NEPHROLOGY肾脏学(pdf36)英文(1)

NEPHROLOGYDr.J.BargmanandDr.M.SchreiberTimothyWelkeandDarrenYuen,chaptereditorsKatherineZukotynski,associateeditorNORMALRENALFUNCTION...............2RenalStructureandFunctionRenalHemodynamicsControlofRenalHemodynamicsTubularReabsorptionandSecretionEndocrineFunctionoftheKidneyMeasurementofRenalFunctionMeasurementofTubularFunctionTheKidneyInPregnancyURINESTUDIES..........................5GeneralUrinalysisMicroscopyCrystalsUrineElectrolytesABNORMALRENALFUNCTION............7ProteinuriaHematuriaELECTROLYTEDISORDERS................9Hyponatremia/HypernatremiaHyponatremiaHypernatremiaHypokalemiaHyperkalemiaACID-BASEDISORDERS...................15RenalContributiontoAcid-BaseBalance1˚MetabolicAcidosis1˚MetabolicAlkalosis1˚RespiratoryAcidosis1˚RespiratoryAlkalosisMixedDisturbancesRENALFAILURE..........................18ACUTERENALFAILURE(ARF).............18TreatmentIndicationsforDialysisinARFPrognosisCHRONICRENALFAILURE(CRF)...........20ClassificationClinicalFeaturesofUremiaComplicationsTreatmentIndicationsforDialysisinCRFDIALYSISANDRENAL.....................21TRANSPLANTATIONDialysisRenalTransplantationMCCQE2002ReviewNotesNephrology–NP1GLOMERULARDISEASE...................22GeneralConsiderationsClassificationofGlomerularDiseaseaccordingtoSyndrome/PresentationClassificationofGlomerularDiseaseaccordingtoEtiologyPrimaryGlomerularDiseaseSecondaryGlomerularDiseaseTUBULOINTERSTITIALNEPHRITIS........27AcuteTubulointerstitialNephritisChronicTubulointerstitialNephritisNSAIDNEPHROPATHY...................28ACUTETUBULARNECROSIS(ATN).........29IschemiaToxinsVASCULARDISEASESOFTHEKIDNEY.....29DIABETESANDTHEKIDNEY..............30HYPERTENSION(HTN)...................31RenovascularHypertensionHypertensionCausedbyRenalParenchymalDiseasePYELONEPHRITIS........................32AcutePyelonephritisChronicPyelonephritisCYSTICDISEASESOFTHEKIDNEY.........33AdultPolycysticKidneyDisease(PCKD)MedullaryCysticDiseaseMedullarySpongeKidneyOTHERSYSTEMICDISEASES..............34ANDTHEKIDNEYHypertensionCausingRenalDiseaseMultipleMyelomaSclerodermaVasculitidesRheumatoidArthritis(RA)CancerInfectionsHIV-AssociatedRenalDiseaseDIURETICS...............................35REFERENCES.............................36NP2–NephrologyMCCQE2002ReviewNotesNORMALRENALFUNCTIONRENALSTRUCTUREANDFUNCTIONNephron❏theindividualrenaltubuleanditsglomerulus❏glomerulus•Bowman’scapsule-blindendoftherenaltubule•glomerularcapillaries-filteringmembranewhichconsistsofA)fenestratedendothelialcellsB)basementmembraneC)podocytesofvisceralepithelialcells•mesangium-consistsofscatteredcellswithcontractileandphagocyticfunctionwhicharecapableoflayingdownbothmatrixandcollagenandofsecretingbiologicallyactivemediators❏proximalconvolutedtubule(PCT)•reabsorbs65%ofglomerularfiltrate,includingglucose,aminoacids,proteins,vitaminsviaactivetransport(waterfollowspassively)•reabsorbs~2/3offilteredNa+mostlyviaelectroneutralNa+–H+exchange•importantsiteofammoniagenesis❏loopofHenle•25%offilteredNa+isabsorbedatthethickascendinglimbmostlyviachannelmediated(Na+-K+-2Cl–)reabsorptionofNa+,K+,andCl–•15%offilteredwaterisremovedinloopofHenle❏distalconvolutedtubule(DCT)•reabsorbs5-10%filteredNa+probablyviadirectlycoupledNaClpathway(withoutK+)•relativelyimpermeabletowater(5%offilteredwaterisremovedinthissegment)•latedistalsegmentisasiteofADHandaldosteroneaction❏juxtaglomerular(J-G)apparatus•adjacenttoglomeruluswhereafferentarterioleenters•consistsof•myoepithelialcells-modifiedgranulatedsmoothmusclecellsinthemediaoftheafferentarteriolethatcontainrenin•maculadensa-specializedregionofthedistaltubulewhichcontrolsreninrelease❏collectingductsystem•finalregulationoffluidandelectrolytebalance•alongwithlatedistalsegment,respondstoADHandaldosteroneRENALHEMODYNAMICS❏RenalBloodFlow(RBF)=20~25%ofcardiacoutput=1200mL/minute❏RenalPlasmaFlow(RPF)=RBFx(1-hematocrit)=600mL/minute❏GlomerularFiltrationRate(GFR)•plasmavolumefilteredacrossglomerulitoBowman’scapsuleperunittime•20%ofRPF=120mL/min•maximalinyoungadulthoodanddecreasesthereafter❏FiltrationFraction(FF)•volumeofplasmafilteredacrossglomeruli,relativetothevolumeofplasmaflowingtothekidneysperunittime•FF=GFR/RPF•asRBFandRPFdecrease,FFmustincreasetopreserveGFR;thisisdonebyAngiotensinII(AII)CONTROLOFRENALHEMODYNAMICS❏goalismaintenanceofGFRinthefaceofvaryingRBF(autoregulation)❏mechanism•decreasedRBF––reninreleasedfromjuxtaglomerularapparatus•reninactivatesangiotensinogen––AngiotensinI•AngiotensinConvertingEnzyme(ACE)activatesAI––AII•AIIconstrictsefferentrenalarterioles,leadingtoanincreaseinfiltrationfraction,maintainingGFRinthefaceofdecreasedRBFFigure1.NephronStructureandFunctionIllustratedbyHeidiMajFigure2.Renin-AngiotensinSystemandtheControlofRenalHemodynamicsIllustratedbyHeidiMajMCCQE2002ReviewNotesNephrology–NP3NORMALRENALFUNCTION...CONT.TUBULARREABSORPTIONANDSECRETION❏theultrafiltratewhichcrossestheglomerularcapillariesintoBowman’sspacestartsitsjourneyalongthetubularsystem❏inthetubule,itisfurthermodifiedbyreabsorption(tubularlumentobloodstream)orsecretion(bloodstreamtotubularlumen)Table1.P