1
Pathophysiology Final Exam u u
Review
Hypopituitarism
Etiologyu ou Congenital,u geneticdisease
o Destructionuofutheuglandu(surgery/uradiation)
o Tumor/umassulesionsuouPituitaryuinfection
o Deficiencyuofuhypothalamicuhormones
Disorders of the posterior pituitary
u u u u
ADH
• ADH:upeptideusynthesizedubyucellsuinutheuhypothalamusu-
>utransportedualonguauneuralupathwayu->ustoreuinupituitary
• NerveuimpulsesucausesustoreduADHutoubeureleaseduintoucirculationubaseduonuserumu
osmolalityu(soubaseduonuwhatuyourubodyuneeds)uouTooumuchuconcentrationu–
uyouuholdupeeutoubalance
▪ Veryusweetujuice,uyouudiluteuituwithuwaterusouyouuholduituinuouTooulittleuc
oncentration-uyouuletuituout
▪ Unsweetenedujuice,uyouupeeuituoututoumakeuitusweet
ExertsueffectsuonutubularucellsuofutheukidneyutoucauseureabsorptionuofuwateruOsmolality
uisuhowuconcentrateduorudilutedutheuserumuis
SensitiveuchangesuinubloodupressureuanducanuleadutoutheureleaseuofuADH
AbnormalusynthesisuofuADHubecauseuofutrauma,ustress,usevereupain,unauseauanducertainu
medications
YouucanucheckuforuosmolalityuonuaubloodutestuUsu
allyu280-310uosm/L
Isotonicu–u300
Lactateuringers,unormalusalineu0.9%u
Hypertonicu–uaboveu300
Hypotonic-ulessuthanu300
Triggeruisuhigherutheuosmolalityutheuhigherutheuconcentration
, 2
SecretesuADHuanduADHuvasoconstrictsuandukeepsufluiduonuboarduCome
sufromuposteriorupituitary
SIADH vs DI
u u
DiabetesuinsipidusuI SIADH
(syndromeuofuinappropriateuADH)
nsipidusu–nouflavor SuperuincreaseduADH
ADHu(regulatesuH2O)uan Deficiency Excessiveusecretion
duvasoconstriction
Serumuosmolality ↑blooduveryuconcentrated ↓blooduveryudiluted
Urineuosmolality ↓ ↑
Urineuoutput Highuurineuoutput Lowuurineuoutput
(diluted)u5-24uLuperuday
Fluiduvolumeustatus Deficit Overload
Sodiumulevel Hypernatremia Hyponatremia
• Diabetesuinsipidusuisuaudisorderuofutheuposteriorulobeuofutheupituitary
• Vasodepressor
• Diabetesuinsipidusuareuunableutouconcentrateutheiruurineuanduexcretesulargeuvolumesuofu
urineuouCNSucomponentutouitubecauseuofusomethinguinutheuADHuex:uheadutrauma,usurg
ery
• Whenukidneysudon’turespondutouADH
• DrugsuthatucauseuDI-uelectrolyteudisorders…
• Weucanuevaluateuantidiureticuhormoneulevelsualonguwithuosmolalityuofutheuurine
• Ifuyouucan’tuexcreteuurineuitustaysuinutheutissueuouPolyuria:ulotsuofuurineuouSodiumuisulowub
ecauseuthereuisuaulotuofufluiduouSyndromeuofuADHuisuauresultuofubrainutumors
• Brainutumorsucanustartusecretinguhormones
ou-surgeryuo
-temperatureuchanges
Disorders of the thyroid
u u u
• ThyroidureleasesuT3uanduT4
, 3
• Bothuareucarriedubyubindinguproteins
• T3ustimulatesumetabolism
• T4uisuinactiveuuntiluconverteduintouT3uinutheutissuesuouNeedsuiodineutouactivate
• Bothuexertunegativeufeedbackuonutheuhypothalamus
• Locateduinutheularynx
• TSHuisuveryuimportantuinuhypouanduhyperthyroidismuanduhowuweumeasureuthyroidu
function
Actions of the thyroid hormone
u u u u
• Mostumajoruorgansuareuaffectedubyualteredulevelsuofuthyroiduhormone
ouMetabolicurate
▪ Glucose,ufat,uanduproteinuusage
▪ Lipidsumobilizedufromuadiposeutissue
▪ Catabolismuofucholesterolubyutheuliver
▪ MuscleuproteinuisubrokenudownuanduuseduasufueluouCardiovascularufunction
▪ Increaseuinuoxygenuconsumption
▪ Increaseuinuvasodilation
▪ Increaseuinuhearturateuanducontractility,uBP
▪ TachycardiauouGIufunction
▪ Absorptionuisuincreased
▪ GIusecretions
▪ Hungry
▪ HyperactiveubowelusoundsuouNeuromuscularueffects
▪ Reactumoreuvigorously
• Hypereflexsive
Clinical manifestations
u
• MetabolicurateuouBasalumetabolicurateucanuincreaseubyu60-
100%uaboveunormaluwithutheulargeuamountsuofuT4uareupresentuouIncreaseuuseuofu
protein,uglucoseuandufat
, 4
lOM oA R u u
cP S D| 4 971 63 1
Muscleuproteinsubrokenudownuanduuseduasufuel
ouChangesuinucholesterol
• CardiovascularufunctionuouWithuincreaseumetabolism=uriseuinuoxygenuc
onsumption,uproductionuofuenduproducts
o Vasodilation
o Increaseublooduvolume,ucardiacuoutput,uHRuanducontractility
• GIuFunction
ouIncreaseuinumotilityuanduproductionuofuGIusecretionsu(diarrhea)uouIncreaseuinua
ppetiteuouWeightuloss
• NeuromuscularueffectsuouChangesuinuskeletalumuscleureaction
▪ Hyperthyroid:ufineumuscleutremor,uextremeunervousness,uanxiety
▪ IncreaseduHR,upalpitations
Diagnostics
• T3
o Lowuinuprimaryuhypothyroidism
• T4
o Measuresuunbounduportionu(producesueffects)uouFreeuT4udecreaseduinuprimaryuh
yperthyroidism
• TSH
ou Differentiatesubetweenuprimaryuandusecondaryuthyroidudisorders
• Radioiodineuuptakeutest
• UltrasounduouCystsuorulesions
• CT/MRI
• NeedleubiopsyuouDoneuwithuguideduultrasound
□uWillutelluifubenignuorumalignant
WeureallyulookuatuTSHuanduisuimportantuinutheunegativeufeedbackuloop
HypothyroidismuisuelevateduTSHubecauseuitukeepsusendingutheusignalutouincreaseuT3uanduT4uW
eumonitorumedicationutherapyuthroughuthis
TSHuincreased,uT3uanduT4udecreased
Hyperthyroidism
• Excessivelyuhighulevelsuofucirculatinguthyroiduhormone
• CommonucausesuouGravesudisease
▪ Enlargeduthyroid
Pathophysiology Final Exam u u
Review
Hypopituitarism
Etiologyu ou Congenital,u geneticdisease
o Destructionuofutheuglandu(surgery/uradiation)
o Tumor/umassulesionsuouPituitaryuinfection
o Deficiencyuofuhypothalamicuhormones
Disorders of the posterior pituitary
u u u u
ADH
• ADH:upeptideusynthesizedubyucellsuinutheuhypothalamusu-
>utransportedualonguauneuralupathwayu->ustoreuinupituitary
• NerveuimpulsesucausesustoreduADHutoubeureleaseduintoucirculationubaseduonuserumu
osmolalityu(soubaseduonuwhatuyourubodyuneeds)uouTooumuchuconcentrationu–
uyouuholdupeeutoubalance
▪ Veryusweetujuice,uyouudiluteuituwithuwaterusouyouuholduituinuouTooulittleuc
oncentration-uyouuletuituout
▪ Unsweetenedujuice,uyouupeeuituoututoumakeuitusweet
ExertsueffectsuonutubularucellsuofutheukidneyutoucauseureabsorptionuofuwateruOsmolality
uisuhowuconcentrateduorudilutedutheuserumuis
SensitiveuchangesuinubloodupressureuanducanuleadutoutheureleaseuofuADH
AbnormalusynthesisuofuADHubecauseuofutrauma,ustress,usevereupain,unauseauanducertainu
medications
YouucanucheckuforuosmolalityuonuaubloodutestuUsu
allyu280-310uosm/L
Isotonicu–u300
Lactateuringers,unormalusalineu0.9%u
Hypertonicu–uaboveu300
Hypotonic-ulessuthanu300
Triggeruisuhigherutheuosmolalityutheuhigherutheuconcentration
, 2
SecretesuADHuanduADHuvasoconstrictsuandukeepsufluiduonuboarduCome
sufromuposteriorupituitary
SIADH vs DI
u u
DiabetesuinsipidusuI SIADH
(syndromeuofuinappropriateuADH)
nsipidusu–nouflavor SuperuincreaseduADH
ADHu(regulatesuH2O)uan Deficiency Excessiveusecretion
duvasoconstriction
Serumuosmolality ↑blooduveryuconcentrated ↓blooduveryudiluted
Urineuosmolality ↓ ↑
Urineuoutput Highuurineuoutput Lowuurineuoutput
(diluted)u5-24uLuperuday
Fluiduvolumeustatus Deficit Overload
Sodiumulevel Hypernatremia Hyponatremia
• Diabetesuinsipidusuisuaudisorderuofutheuposteriorulobeuofutheupituitary
• Vasodepressor
• Diabetesuinsipidusuareuunableutouconcentrateutheiruurineuanduexcretesulargeuvolumesuofu
urineuouCNSucomponentutouitubecauseuofusomethinguinutheuADHuex:uheadutrauma,usurg
ery
• Whenukidneysudon’turespondutouADH
• DrugsuthatucauseuDI-uelectrolyteudisorders…
• Weucanuevaluateuantidiureticuhormoneulevelsualonguwithuosmolalityuofutheuurine
• Ifuyouucan’tuexcreteuurineuitustaysuinutheutissueuouPolyuria:ulotsuofuurineuouSodiumuisulowub
ecauseuthereuisuaulotuofufluiduouSyndromeuofuADHuisuauresultuofubrainutumors
• Brainutumorsucanustartusecretinguhormones
ou-surgeryuo
-temperatureuchanges
Disorders of the thyroid
u u u
• ThyroidureleasesuT3uanduT4
, 3
• Bothuareucarriedubyubindinguproteins
• T3ustimulatesumetabolism
• T4uisuinactiveuuntiluconverteduintouT3uinutheutissuesuouNeedsuiodineutouactivate
• Bothuexertunegativeufeedbackuonutheuhypothalamus
• Locateduinutheularynx
• TSHuisuveryuimportantuinuhypouanduhyperthyroidismuanduhowuweumeasureuthyroidu
function
Actions of the thyroid hormone
u u u u
• Mostumajoruorgansuareuaffectedubyualteredulevelsuofuthyroiduhormone
ouMetabolicurate
▪ Glucose,ufat,uanduproteinuusage
▪ Lipidsumobilizedufromuadiposeutissue
▪ Catabolismuofucholesterolubyutheuliver
▪ MuscleuproteinuisubrokenudownuanduuseduasufueluouCardiovascularufunction
▪ Increaseuinuoxygenuconsumption
▪ Increaseuinuvasodilation
▪ Increaseuinuhearturateuanducontractility,uBP
▪ TachycardiauouGIufunction
▪ Absorptionuisuincreased
▪ GIusecretions
▪ Hungry
▪ HyperactiveubowelusoundsuouNeuromuscularueffects
▪ Reactumoreuvigorously
• Hypereflexsive
Clinical manifestations
u
• MetabolicurateuouBasalumetabolicurateucanuincreaseubyu60-
100%uaboveunormaluwithutheulargeuamountsuofuT4uareupresentuouIncreaseuuseuofu
protein,uglucoseuandufat
, 4
lOM oA R u u
cP S D| 4 971 63 1
Muscleuproteinsubrokenudownuanduuseduasufuel
ouChangesuinucholesterol
• CardiovascularufunctionuouWithuincreaseumetabolism=uriseuinuoxygenuc
onsumption,uproductionuofuenduproducts
o Vasodilation
o Increaseublooduvolume,ucardiacuoutput,uHRuanducontractility
• GIuFunction
ouIncreaseuinumotilityuanduproductionuofuGIusecretionsu(diarrhea)uouIncreaseuinua
ppetiteuouWeightuloss
• NeuromuscularueffectsuouChangesuinuskeletalumuscleureaction
▪ Hyperthyroid:ufineumuscleutremor,uextremeunervousness,uanxiety
▪ IncreaseduHR,upalpitations
Diagnostics
• T3
o Lowuinuprimaryuhypothyroidism
• T4
o Measuresuunbounduportionu(producesueffects)uouFreeuT4udecreaseduinuprimaryuh
yperthyroidism
• TSH
ou Differentiatesubetweenuprimaryuandusecondaryuthyroidudisorders
• Radioiodineuuptakeutest
• UltrasounduouCystsuorulesions
• CT/MRI
• NeedleubiopsyuouDoneuwithuguideduultrasound
□uWillutelluifubenignuorumalignant
WeureallyulookuatuTSHuanduisuimportantuinutheunegativeufeedbackuloop
HypothyroidismuisuelevateduTSHubecauseuitukeepsusendingutheusignalutouincreaseuT3uanduT4uW
eumonitorumedicationutherapyuthroughuthis
TSHuincreased,uT3uanduT4udecreased
Hyperthyroidism
• Excessivelyuhighulevelsuofucirculatinguthyroiduhormone
• CommonucausesuouGravesudisease
▪ Enlargeduthyroid
