肾功能检验--医药类ppt课件

Laboratory tests of Laboratory tests of renal functionrenal functionLaboratory tests of renal funcAnatomy of KidneyAnatomy of KidneyFunctions of the kidneyFunctions of the kidneyExcretion of Metabolite Waste:urea,uric acid,creatinineUrine Production,regulation of homeostasis,water,acid base balanceEndocrine Function:renin,erythropoietin,1,25-dihydroxycholecalciferolFunctions of the kidneyExcretiRenal function testsRenal function testsDetect renal damageMonitor functional damageDistinguish between impairment and failureRenal function testsDetect renKidney FunctionA plumbers viewKidney FunctionA plumbers viewHow do you know its broken?NO Urine!Clinical symptomsTestsHow do you know its broken?NOWhere can it break?Pre-renalRenalPost-renalWhere can it break?Pre-renalLaboratory tests of renal functionLaboratory tests of renal functionGlomerular Function TestsRenal Tubular Function TestsLaboratory tests of renal funcSection 1 Investigation of Glomerular FunctionRenal Blood Flow:1200-1400ml/minRenal Plasma:600-800ml/min20%of plasma:glomerular filtration GFR:Glomerular Filtrtion Rate Concept Section 1 Investigation of GlRenal CleranceConcept Virtual volume of plasma from which the substance in question has been completely removed during a given time interval.C=UV/P U:urine concentrtion P:plasma con.V:urine flow rateRenal CleranceConceptUsefulness of Renal CleranceFreely filtrated,neither secreted,nor reabsorbed:Inulin:GFR DeterminationFreely Filtrated,small amounts secreted,without reabsorption:Cretinine:GFRFree filtrated,completely reabsorption:Glucose Tubular Maxima Reabsorption RateUsefulness of Renal CleranceFrInulin ClerancePolymer of fructoseMW:5500Free filtration,without secretion and reabsorptionGFRMethod Reference Interval:2.0-2.3ml/minInulin ClerancePolymer of frucEndogenous Creatinine Clearance100g,98%stored in musle,MW:113Cretine phosphate-cretinecretinineFreely filtration,small mounts:secretionExogenous and Endogenous CreatinineGrossly Investigate the GFREndogenous Creatinine ClearancMethod 24h urine collection method modified 4h urine collection method Clerance Correction：Ccr x SBSA/IBSAMethodPlasma ureaPlasma ureaSecreted and reabsorbed by tubules,freely filtratedquick,simple measurementwide reference range 3-8 mmol/Lsensitive but non-specific index of illnessPlasma ureaSecreted and reabs肾功能检验-医药类ppt课件Urea excretionUrea excretionfiltered at glomerulusabout 40%filtered urea is reabsorbed by renal tubules in healthmore urea is reabsorbed if rate of tubular flow is slowtubular flow rate is slow when there is renal hypoperfusionUrea excretionfiltered at glomIncreased plasma ureaIncreased plasma ureaGI bleedtraumarenal hypoperfusiondecreased RBFdecreased ECFVacute renal impairmentchronic renal diseasepost-renal obstructioncalculustumourIncreased plasma ureaGI bleedaUreaUseful test but must be interpreted with great careAlways consider input,output and patients fluid volumeUreaUseful test but must be inPlasma creatininePlasma creatinine50-140 umol/Lincreases in concentration as GFR decreasesanalytical interferences(acetoacetate-DKA)NOT proportional to renal damagePlasma creatinine50-140 umolPlasma CreatinineGFRGFRpCreatpCreat140 mL/min140 mL/min0 mL/min0 mL/minChange within an Change within an individual patient is individual patient is usually more important usually more important than the absolute valuethan the absolute valuePlasma CreatinineGFRpCreat14Plasma creatinine in chronic renal Plasma creatinine in chronic renal disease disease May increase to 1000 umol/LPlot of recipricol of plasma creatinine concentration predicts when intervention is required in end stage renal failureTimeTime1/pCreat1/pCreatPlasma creatinine in chronic rPlasma Uric Acid20%:foods;80%:purine metabolismSmall amounts:conjugated with albuminFree Filtrated,98%-100%:reabsorbedPlasma UA concentration:depend on glomerular filtration and tubular reabsorptionPlasma Uric Acid20%:foods;80%:Progression of chronic renal diseaseProgression of chronic renal diseaseProgression of chronic renal dPlasma Cystatin CCysteine proteinase inhibitorProduced by nucleated cellsMW:13000,free filtration,reabsorbed and metabolized by tubulesPlasma CysC concentrtion:depend on glomerular filtrationPlasma Cystatin CCysteine protCarbamylated hemoglobinUreabloodcyanateHb carbamylatedCarHbARF：no changes(1 weeks)CRF:increaseCarbamylated hemoglobinUreabLaboratory tests of renal functionLaboratory tests of renal functionglomerular filtration rate impracticalcreatinine clearance unreliableplasma creatinine specific but insensitiveplasma urea subject to problemsurine volume often forgotten!Laboratory tests of renal funcSection 2 Investigation of Tubular FunctionDistal nephron Function tests 1.Mosenthal test Concentration dilution test 8 AM:Voiding and Discarded 10,12,14,16,18,20:00 and 8:00 next day:collecting urine samples Determing the urine volume and gravitySection 2 Investigation of Tub2.Urine Osmolarity3.Acute Oliguria Prenal?Renal?2.Urine OsmolarityProximal tubular Function tests 1.Low MW proteins in urine 2.Tubular maximal glucose reabsorption 3.Tubular maximal PAH secretion 4.Amino acide in urine Fanconi SyndromeProximal tubular Function testSection 3 Effective Renal Blood FlowIsotope Method:131I-OIHPAH Clearance:20%:filtrated,80%:secreted by tubulesSection 3 Effective Renal BlooSection 4 Investigation of renal tubular acidosisTubular Acidosis:I,II,III.IVI:distal formII:proximal formSection 4 Investigation of renNH4Cl Loading TestOral administration of NH4ClArtificial Metabolic AcidosisUrine Sample CollectionpH determinationNH4Cl Loading TestOral adminisFraction of HCO3-excretionHCO3-:85-90%:reabsorbed by proximal tubules;10-15%:reabsorbed by distal tubulesOral Administration of NaHCO3Urine CollectionDetermination of PCr,UCr,PHCO3,UHCO3Caculation:FEHCO3=UHCO3.PCr/UCr.PHCO3Fraction of HCO3-excretionHCO