bwithbroughbscarbtissuebsurroundedbbybpurplishbredbskin.bShebisbin
bablotbofbpain.b3bweeksbagobshebhadbablotbofbmolesbremovedbfrombthebarea.bItbappearedbtobhealbupb


initiallybbutb3bdaysbagobthebincisionbareabstartedblookingbbiggerbratherbthanbsmaller.bShebdidn'tbret
urnbtobthebphysicianbhopingbitbwouldbresolvebit'sbself.bThebpastb3bdaysbthebareabhasbbeginbtobswellb
andbbecomebverybhot.bPatientbsentbtobsurgerybwherebwouldbwasbdebrided.bGramb(+)bcoccibgrowin
gbinbchainsbwerebrecoveredbfrombthebwound.bShebisbtransferredbtobintensivebcarebandbputbonbabhig
hbdosebofbIVbantibioticsbforbthebnextb18bhrs,bbutbbybthebnextbeveningbherblegbisbamputatedbbelowbt

,hebknee.bShebremainedbinbhospitalbforb2monthsbfollowingbsurgerybandbrequiresblongbtermbantibiot
icbandbmult.bskinbgrafts.bonbherbupperbleg.bWhatbdidbthisbpatientbhave?



BecausebClostridiumbisbabrodbshapedbgramb(+)b

andbnotbcoccibshapedb-
bbCORRECTbANSWERSWhatbfeaturesbsuggestbthatbitbisn'tbClostridiumbperfringensbgangrene;binstea


dbofbErysipelas?



Erysipelasb-
bbCORRECTbANSWERSisbanbinfectionbofbthebupperblayersbofbthebskinb(superficial).bThebmostbcommo


nbcausebisbgroupbAbbeta-
hemolyticbstreptococcalbbacteria,bGramb(+)bespeciallybStreptococcusbpyogenes.bErysipelasbresults
binbabfierybredbrashbwithbraisedbedgesbthatbcanbeasilybbebdistinguishedbfrombthebskinbaroundbit.bThe


baffectedbskinbmaybbebwarmbtobthebtouchbit'sbprogressbcanbleadbtobtissuebdestructionbandbsepsisbw


hichbturnbintob(fleshbeatingbbacteriab"NecrotizingbFasciitis")



HowbdoesbthebErysipelasbbacteriumbbegin?b-
bbCORRECTbANSWERSwithbminorbtrauma,bsuchbasbabbruise,bburn,bwound,borbincision.bWhenbthebra


shbappearsbonbthebtrunk,barms,borblegs,bitbisbusuallybatbthebsitebofbabsurgicalbincisionborbabwound.



WhybwasbamputationbthebbestbsolutionbforbthebinfectionbinbthisbcasebofbErysipelas?b-
bbCORRECTbANSWERSBecausebitbhadbprogressedbintob(NecrotizingbFasciitis-


bfleshbeatingbbacteria)bduebtobgroupbAbstreptococcibwhich,bcanbdestroybtissuebasbrapidlybasbabsurge


onbcanbremovebit.



45yrboldbmalebinbgoodbhealth,bwokebwithbpainbinblateralbaspectbofbhisbleftbcalf.bHebthoughtbthebpain
bwasbduebtobanbingrownbhairbandbwentbbackbtobsleep.bNextbmorningbhebexpressedbabsmallbamountb


ofbpusbfrombthebingrownbhairbarea.bOverbnextb8bhrsbthebpatientbdevelopedbanbareabofbcellulitisbonb
theblateralbaspectbofbthebcalfbapprox.b5bbyb10bcm.bAtbthatbtimebsm.bamountbofbpusbwasbexpressedbf
rombthebareabofbthebingrownbhair.bThebnextbmorningbthebareabofbcellulitisbextendedbfrombjustbbelo
wbthebkneebtobjustbabovebthebankle.bVitalbsignsballbwithinbnormalblimits.bPhysicalbexambwasbsignific
antbforbanbareabofbcellulitisbasbdescribedbthatbitbwasbredbandbwarmbtobthebtouchbbutbwithbnobareabo
fbobviousbfluctuance.bNoblymphadenopathybwasbobserved.bCentralbareabofbthebcellulitisbnearbtheb

, areabthatbthebpatientbdescribedbwherebthebingrownbhairbhadbbeen,bwasbpuncturedb3btimesbwithb2
0bguagebneedlebbutbnobpusbdrained.bPatientbreferredbtobsurb-
bbCORRECTbANSWERSStaphylococcusbaureus




Whatbbacteriumbdidbthebinfectedbhairbfolliclebcause?b-
bbCORRECTbANSWERSStaphylococcusbaureus




Whybisbitbnecessarybtobdobanbincisionbandbdrainbthebareabofbcellulitis?b-
bbCORRECTbANSWERSBecausebofbthebextrabfluidbandbinflammationb,bstaphbinfectionbneededbtobbeb


drainedbsobantibioticsbcanbbebmorebeffectivebandbitbalsobgetsbridbofbadditionalbfluidbandbdebris.



Whybwouldbantimicrobialbagentsbalonebnotbbebeffectivebinbtreatmentbofbstaphbinfection?b-
bbCORRECTbANSWERSBecausebitbneedsbtobbebdrainedbsobantibioticsbwillbbebmorebeffectivebbybgetti


ngbridbofbadditionalbfluidbandbdebris



WhatbotherbtypesbofbinfectionsbdobStaphylococcusbaureusbcause?b-
bbCORRECTbANSWERSFolliculitis,bSty,bFuruncle,bCarbundle,bImpetigo




Anbotherwisebhealthyb19-year-
oldbcollegebstudentbwasbadmittedbtobthebemergencybroombwithbabfever,bbadbheadache,bandbabstiffb
neck,bsymptomsbsuggestivebofbmeningitis.bAbspinalbtapbwasbdone.bThebCSFbwasbcloudy,bandbthebce
llbcountbonbthebfluidbwasb500bWBC/ml.bThebdifferentialbWBCbcountbofbthebCSFbshowedbpredomina
ntlybneutrophils.bThebGrambstainbshowedbgram-negativebdiplococci.

Thebmostblikelybetiologicbagentbisb__________.b-bbCORRECTbANSWERSNeisseriabmeningitidis



Ab10-month-
oldbinfantbhasbbecomebconstipatedbandbdemonstratesbmuscularbweaknessbbybherbinabilitybtobsitbu
pborbcrawl.bHerbmusclebtonebisbcontinuingbtobdeteriorate,bandbshebisbbeginningbtobhavebdifficultybh
oldingbherbheadbup.bWhilebquestioningbherbmotherbtobgetbmorebinformation,bthebdoctorbnotedbth
atbthebinfant'sbcerealbhadbbeenbsweetenedbwithbhoneybforbtheblastb10bdays.bWhatbisbablikelybdiagn
osis?b-bbCORRECTbANSWERSInfantbbotulism