HARRISON BASED QUESTIONS ( JULY 2024 ).pdf

This document contains 35 questions based on Harrison's Principles of Internal Medicine.

This was prepared for internal medicine post graduates as a part of the Harrison reading program.

The reference page number in the book is also cited here.

1. HARRISONBASEDQUESTIONS
1._________isthemajorcauseofrapidlydevelopingbilateralblindnessinpatients>60years.
Theischemicopticneuropathyinduced
bygiantcellarteritis
(Page113)
2.Lemierre’ssyndromeismostcommonlycausedby_________.
Fusobacteriumnecrophorum
(Pageno.254)
Lemierresyndrome(LS)isararecomplicationofbacterialpharyngitis/tonsillitisandinvolvesan
extensionoftheinfectionintothelateralpharyngealspacesoftheneckwithsubsequentseptic
thrombophlebitisoftheinternaljugularvein(s).Itisaccompaniedbymetastaticinfections,most
commonlyofthelungbutwithpossibleinvolvementofthejoints,bones,liver,meninges,andbrain.
FusobacteriumnecrophorumisaGramnegativeanaerobicbacillus.
3.Whichofthefollowingisanincorrectstatementregardingtigecycline?
A.AvailableonlyinIVformulation.
B.TigecyclinehasactivityagainstMRSA,vancomycin-sensitiveenterococci,Enterobacterales,and
Bacteroidesspecies;
C.IthasgoodactivityagainstP.aeruginosa.
D.Thereisanincreasedriskofdeathamongpatientsgiventigecyclinealone
Cisincorrect.TigecyclinehasnoactivityagainstPseudomonasaeruginosa.
(Pageno.1159)
Tigecyclineisaglycylcyclinederivedfromminocycline.Itisindicatedinthetreatmentofcomplicated
skinandsofttissueinfections,complicatedintraabdominalinfections,andcommunity-acquiredbacterial
pneumoniainadults.
Thisdrughasbeenusedincombinationwithcolistinforthetreatmentofseriousinfectionswith
multidrug-resistantgramnegativeorganisms.Apooledanalysisof13clinicaltrialsfoundanincreased
riskofdeathandtreatmentfailureamongpatientsgiventigecyclinealone;asaresult,theFDAmandated
ablackboxwarning.

2. 4.Agatstonscoreisrelatedto______.
A.Intracranialatherosclerosis
B.Calcificationinthecoronaryarteries
C.Urolithiasis
D.Deepvenousthrombosis
B.Calcificationinthecoronaryarteries
(Pageno.1836)
Agatstonscoreisasemi-automatedtooltocalculateascorebasedontheextentofcoronaryartery
calcificationdetectedbyanunenhancedlow-doseCTscan,whichisroutinelyperformedinpatients
undergoingcardiacCT.
5.Inheartfailure,afewhormonesareupregulatedandexertbeneficialeffectsontheheart,
kidneyandvasculature.Namethem.
●Natriureticpeptides(atrialnatriureticpeptide[ANP]andB-typenatriureticpeptide[BNP])

3. ●Prostaglandins(prostaglandinE1
[PGE1]andprostacyclin[PGI2])
●Bradykinin
●Adrenomedullin
●Nitricoxide
(Page1934)
6.Theelevatedlevelof_______instoolisconsideredadiagnostictestinproteinlosingenteropathy.
Alpha1antitrypsin
(Pageno.2466)
Protein-losingenteropathyreferstoalargegroupofGIandnon-GIdisorderscharacterizedby
hypoproteinemiaandedemaintheabsence
ofliverdiseasewithreducedproteinsynthesis,orkidneydiseasewithproteinuria.Thesediseasesare
characterizedbyexcessproteinlossin
theGItract.
7.ThemostefficaciousmethodstomonitortreatmentandresolutionofvitaminDdeficiencyare
serumandurinarycalciummeasurements.InpatientswhoarevitaminDrepleteandaretaking
adequatecalciumsupplementation,the24-hurinarycalciumexcretionshouldbeintherangeof
______/24h.
100–250mg
(Pageno.3169)
Lowerlevelssuggestproblemswithadherence
tothetreatmentregimenorwithabsorptionofcalciumorvitaminDsupplements.Levels>250mg/24h
predisposetonephrolithiasis
andshouldleadtoareductioninvitamindosageand/orcalciumsupplementation.
***********************************
8.________isthemostcommonsymptominmyeloma.
Bonepain
(Pageno.869)
Bonepainisthemostcommonsymptominmyeloma,affectingnearly70%ofpatients.Persistent
localizedpainusuallysignifiesa

4. pathologicfracture.Thebonelesionsofmyelomaarecausedbytheproliferationoftumorcells,activation
ofosteoclaststhatdestroybone,
andsuppressionofosteoblaststhatformnewbone.Theincreasedosteoclastactivityismediatedby
osteoclastactivatingfactors(OAFs)
producedbythemyelomacells(mediatedbyseveralcytokines,includingIL-1,lymphotoxin,vascular
endothelialgrowthfactor[VEGF],
receptoractivatorofnuclearfactor-κB[RANK]ligand,macrophageinhibitoryfactor[MIP]-1α,and
tumornecrosisfactor[TNF]).The
bonelesionsarelyticinnatureandarerarelyassociatedwithosteoblasticnewboneformationdueto
theirsuppressionbydickhoff-1(DKK-1)producedbymyelomacells.Therefore,radioisotopicbone
scanningislessusefulindiagnosisthanisplainradiography.
Thebonylysisresultsinsubstantialmobilizationofcalciumfrombone,andseriousacuteandchronic
complicationsofhypercalcemia
maydominatetheclinicalpicture.Localizedbonelesionsmaycausethecollapseofvertebrae,leadingto
spinalcordcompression
9.ThecausativeagentandtheantibioticofchoiceinPontiacfever?
Legionella.Noantibioticsarerequired.
(Pageno.1253)
Pontiacfeverisdescribedasaninfluenza-likeillnesswhoseprimarysymptomsarefever,headache,
myalgias,chills,vertigo,nausea,vomiting,anddiarrhea.ComparedwithLegionellapneumonia,Pontiac
feverisamilder,self-limitedillnessthatisdefinedbytheabsenceofpneumonia.Althoughstudies
haveshownthatPontiacfeverisassociatedwithexposuretohighercountsofcolony-formingunitsin
watersources,theroleofthepathogeninthediseaseisnotclear.Symptomsusuallydevelop24–48h
afterexposureandcanlastfor2–5days.SincemanyotherillnessesresemblePontiacfever,thediagnosis
usuallyreliesontherecognitionoftypicalclinicalfeaturesduringanoutbreaksituation;therefore,cases
arelikelytobemissedevenwhenpatientspresentforhealthcare.Studiesdocumentingspecific
LegionellaspeciesasthecauseofPontiacfeverclustersfindthatmostareduetoL.pneumophila
exposure;however,non-pneumophilaspeciessuch
asL.anisahavealsobeenassociatedwiththispresentation.
10.ThemechanismofactionofRanolazineis
Inhibitionofthelateinwardsodiumcurrent(INa).
(Pageno.2042)
Ranolazine,apiperazinederivative,maybeusefulforpatientswithchronicanginadespitestandard
medicaltherapy.Itsantianginalactionisbelievedtooccurviainhibitionofthelateinwardsodium
current(INa).ThebenefitsofINa

5. inhibitionincludelimitationoftheNaoverloadofischemicmyocytesandpreventionofCa2+overload
viatheNa+–Ca2+exchanger.
Adoseof500–1000mgorallytwicedailyisusuallywelltolerated.Ranolazineiscontraindicatedin
patientswithhepaticimpairment.
11.Youareplanningtoliberateapatientfromamechanicalventilator.Mentiontheextubation
readinesscriteria.
(Pageno.2234)
12.__________________wasapprovedbytheU.S.FoodandDrugAdministrationandwaswidely
usedinthetreatmentofsepsis.Alarge,randomized,double-blind,placebo-controlled,multicenter
trialof____inseveresepsis(thePROWESStrial)wasreportedin2001;thedatasuggestedan
absoluteriskreductionofupto6%among____-treatedpatientswithseveresepsis.However,
subsequentphase3trialsfailedtoconfirmthiseffect,andthedrugwaswithdrawnfromthe
market.Itisnolongerrecommendedinthecareofsepsisorsepticshock.
RecombinantactivatedproteinC(aPC)
(Page2249)
13.Howdoeshypomagnesemiacausehypocalcemia?
HypocalcemiaassociatedwithhypomagnesemiaisduetobothdeficientPTHreleaseandimpaired
responsivenesstothehormone.Patientswithhypocalcemiasecondarytohypomagnesemiahavelow

6. levelsofcirculatingPTH,indicativeofdiminishedhormonereleasedespiteamaximumphysiologic
stimulusbyhypocalcemia.
(Page3186)
14.ThemostcommonformofsyndromicHeritableThoracicAorticAneurysmDiseaseis
_____,causedbymutationsinthegenefor______.
Marfan'ssyndrome:fibrillin-1(FBN1)
(Page3229)
***************************************
15.
a.Whatisallodynia?
b.Whatishyperalgesia?
Allodynia:Painduetoastimuluswhichdoesnotnormallyprovokepain.
Hyperalgesia:Increasedpainintensityinresponsetothesamenoxiousstimulus;e.g.,pinprickcauses
severepain
(Pageno.91)
16.Mentionafewcausesofanuria.
●Completebilateralurinarytractobstruction;
●Avascularcatastrophe(dissectionorarterialocclusion);
●Renalveinthrombosis;
●Acutecastnephropathyinmyeloma;
●Renalcorticalnecrosis;

7. ●Severeacutetubularnecrosis;
●CombinedtherapywithNSAIDs,ACEinhibitors,and/orARBs;and
●Hypovolemic,cardiogenic,orsepticshock
(Pageno.336)
17.Whataretheeffectsofmetabolicacidosisontherespiratorysystem,CVS&CNS?
Metabolicacidosishasprofoundeffectsontherespiratory,cardiac,andnervoussystems.
#ThefallinbloodpHisaccompaniedbyacharacteristicincreaseinventilation,especiallythetidal
volume(Kussmaulrespiration).
#Intrinsiccardiaccontractilitymaybedepressed,butinotropicfunctioncanbenormalbecauseof
catecholaminerelease.Bothperipheralarterialvasodilationandcentralvenoconstrictionmay
bepresent;thedecreaseincentralandpulmonaryvascularcompliancepredisposestopulmonaryedema
withevenminimalvolumeoverload.
#CNSfunctionisdepressed,withheadache,lethargy,stupor,and,insomecases,evencoma.Glucose
intolerancemayalsooccur.
(Pageno.361)
18.WhatisFaget'ssign?
Relativebradycardiainassociationwithfever(Temperature-pulsedissociation).
ItwasoriginallydescribedbyJean-CharlesFagetinpatientswithyellowfever(1859)
(Pageno.943)
Liebermeisterrule:Definingtherelationshipbetweenpulsefrequencyandbodytemperatureinfever.In
fever,whenthebodytemperatureincreasesbyonedegreecentigrade,thepulsefrequencyincreasesby
eightbeatsperminute.
19._________isthemostcommonmanifestationcausedbyC.difficile.
Diarrhoea
(Pageno1068)

8. 20.Mentionafewmedicationscausingweightgain.
#Medicationsfordiabetes(insulin,sulfonylureas,thiazolidinediones),
#Steroidhormones,
#Antipsychoticagents(clozapine,olanzapine,risperidone),
#Moodstabilizers(lithium),
#Antidepressants(tricyclics,monoamineoxidaseinhibitors,paroxetine,mirtazapine),and
#Antiepilepticdrugs
(valproate,gabapentin,carbamazepine).
Othermedications,suchasnonsteroidalanti-inflammatorydrugsandcalciumchannelblockers,may
causeperipheraledemabutdonotincreasebodyfat.
(Page3087)
21.________IgGantibodiesarefoundin>90%ofpatientswithMillerFisherSyndrome.
Anti-GQ1b
(Pageno.3502)
TheclassictriadinMillerFischersyndromeisataxia,areflexia,andophthalmoparesis.
*************************************

9. 22.WhatisSAAG?Mentionany5causesoflowSAAGascites
SAAG:SerumAscitesAlbuminGradient
TheSAAGiscalculatedbysubtractingtheasciticalbuminconcentrationfromtheserumalbuminlevel.
ASAAG<1.1g/dL(lowSAAG)indicatesthattheascitesisnotrelatedtoportalhypertension.
CausesofLowSAAGascites:
-Tuberculousperitonitis
-Peritonealcarcinomatosis
-Pancreaticascites
-Nephroticsyndrome
-Biliaryleak
(Page323)
TheSAAGisusefulfordistinguishingascitescausedbyportalhypertensionfromnonportalhypertensive
ascites.
TheSAAGreflectsthepressurewithinthehepaticsinusoidsandcorrelateswiththehepaticvenous
pressuregradient.
ASAAG≥1.1g/dLreflectsthepresenceofportalhypertensionandindicatesthattheascitesisdueto
increasedpressureinthehepaticsinusoids.AccordingtoStarling’slaw,ahighSAAGreflectstheoncotic
pressurethatcounterbalancestheportalpressure.Possiblecausesincludecirrhosis,cardiacascites,
hepaticveinthrombosis(Budd-Chiarisyndrome),sinusoidalobstructionsyndrome(veno-occlusive
disease),ormassivelivermetastases.
Forhigh-SAAG(≥1.1)ascites,theasciticproteinlevelcanprovidefurthercluestotheetiology.An
asciticproteinlevelof≥2.5g/dLindicatesthatthehepaticsinusoidsarenormalandareallowingpassage
ofproteinintotheascites,asoccursincardiacascites,earlyBudd-Chiarisyndrome,orsinusoidal
obstructionsyndrome.Anasciticproteinlevel<2.5g/dLindicatesthatthehepaticsinusoidshavebeen
damagedandscarredandnolongerallowpassageofprotein,asoccurswithcirrhosis,lateBudd-Chiari
syndrome,ormassivelivermetastases.
Pro-brain-typenatriureticpeptide(BNP)isanatriuretichormonereleasedbytheheartasaresultof
increasedvolumeandventricularwallstretch.HighlevelsofBNPinserumoccurinheartfailureandmay
beusefulinidentifyingheartfailureasthecauseofhigh-SAAGascites.
23.Aserumferritinlevelof<______isdiagnosticofabsentironstoresinthebody.

10. 15mcg/L
(Page750)
Freeironistoxictocells,andthebodyhasestablishedanelaboratesetofprotectivemechanismstobind
ironinvarious
tissuecompartments.Withincells,ironisstoredcomplexedtoproteinasferritinorhemosiderin.
Apoferritinbindstofreeferrousironandstoresitintheferricstate.Asferritinaccumulateswithincellsof
thereticuloendothelial(RE)system,proteinaggregatesareformedashemosiderin.Ironinferritinor
hemosiderincanbeextractedforreleasebytheREcells,althoughhemosiderinislessreadilyavailable.
Understeady-stateconditions,theserumferritinlevelcorrelateswithtotalbodyironstores;thus,the
serumferritinlevelisthemostconvenientlaboratorytesttoestimateironstores.Thenormalvaluefor
ferritinvariesaccordingtotheageandgenderoftheindividual.Adultmaleshaveserumferritin
valuesaveraging100μg/L,whileadultfemaleshavelevelsaveraging30μg/L.Asironstoresare
depleted,theserumferritinfallsto<15μg/L.Suchlevelsarediagnosticofabsentbodyironstores.
24.WhatisthedoseofrivaroxabanadministeredtoapatientwithDVT?Howshouldrivaroxaban
betakeninrelationtofood?
Rivaroxabanisstartedatadoseof15mgtwicedailyfor21daysandisthenreducedto20mgoncedaily
thereafter.
ForsecondaryVTEprevention,thedoseofrivaroxabancanbeloweredto10mgoncedaily.
Atdosesof15or20mgoncedaily,rivaroxabanmustbeadministeredwithfoodtoenhanceabsorption.
(Page936)
25.Nameanytwointestinalroundworms&twotissueroundworms.
Intestinalroundworms-Ascarislumbricoides,Enterobiusvermicularis
Tissueroundworms-Wuchereriabancrofti,Onchocercusvolvulus
(Page1697)
Themajorintestinalroundwormsare
#Ascarislumbricoides
#Necatoramericans

11. #Ancylostomaduodenale
#Trichuristrichiura
#Enterobiusvermicularis
#Strongyloidesstercoralis
Takentogether,infectionscausedbyintestinalroundwormsarethemostcommoninfectionsintheworld.
Theseinfectionsaremostcommoninresource-poordevelopingcountries,especiallywherepeople
defecateoutsideand/orhumanfecesisusedasfertilizer(“nightsoil”).Infectionistransmittedeitherby
ingestionofova(A.lumbricoides,T.trichiura,andE.vermicularis)orbyactivepenetrationoftheskinby
larvae(hookwormsandS.stercoralis)
Themajordiseasescausedbytissueroundwormsare
#filariasis
#angiostrongyliasis
#gnathostomiasis
#trichinellosis
Fourfilarialspeciescausethreedistinctdiseases:lymphaticfilariasis(WuchereriabancroftiandBrugia
malayi),riverblindness(Onchocercusvolvulus),andloiasis(Loaloa,theAfricaneyeworm).Humans,
themajorreservoir,acquiretheseinfectionsfrombitesofinfectedarthropods.Thelarvaedevelopinto
adults,whichremainstaticintissue:thelymphaticsforlymphaticfilariasisandsubcutaneoustissueforO.
volvulusandL.loa.Afteradultsmate,next-stagelarvaeareproduced,andtheirmigrationcauses
additionaldamage.
Trichinellaspiralislarvaepenetratetheintestineandmigratewidely,withapreferenceforskeletaltissue;
thereleaseofeosinophilsandIgEcausesmusclesorenessandmaycausepalpebralswellingandother
manifestationsofgeneralizedallergicreactions.
Gnathostomaspinigerumlarvaepenetratetheintestineandmigrate,showingapreferencefortheskin,
eyes,andmeninges.Mechanicaldamagefromthemigrationandinflammationproducedbytheresultant
immunereactioncancauseboil-likelesionsontheskin,painfuleyedamage,andeosinophilicmeningitis.
Angiostrongyluscantonensisisthemostcommonparasiticcauseofeosinophilicmeningitis.Ingested
larvaepenetratetheintestineandmigratetothebrainandmeninges,wheretheyquicklydieandattract
massivenumbersofeosinophils.Althoughcomplicationscanoccur,mostindividualsrecover
spontaneously.
AlthougheosinophilicmeningitiscausedbyG.spinigerumislesscommonthanthatcausedbyA.
cantonensis,itisoftenmoresevereandcanresultinparalysisorbrainhemorrhage.

12. Guineaworminfection(dracunculiasis,causedbyDracunculusmedinensis)hasbeenalmosteradicated.
26.Themurmuroftricuspidvalveregurgitationgetslouderwithdeepinspiration.Thissignis
called______.
Carvallo'ssign
(Page1992)
27.Whicharetheorganismsresponsibleforstruvitestones?
Urease-producingbacteriasuchasProteusmirabilis,Klebsiellapneumoniae,orProvidencia
species.
(Pageno.2373)
Alsoknownasinfectionstonesortriplephosphatestones.
UreaseproducedbythesebacteriahydrolyzesureaandmayelevatetheurinepHtoasupraphysiologic
level(>8.0).Struvitestonesmaygrowquicklyandfilltherenalpelvis(staghorncalculi).
Struvitestonesrequirecompleteremovalbyaurologist.Newstoneformationcanbeavoidedbythe
preventionofUTIs.

13. 28.Whatarethevariousmanifestationsoftheconditioncausedbyreducedactivityoftheenzyme
cystathionineβ-synthase?
Lensdislocation,thromboticvasculardisease,intellectualdisability,osteoporosis
(Pageno.3271)
Reducedactivityofcystathionineβ-synthaseresultsinclassichomocystinuria.Itisthemostcommon
formofhomocystinuria.
Cystathionineβ-synthaseisapyridoxalphosphate–dependentenzyme.Itcondenseshomocysteinewith
serinetoformcystathionine.
Mostpatientspresentbetween3and5yearsofagewithdislocatedopticlensesandintellectualdisability
(inabouthalfofcases).Somepatientsdevelopamarfanoidhabitusandradiologicevidenceof
osteoporosis.
Life-threateningvascularcomplications(affectingcoronary,renal,andcerebralarteries)canoccur
duringthefirstdecadeoflifeandarethemajorcauseofmorbidityandmortality.
Classichomocystinuriacanbediagnosedwithanalysisofplasmaaminoacids,showingelevated
methionineandpresenceoffreehomocysteine.
Totalplasmahomocysteineisalsoextremelyelevated(usually>100μM).Elevated
levelsofmethioninecanbealsodetectedbyneonatalscreening,butmildervariantscanbemissedbythis
approach.
Treatmentconsistsofaspecialdietrestrictedinproteinandmethionine.Inapproximatelyhalfofpatients,
oralpyridoxine(25–500mg/d)producesafallinplasmamethionineandhomocysteineconcentrationin
bodyfluids.FolateandvitaminB12deficiencyshouldbepreventedbyadequatesupplementation.
Betaineisalsoeffectiveinreducinghomocysteinelevelsbyfavoringitsremethylationtomethionine.
***********************************************
29.WhatisIOU?
IUOisdefinedasthepresenceofelevatedinflammatoryparameters(CRPorESR)onmultipleoccasions
foraperiodofatleast
3weeksinanimmunocompetentpatientwithnormalbodytemperature,forwhichafinalexplanationis
lackingdespitehistory-taking,
physicalexamination,andtheobligatorytests.
(Page145)

14. Theobligatoryteststobedoneare
CBC,ESR,CRP,Electrolytes,Creatinine,Liverfunctiontests(Totalbilirubin,Directbilirubin,
SGOT,SGPT,ALP,Totalprotein,Albumin),Proteinelectrophoresis,Creatinephosphokinase,
Ferritin,Antinuclearantibodies,Rheumatoidfactor,URE,Bloodculture(n=3),Urineculture,CXR
,USGabdomen,TSTorIGRA
30.Manualpressuretotheskinofpatientswithcertainskindiseasesmayelicittheseparationofthe
epidermis,whichiscalled_______sign.
Nikolsky'ssign
(Page400)
Seenin
●Pemphigus
●Toxicepidermalnecrolysis,
●Stevens-Johnsonsyndrome
31.Heavymenstrualbleedingisdefinedquantitativelyasalossof>____mLofbloodpercycle,
basedonthequantityofbloodloss
requiredtoproduceiron-deficiencyanemia.Heavymenstrualbleedingisasubjectivesymptom.
Whatarethepredictorsofheavymenstrualbleeding?
80
Acomplaintofheavymensesissubjectiveandhasapoorcorrelationwithexcessive
bloodloss.Predictorsofheavymenstrualbleedinginclude
#bleedingresultinginiron-deficiencyanemiaoraneedforbloodtransfusion,
#passageofclots>1inchindiameter,and
#changingapadortamponmorethanhourly.
(Pageno.453)
32.InapatientwithAF,howisadequateratecontroldefined?
Adequateratecontrolisdefinedasarestingheartrateof<80beats/minthatincreasesto<100
beats/minwithlightexertion,suchaswalking.
Ifitisdifficulttoslowtheventricularrateto

15. thatdegree,allowingarestingrateofupto110beats/minisacceptableprovideditdoesnotcause
symptomsandventricularfunctionisnormal.
(Pageno.1905)
33.HALTPKD,TAMPO,ALADIN,DIPAK
Thesetrialsarerelatedtowhichcondition?
Autosomaldominantpolycystickidneydisease(ADPKD)
(Pageno.2353)
HALTPKD:BloodpressureinearlyADPKD
TAMPO:TolvaptaninpatientswithADPKD
ALADIN:EffectoflongactingsomatostatinanalogueonkidneyandcystgrowthinADPKD
DIPAK:EffectoflanreotideonkidneyfunctioninpatientswithADPKD
34.Mentionafewcausesofrecurrentacutepancreatitis.
Thetwomostcommonetiologicfactorsarealcoholandcholelithiasis.
(Pageno.2658)
Approximately25%ofpatientswhohavehadanattackofacutepancreatitishavearecurrence.
Inpatientswithrecurrentpancreatitis
withoutanobviouscause,thedifferentialdiagnosisshouldencompassoccultbiliarytractdisease,
includingmicrolithiasis,hypertriglyceridemia,pancreaticcancer,andhereditarypancreatitis.Other

16. diseasesofthebiliarytreeandpancreaticductsthatcancauseacutepancreatitisincludecholedochocele;
ampullarytumors;pancreasdivisum;andpancreaticductstones,stricture,andtumor.Approximately
2–4%ofpatientswithpancreaticcancerpresentwithacutepancreatitis.
35.ApatientwithshortstaturewasfoundtohaveLaronsyndrome.Howisthegrowthhormone
levelandIGF-1levelinapatientwithLaronsyndrome?
ThebasalGHiselevatedbutIGF-1islow.
(Pageno.2899)
Laronsyndromeischaracterizedbyclinicalfeaturesofgrowthhormone(GH)deficiencyandbiochemical
findingssuggestiveofGHresistance.Itisafullypenetrantautosomalrecessivediseaseseenmore
commonlyinconsanguineousfamilies.GHresistanceoccursduetodefectsintheGHreceptororpost
receptorpathways.LaronsyndromeisunresponsivetoexogenousGHtherapy.ExogenousIGF-1
administrationisthetreatmentofchoice.