多囊性肾脏病变教学课件

CYSTIC

KIDNEYSCYSTICKIDNEYS1Cysticdiseaseofthekidneysinchildhoodisaconfusingandcomplicatedsubject.Alsothecomplexandoftencontradictorynomenclatureusedtodescribecystickidneysisnotanaidtounderstandingthesubject.Thissectionaimstoprovidethesonographerwithasimpleapproachtocystickidneysinchildren.Cysticdiseaseofthekidn2●Multicystickidneyormulticysticdysplastickidney—thisreferstomanycystsinonekidneyoftencontainingsomedysplasticelements.Notallmulticystickidneysaredysplastic.Theconditionisstillconsideredtobenon-hereditary.Ifthemulticystickidneyisunilateral,theotherkidneymaybenormal,hydronephroticordysplastic.Ifbilateral,itisincompatiblewithlife,andinfantsdiesoonafterbirthwithhypoplasticlungsand/orrenalfailure.

Terminology

●Multicystickidneyormultic3●Cysticdysplasia—dysplastickidneyscanbeunilateral

orbilateral,usuallycontaincystsandaredisorganized,

containingectopictissuesuchas

cartilageandmuscle.Theymayfunction.Ultrasonicallytheyusuallyappearsmalland

echogenicwithsmallperipheralcorticalcysts.

Whiledysplastickidneysareoftenhypoplastic,not

allsmallkidneysaredysplastic.Theclinicalfeatures

areveryvariablefromanormalappearing

neonatetoaverydysmorphicinfant.Dysplastic

kidneysareassociatedwithurinarytractobstruction,

andmanysyndromesareassociatedwithcystic

dysplastickidneys.Bilateralrenaldysplasiawill

resultinprogressiverenalfailure.

●Cysticdysplasia—dysplastic4●Polycystickidneydiseasereferstotwo

conditions:

autosomalrecessivepolycystickidneydisease

andautosomaldominantrenaldisease.

●Polycystickidneydiseasere5

—Autosomalrecessivepolycystickidneyswere

previouslyknownasinfantilepolycystic

kidneys.

Confusinglythesekidneysappearhighly

echogeniconultrasound.Thereisgeneralized

dilationofthe

collectingtubules.—Autosomaldominantrenaldiseasewas

previouslyknownasadultpolycystickidney

disease.Cystsdevelopanywherealongthe

nephron.

—Autosomalrecessivepolycyst6Theultimatediagnosisofthecysticrenaldisorderisnotdependentonanyoneimagingmodalityandwilldependonmanyfactors.Sourcesofinformationwhentryingtocometothediagnosisshouldbecollatedfrommanyareas,suchas:Theultimatediagnosisof7●obstetrichistoryofthemother●prenatalhistoryandfetalultrasonography●familyhistoryinformation●clinicalexaminationofthechild●radiologyofpatientandparents●laboratorydata,forexampleDNA●pathologyifabiopsyistakenorfromanyotherfamilymembersthatmayhavehadabiopsyornephrectomyinthepast.●obstetrichistoryofthemot8Ultrasoundisstilltheimagingmodalityofchoiceinchildren,andthefindingsonultrasoundwilldirectfurtherimagingasrequired.Theultrasoundapproachtoanycysticrenaldiseaseinchildrenmustincludeobservationsaboutthefollowing,whichshouldbecarefullystatedintheultrasoundreport.Ultrasoundisstilltheim9●unilateralorbilateralrenalcysts(bilateralinvolvementismorecommoninthegeneticallyinheritedconditions)●sizeofthekidneys—aretheylargeorsmall?●localizationtoonepartofthekidneyordiffuseinvolvementofthewholekidney.Isthereacapsulearoundthecysts?●extrarenalcysts,inparticularintheliverorpancreas●liversizeandhepaticparenchymaappearance●presenceofalargespleenandportalhypertension.●unilateralorbilateralrena10Renalcystsarecommonandmaybehereditary,developmentaloracquired.Theclassificationofcysticrenaldiseasevariesaccordingtotheperspectivefromwhichitiswritten,anddespiteavastamountofliteratureonthesubject,thereisstillnogenerallyacceptedclassificationinexistence.TheearlyPotterclassificationisoflimitedvalueforclinicalpracticebecausenotalltypesrepresentclinicalentities.Renalcystsarecommonand11

Thefollowingclassificationisbynomeansallinclusivebutaimstoemphasizetheimportantclinicalcysticdisorderslikelytobeencounteredbythesonographer.Broadlyspeaking,cysticdiseaseofthekidneyscanbedividedintotwogroupsgeneticdiseaseandnon-geneticdisease:Thefollowingclassificati12●Geneticdisease—autosomalrecessivepolycystickidneydisease(ARPKD)—autosomaldominantpolycystickidneydisease(ADPKD)—juvenilenephronophthisisandmedullarycysticdiseasecomplex—glomerulocystickidneydisease—cystswithmultiplemalformationsyndromes;●Geneticdisease13●Non-geneticdisease—simplecysts—multicysticdysplastickidney—multilocularcysts—acquiredrenalcysticdisease(chronicrenalfailure)—calicealdiverticulum—medullaryspongekidney.●Non-geneticdisease14GeneticdiseaseAutosomalrecessivepolycystickidneydisease(ARPKD)Thisisageneralizedcysticdilationoftherenalcollectingtubulessothatthekidneysarepackedtoagreaterorlesserdegreewithtinylittlecysts(Fig.3.31).Itismuchrarerthantheautosomaldominantformandoccursin1in50000people.Prenataldiagnosiscanbemadebuttherearefalsepositiveandfalsenegativediagnoses.CongenitalhepaticfibrosisisaprerequisiteforthediagnosisofARPKD.GeneticdiseaseAutosomalreces15Figure3.31Autosomalrecessivepolycystickidneydisease(ARPKD).(A)CutsectionofapostmortemspecimeninapatientwithARPKD.Therearemultiplesmallcyststhroughoutthewholeoftherenalsubstance.Itisthesemultiplecystswiththeirposterioracousticenhancementwhichgivethehyperechogenicappearancesonultrasound.(B–D)SonogramsofthekidneyinthreepatientswithARPKDtodemonstratethewidevariationinappearance.Thekidneysarealllarge,overthe95thcentile,andaregloballyhyperechoic.Thevisiblecystsaregenerallysmall,rarelyexceeding2cm.Sometimestheincreaseinechogenicityisprimarilymedullary.ABCDFigure3.31Autosomalrecessiv16

TherearetwotypesofpresentationofARPKD

dependingontheageofthepatientandthedominanceoftherenalorthehepaticdisease.Inthosechildrenwhopresentatbirthorduringtheneonatalperiodtherenaldiseasedominates,whileinthosewhopresentlaterinchildhoodoradolescencetheliverdiseasedominates,withmuchmilderrenalmanifestations.Thehepaticdiseaseinthesechildreniscalledcongenitalhepaticfibrosiswithrenaltubularectasiaandcomestomedicalattentionbecauseofthe

problemsassociatedwithhepaticfibrosis,suchassplenomegaly,portalhypertension,varicesandbleeding.

Therearetwotypesofpre17GrosscysticdilationoftheintrahepaticbiliarytreeisusuallycalledCarolisyndrome.Theoriginaldescriptionwaspurelyofthehepaticdisease,butdilationofthebileductsisseeninearlypresentingARPKDandinthemilderendoftherenalspectrumofrenaltubularectasia.Theriskforasiblingofhavingthisconditionis25%,andtheparents’kidneysshouldbenormal.Grosscysticdilationoft18SonographicAppearances●Thereisawidespectrumofappearancesfrombirthandwithincreasingagethroughoutchildhood.●Thereisbilateralequalinvolvementofthekidneys,andthereniformshapeisusuallymaintained.●Thekidneysmustbebigandaregenerallyoverthe90thcentileforageintheyoung.Withincreasingageandprogressionoftherenaldisease,fibrosismayresultinstabilizationandcomparativedecreaseintherenalsize.SonographicAppearances19●Theinhomogeneousglobalincreaseinechotextureisduetothemyriadofmicrocystspresentingmultipleacousticinterfaces.●Insomeasubcapsularrimofnormalhypoechoiccortexisdiagnostic.●Medullarypyramidsmaybehypoechoicatbirthinsomelessseverelyaffectedbutovertimebecomehyperechoic.Inolderchildrenthecorticomedullarydifferentiationisusuallylost.●Theinhomogeneousglobalinc20●Visiblemacrocystsareuncommonbutcanbeseen,andtheyaregenerallynomorethan1–2cmindiameter.Theybecomemorecommonwithage.●Hepaticfibrosisisalwayspresent.Thehepaticechotexturemaybenormalbut,withincreasingfibrosis,willbecomecoarseandincreasedparticularlyintheperiportalregion.●Visiblemacrocystsareuncom21Figure3.32Dilatedbileductsinautosomalrecessivepolycystickidneydisease(ARPKD).Longitudinalsonogramofthelivershowingthedilatedcysticspaces.Thesearenotcystsbutdilationsofthebileducts.ThelivershouldalwaysbecarefullyexaminedinallchildrensuspectedofhavingARPKD.●Thelivermustbecarefullyexaminedforlesionswhicharecysticdilationsofthebiliarytree.Thehepaticcysticlesionsarenottruecystsbutrather‘out-pouchings’ofthebileducts(Fig.3.32).Figure3.32Dilatedbileducts22●Inolderchildren,becauseofthehepaticfibrosisandliverdisease,portalhypertensionmaybepresent.Evidenceofportalhypertensionwithanenlargedspleenandvaricesmustbesought.●Dopplerexaminationoftheliver,spleenandportalsystemisanessentialpartoftheexaminationinthesechildren.●Inolderchildren,becauseo23FurtherimagingWhenthechildisolderandovertheneonatalperiod,anIVUisperformed.ThiswilldemonstratethestreakyradiatingpatternofcontrastwhichisalmostpathognomonicofARPKD(Fig.3.33).Theimportanceofdoingthisexaminationisthatinshowingthecalicealpatternitwillhelpexcludeothercausesoflargeechogenickidneysintheneonatalperiod,suchasdysplasia.Furtherimaging24ABFigure3.33Intravenousurogram(IVU)inautosomalrecessivepolycystickidneydisease(ARPKD).(A)&(B)TwoexamplesoftheIVUappearancesofARPKD.Theurogramshouldalwaysbeperformedtodemonstratethecalicealpattern.Thiswilldemonstratethetypicalradiatingappearanceofthecontrastasitpassesthroughthecollectingsystemandhelpdifferentiatethedysplastic‘bright’kidneys.ABFigure3.33Intravenousurog25

Ahepaticiminodiaceticacid(HIDA)scanshouldbeperformedatabout1yearofage.IfperformedtooearlytheHIDAscanwillbenormalbut,ifdelayed,theeffectsofthehepaticfibrosiswillhavehadtimetomanifest.Thisinvolvesaradioisotopetracerexcretedinthebileandwilldemonstrateaccumulationandstasisofisotopeinthecysticareasanddelayedclearancefromtheabnormalliver.Alargeleftlobeoflivermayalsobeseen.Ahepaticiminodiaceticac26

CTandMRIarerarelyneededexceptinuncertaincases(Fig.3.34).DMSAscanisnotalwaysperformedbutmayshowfocaldefectsinthekidney.CTandMRIarerarelyneed27Figure3.34MRIexaminationinautosomalrecessivepolycystickidneydisease(ARPKD).ThisinfantwithARPKDhadanMRIbecauseofapnoeicattacks.Theexaminationwasdonetoexcludeapulmonaryarterysling,whichwasnotpresent.Thekidneysarehuge,fillingtheabdomenandcompressingthelungs.Notealsothecysticareasintheliver,whichareareasofbileductdilationasseeninFigure3.32.Figure3.34MRIexaminationin28CYSTIC

KIDNEYSCYSTICKIDNEYS29Cysticdiseaseofthekidneysinchildhoodisaconfusingandcomplicatedsubject.Alsothecomplexandoftencontradictorynomenclatureusedtodescribecystickidneysisnotanaidtounderstandingthesubject.Thissectionaimstoprovidethesonographerwithasimpleapproachtocystickidneysinchildren.Cysticdiseaseofthekidn30●Multicystickidneyormulticysticdysplastickidney—thisreferstomanycystsinonekidneyoftencontainingsomedysplasticelements.Notallmulticystickidneysaredysplastic.Theconditionisstillconsideredtobenon-hereditary.Ifthemulticystickidneyisunilateral,theotherkidneymaybenormal,hydronephroticordysplastic.Ifbilateral,itisincompatiblewithlife,andinfantsdiesoonafterbirthwithhypoplasticlungsand/orrenalfailure.

Terminology

●Multicystickidneyormultic31●Cysticdysplasia—dysplastickidneyscanbeunilateral

orbilateral,usuallycontaincystsandaredisorganized,

containingectopictissuesuchas

cartilageandmuscle.Theymayfunction.Ultrasonicallytheyusuallyappearsmalland

echogenicwithsmallperipheralcorticalcysts.

Whiledysplastickidneysareoftenhypoplastic,not

allsmallkidneysaredysplastic.Theclinicalfeatures

areveryvariablefromanormalappearing

neonatetoaverydysmorphicinfant.Dysplastic

kidneysareassociatedwithurinarytractobstruction,

andmanysyndromesareassociatedwithcystic

dysplastickidneys.Bilateralrenaldysplasiawill

resultinprogressiverenalfailure.

●Cysticdysplasia—dysplastic32●Polycystickidneydiseasereferstotwo

conditions:

autosomalrecessivepolycystickidneydisease

andautosomaldominantrenaldisease.

●Polycystickidneydiseasere33

—Autosomalrecessivepolycystickidneyswere

previouslyknownasinfantilepolycystic

kidneys.

Confusinglythesekidneysappearhighly

echogeniconultrasound.Thereisgeneralized

dilationofthe

collectingtubules.—Autosomaldominantrenaldiseasewas

previouslyknownasadultpolycystickidney

disease.Cystsdevelopanywherealongthe

nephron.

—Autosomalrecessivepolycyst34Theultimatediagnosisofthecysticrenaldisorderisnotdependentonanyoneimagingmodalityandwilldependonmanyfactors.Sourcesofinformationwhentryingtocometothediagnosisshouldbecollatedfrommanyareas,suchas:Theultimatediagnosisof35●obstetrichistoryofthemother●prenatalhistoryandfetalultrasonography●familyhistoryinformation●clinicalexaminationofthechild●radiologyofpatientandparents●laboratorydata,forexampleDNA●pathologyifabiopsyistakenorfromanyotherfamilymembersthatmayhavehadabiopsyornephrectomyinthepast.●obstetrichistoryofthemot36Ultrasoundisstilltheimagingmodalityofchoiceinchildren,andthefindingsonultrasoundwilldirectfurtherimagingasrequired.Theultrasoundapproachtoanycysticrenaldiseaseinchildrenmustincludeobservationsaboutthefollowing,whichshouldbecarefullystatedintheultrasoundreport.Ultrasoundisstilltheim37●unilateralorbilateralrenalcysts(bilateralinvolvementismorecommoninthegeneticallyinheritedconditions)●sizeofthekidneys—aretheylargeorsmall?●localizationtoonepartofthekidneyordiffuseinvolvementofthewholekidney.Isthereacapsulearoundthecysts?●extrarenalcysts,inparticularintheliverorpancreas●liversizeandhepaticparenchymaappearance●presenceofalargespleenandportalhypertension.●unilateralorbilateralrena38Renalcystsarecommonandmaybehereditary,developmentaloracquired.Theclassificationofcysticrenaldiseasevariesaccordingtotheperspectivefromwhichitiswritten,anddespiteavastamountofliteratureonthesubject,thereisstillnogenerallyacceptedclassificationinexistence.TheearlyPotterclassificationisoflimitedvalueforclinicalpracticebecausenotalltypesrepresentclinicalentities.Renalcystsarecommonand39

Thefollowingclassificationisbynomeansallinclusivebutaimstoemphasizetheimportantclinicalcysticdisorderslikelytobeencounteredbythesonographer.Broadlyspeaking,cysticdiseaseofthekidneyscanbedividedintotwogroupsgeneticdiseaseandnon-geneticdisease:Thefollowingclassificati40●Geneticdisease—autosomalrecessivepolycystickidneydisease(ARPKD)—autosomaldominantpolycystickidneydisease(ADPKD)—juvenilenephronophthisisandmedullarycysticdiseasecomplex—glomerulocystickidneydisease—cystswithmultiplemalformationsyndromes;●Geneticdisease41●Non-geneticdisease—simplecysts—multicysticdysplastickidney—multilocularcysts—acquiredrenalcysticdisease(chronicrenalfailure)—calicealdiverticulum—medullaryspongekidney.●Non-geneticdisease42GeneticdiseaseAutosomalrecessivepolycystickidneydisease(ARPKD)Thisisageneralizedcysticdilationoftherenalcollectingtubulessothatthekidneysarepackedtoagreaterorlesserdegreewithtinylittlecysts(Fig.3.31).Itismuchrarerthantheautosomaldominantformandoccursin1in50000people.Prenataldiagnosiscanbemadebuttherearefalsepositiveandfalsenegativediagnoses.CongenitalhepaticfibrosisisaprerequisiteforthediagnosisofARPKD.GeneticdiseaseAutosomalreces43Figure3.31Autosomalrecessivepolycystickidneydisease(ARPKD).(A)CutsectionofapostmortemspecimeninapatientwithARPKD.Therearemultiplesmallcyststhroughoutthewholeoftherenalsubstance.Itisthesemultiplecystswiththeirposterioracousticenhancementwhichgivethehyperechogenicappearancesonultrasound.(B–D)SonogramsofthekidneyinthreepatientswithARPKDtodemonstratethewidevariationinappearance.Thekidneysarealllarge,overthe95thcentile,andaregloballyhyperechoic.Thevisiblecystsaregenerallysmall,rarelyexceeding2cm.Sometimestheincreaseinechogenicityisprimarilymedullary.ABCDFigure3.31Autosomalrecessiv44

TherearetwotypesofpresentationofARPKD

dependingontheageofthepatientandthedominanceoftherenalorthehepaticdisease.Inthosechildrenwhopresentatbirthorduringtheneonatalperiodtherenaldiseasedominates,whileinthosewhopresentlaterinchildhoodoradolescencetheliverdiseasedominates,withmuchmilderrenalmanifestations.Thehepaticdiseaseinthesechildreniscalledcongenitalhepaticfibrosiswithrenaltubularectasiaandcomestomedicalattentionbecauseofthe

problemsassociatedwithhepaticfibrosis,suchassplenomegaly,portalhypertension,varicesandbleeding.

Therearetwotypesofpre45GrosscysticdilationoftheintrahepaticbiliarytreeisusuallycalledCarolisyndrome.Theoriginaldescriptionwaspurelyofthehepaticdisease,butdilationofthebileductsisseeninearlypresentingARPKDandinthemilderendoftherenalspectrumofrenaltubularectasia.Theriskforasiblingofhavingthisconditionis25%,andtheparents’kidneysshouldbenormal.Grosscysticdilationoft46SonographicAppearances●Thereisawidespectrumofappearancesfrombirthandwithincreasingagethroughoutchildhood.●Thereisbilateralequalinvolvementofthekidneys,andthereniformshapeisusuallymaintained.●Thekidneysmustbebigandaregenerallyoverthe90thcentileforageintheyoung.Withincreasingageandprogressionoftherenaldisease,fibrosismayresultinstabilizationandcomparativedecreaseintherenalsize.SonographicAppearances47●Theinhomogeneousglobalincreaseinechotextureisduetothemyriadofmicrocystspresentingmultipleacousticinterfaces.●Insomeasubcapsularrimofnormalhypoechoiccortexisdiagnostic.●Medullarypyramidsmaybehypoechoicatbirthinsomelessseverelyaffectedbutovertimebecomehyperechoic.Inolderchildrenthecorticomedullarydifferentiationisusuallylost.●Theinhomogeneousglobalinc48●Visiblemacrocystsareuncommonbutcanbeseen,andtheyaregenerallynomorethan1–2cmindiameter.Theybecomemorecommonwithage.●Hepaticfibrosisisalwayspresent.Thehepaticechotexturemaybenormalbut,withincreasingfibrosis,willbecomecoarseandincreasedparticularlyintheperiportalregion.●Visiblemacrocystsareuncom49Figure3.32Dilatedbileductsinautosomalrecessivepolycystickidneydisease(ARPKD).Longitudinalsonogramofthelivershowingthedilatedcysticspaces.Thesearenotcystsbutdilationsofthebileducts.ThelivershouldalwaysbecarefullyexaminedinallchildrensuspectedofhavingARPKD.●Thelivermustbecarefullyexaminedforlesionswhicharecysticdilationsofthebiliarytree.Thehepaticcysticlesionsarenottruecystsbutrather‘out-pouchings’ofthebileducts(Fig.3.32).Figure3.32Dilatedbileducts50●Inolderchildren,becauseoft