basic pathophysiology.pdf

Urine reducing substances

1. Chapter 1
Introduction of Pathophysiology
Dr. Liu Rui([email protected])
Department of Physiology and Pathophysiology
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2. 1. Nature and Aims of Pathophysiology
Basicmedicine―→Clinicalmedicine―→Practice
―→Qualifieddoctor
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Pathophysiologyisoneofbasicmedical
sciences,whichfocusonsickordisordered
life.

3. Basicmedicalcourses
normalbody disorderedbody
structurefunction structurefunction
metabolism metabolism
Anatomy Pathoanatomy
BiologyPhysiology Pathophysiology
HistologyBiochemistry
about drugs----Pharmacology
Clinicalmedicalcourses
Internalmedicine,Surgery,Pediatrics,etal.
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4. Pathophysiologyisthestudyoftheunderlying
mechanismsbywhichdiseasesoccurand
develop,andthestudyofthechangesby
diseaseswithinthebody.Itprovidesa
theoreticalbasisfortheprevention,diagnosis
andtreatment.
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5. Structure
Intact body
Function Metabolism
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6. Alterations
in structure
Disease
Alterations
in function
Alterations in
metabolism
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7. Pathophysiologyemphasizes the
developmental process of diseases.
Disruption of the body’s homeostasis;
Alterationsin function, metabolism
Mechanismsinvolved.
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8. 2. Content of pathophysiology
Systemic and organic pathophysiology
Fundamental pathological process
General concept of disease
Pathophysiology in diseases
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9. ExperimentalstudyReproducediseasemodelin
animals,isolatedorgansandcells,andobserveor
performsomething.
ClinicalstudyObservedirectlythepatient’ssymptom,
laboratorytesting,therulesofevolution;studythe
treatmentandprognosis.
EpidemiologicalstudyStudythecauseorconditional
factors,riskfactors,rulesofdevelopmentofsome
infectivediseases
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3. Research Methods for Pathophysiology

10. Summary
1.Pathophysiologyisoneofbasicmedicalscienceswhich
studytherulesoforiginandevolutionofdiseasesand
theunderlyingmechanisms---“thephysiologyof
disease”.
2.Pathophysiologyfocusesonthealterationsinfunction
andmetabolismofthebodyandthemechanisms
underlyingthedevelopmentofdiseases.
3.Pathophysiologyplaysanimportantroleinbridge
linkingbasicmedicalsciencestoclinicalmedicine.
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11. PathophysiologyPhysiology
Different targets
Normal bodySick body
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12. PathophysiologyPathoanatomy
Different Points
Function
Metabolism
Mechanism
Structure
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13. Pathophysiology
Bridge course
Basicmedicine Clinical medicine
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14. Chapter 2
General Concepts of Diseases
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15. 1. Basic Concepts
1-1Health
Nodiseasesorinfirmity.
Astateofcompletewell-beingofallaspects:physical,
mental,social.
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1-2Disease
Diseaseisanabnormallifeprocesscausedbycertain
pathogenicfactors,deviationfromthenormalstatus
includingstructure,functionormetabolism.

16. Diseaseisadisorderedstateofthebodydueto
pathogenicagents-hostinteractions.
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Homeostasis:theprocessthattheinternal
environmentofanorganismtendstoremain
balancedandstable,whichisrequiredfor
optimumfunctioning.
Diseasecanbeviewedasadisturbanceof
homeostasis.

17. Manifestationsofdiseases:
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1)Symptom:asubjectivecomplaint
2)Sign:amanifestationthatisnotedbyan
observer,doctorornurse,throughphysical
examination,e.g.anelevatedbodytemperature.
3) Laboratory finding:alterations found by
laboratory test, X-ray examination (routine or
CT), electrocardiogram(ECG),
ultrasonography, magnetic resonance imaging
(MRI), etc.

18. Sub-health
There is a situation, in which the person does
not show specific symptoms and signs of illness,
but lives a low-quality of life both physically
and mentally; this is called “sub-health”.
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19. Sub-health
75%
Health
5%
Disease
20%
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20. Senescence(Aging)
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Agingisanatural,lifelongprocess.There
isageneraldeclineinthestructureand
functionofthebodywithadvancingage,
resultinginadecreasedreservecapacityof
thevariousorgansystems.Thisresultsina
reductionofhomeostaticcapabilities,making
theolderadultmorevulnerabletostressors
suchasillness,surgery,medicaladministration,
andenvironmentalchanges.

21. 1-4Twoveryimportantconcepts
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1)PathologicalProcess
Aseriesofstructural,functionaland
metabolicchangesthatappearin
differentdiseases,e.g.
fever,inflammation,edema,etc.

22. Pathological Processand Disease
Disease Cause Site Fundamental
Pathological Process
PneumoniaPneumococcus LungFever, inflammation,
hypoxia, acid-base
disturbances, shock
DysenteryDysentery
bacilli
IntestineFever, inflammation,
water and electrolytes
disturbances, acid-base
disturbances, shock
Epidemic
meningitis
MeningococcusMeningesFever, inflammation,
DIC, shock
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23. 2)Syndrome
Asetofsignsandsymptomsthatoccur
togetherandarecharacteristicsofagroupof
diseasesoraspecificdisease,e.g.ARDS,AIDS
etc.
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24. Acute respiratory distress syndrome
(ARDS)
Shock, infection
acute and severe lung damage
pulmonary edema
lung volumes and compliance↓,
gas exchange impaired
tachypnea, labored breathing, cyanosis,
chest radiograph shows diffuse, symmetrical
interstitial and alveolar infiltration.
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25. 3. Etiology of Disease
Etiology is a science to study the factors
associated with or involved in initiation and
development of diseases. According to their
different roles in the development of diseases,
these pathogenic factors are classified into
cause of disease and conditional factors.
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26. Causesofdiseasesarethefactorsthatprovoke
orcausetheparticulardisease.Itdetermines
thecharacteristicsofthediseaseandis
absolutelynecessaryfordiseasetooccur.
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Conditionalfactorsarethefactorsthatdonot
causediseasedirectlybutratherinfluencethe
pathogenesisandthenaturaltimecourseofthe
disease.

27. Precipitating factors belong to conditional
factors that promote the development of
diseasesby enhancing the roles of cause of
diseases or susceptibility of the body to diseases.
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28. e.g. Infection, arrhythmias, pregnancy, water-
electrolytes and acid-base disturbances are
precipitating factors of heart failure
Tuberclebacillusisthecauseoftuberculosis.
Notallpeoplewhoinhaletheorganismwill
sufferfrompulmonarytuberculosis,which
occursinmalnutrition,overfatigueandlong-
termdepress.
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29. Controlling conditional factors is easier than
eliminating the causes.
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30. Causesofdiseases
ExtrinsicFactorsBiologicalagents
Physicalfactors
Chemicalfactors
Nutritionalfactors
Pathogenicfactors
IntrinsicFactorsGeneticfactors
Congenitalfactors
Immunologicalfactors
Psychologicalfactors
ConditionalfactorsBodycondition
(predisposingfactors)Naturecondition
Socialcondition
Precipitatingfactors
ofdiseases
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31. 3-2 Cause of Disease
1)Biologicalagentsbacteria,viruses,
2)Physicalfactors:traumaandfracture,heatstroke,frostbite.
3)Chemicalfactors
Corrosivechemicalssuchasstrongacidandbasescan
destroycellsatthesiteofcontact.Cell-injuriouschemicalsare
oftencalledtoxicsubstancesorpoison.Theyinducetissue
andcelldamagewhentheyenterthebodythroughcertain
pathwaysandreachasufficientamount.Thesecalled
intoxicationorpoisoning.Thetoxicsubstancesoftenacton
specificcellsororgans,e.g.COpoisoning.
Electricalinjuries
Radiationinjuries
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32. 4)Nutritionalfactors
Excesses:highlipidsandcarbohydrates
dietobesity,atherosclerosis,diabetes
Deficiencies:lackofcertainelementsindiet
(1)VitaminB:beriberi
(2)VitaminA:nightblindness
(3)VitaminC:scurvy
(4)VitaminD:rickets
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33. 3-2-2IntrinsicFactors
1)Geneticfactors
Alteredgeneticmaterialpassedfromparenttooffspring
iscalledgeneticfactors,whichisclassifiedintothree
groups.
Geneticdisorders
Chromosomedisorders:thedefectresultsfrom
numericalandstructuralabnormalitiesofchromosome.
Single-genedisorders:thedefectiscausedbyasingle
defectiveormutantgene.
Multifactorialinheritance:polygeneticdisorder.
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34. Common Examples of Genetic Disorders
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Disorder ClassificationGenetics
Huntington
disease
Single-gene disorderAutosomal
dominant
Cystic fibrosisSingle-gene disorderAutosomal
dominant
Hypophosphatemia
(vitamin D-
resistant rickets)
Single-gene disorderX-lined dominant
Hemophilia Single-gene disorderX-lined dominant
Down syndrome Chromosome disorderTrisomy 21
Turner syndromeChromosome disorder45, X

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Down syndrome
47, +21

36. Inheriteddisease:diseasecausedbyaltered
geneticmaterial,eithersinglegenemutationor
chromosomeaberrations.e.g.colorblindness,
Albinism,Downsyndrome.
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37. 38
Disorder of multifactorialinheritance
result from a combination of the multiple gene
variations with environmental factors. Therefore
the disease on phenotype are not hereditary, but
these diseases dohave a genetic background
(genetic susceptibility), such as congenital heart
disease, cleft lip, coronary artery disease and
hypertension.

38. Geneticpredisposition(geneticsusceptibility):
astateofbodyfavorabletoorshowinga
tendencytocertaindiseasesbecauseof
polygeneticabnormalities.
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39. 2)Congenitalfactors
Environmentfactorsthatoccurredduring
embryonicorfetaldevelopmentarecalled
congenitalfactors,includingthephysiologic
statusofthemother(maternaldisease)and
teratogenicagents(infectionsordrugstaken
duringpregnancy),whichactsontheembryoor
fetus,causingabnormalitiesinformorfunction.
Diseasescausedbycongenitalfactors
calledcongenitaldisease.e.g.congenitalsyphilis.
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40. 3)Immunologicalfactors
Althoughtheimmuneresponseisanormal
protectivemechanism,itmaycausediseasewhile
theresponseisdeficient(immunodeficiency
disease),inappropriatelystrong(allergyor
hypersensitivity----penicillin),ormisdirected
(autoimmunedisease----ankylosingspondylitis).
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41. 4)Psychologicalfactors
Anxiety,strongorpersistantpsychological
stimulationorstressmayleadtomentalillness
andmayberelatedtosomediseasesuchas
hypertension,pepticulcer(duodenalulcer),and
coronaryheartdisease.
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42. 3-3 Conditional Factors
1)Body’scondition:age,sex,race;physical
training,mentalcondition,fatigue,smoking,
lifestyle.
2)Naturecondition:weatherconditionand
geographicalenvironmentinfluencesome
epidemicaldiseases.
3)Socialcondition:laborandhygiene
conditions----occupationaldiseases,social
lifeevents----person’smoodandlifepattern.
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43. Cause
Conditional factorsBody
Disease
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44. Causesofdiseases
ExtrinsicFactorsBiologicalagents
Physicalfactors
Chemicalfactors
Nutritionalfactors
Pathogenicfactors
IntrinsicFactorsGeneticfactors
Congenitalfactors
Immunologicalfactors
Psychologicalfactors
ConditionalfactorsBodycondition
(predisposingfactors)Naturecondition
Socialcondition
Precipitatingfactors
ofdiseases
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45. 4. Pathogenesis of disease
Pathogenesis of disease refers tothe rules and
mechanisms underlying the development or
evolution of the diseases.
4-1 General rules for pathogenesis of disease
1) Disruption of homeostasis
If homeostasis is disrupted by a variety of
harmful agents, the body cannot function
optimally, and illness may occur.
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46. 2) Process of damage and anti-damage
Damage can induce body’s anti-damage
responses. The development of a disease
depends on the strength of damage and anti-
damage factors.
Too much anti-damage process will cause new
injury to the body (SIRS----MODS)
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47. 3) Reversal role of cause and result
The cause of the disease lead to a result, which can
be another cause of the disease in the evolution
process.
(Cause) (Result)
Chronic hypoxia erythrocyte￪ polycythemia
(Cause) (Result)
blood viscosity ￪ thrombus
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48. Mechanical trauma Hemorrhage
Cardiac output↓↓
Returned blood
volume↓
Blood pressure↓↓
Microcirculation
congestion
Sympathetic nerve excite
Capillary open Vasoconstriction
Hypoxia in tissure
vicious cycle
Maintain BP
Heart rate ↑
Contractility ↑
beneficial cycle
Recovery
(Cause) (Result)
(Cause)
(Result)
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49. 4)Correlationbetweensystemicandlocal
regulations
Local alterations can affect the whole body
through neural and humoralregulation, and
the systemic functional statues can in turn
affect the development of local damages via
the same regulating strategies.
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50. e.g. a severe furuncle congestion and edema (local)
fever, chill and WBC ￪(systemic)
e.g. a recurrent furuncle may represent systemic metabolic
disorder caused by diabetes.
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51. 5. Outcome of Diseases
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Recovery
Death
Complete recovery
Incomplete recovery

52. 5-1Completerecovery
Thealterationsofthefunction,metabolism
andstructureofthebody,whichappearedin
disease,areperfectlyrestored.
Thesignsandsymptomsofthediseaseare
disappearentirely.
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53. 5-2Incompleterecovery
Themainsymptomsareabsent.
Somepathologicalchangesarestillpresentinthebody.
Itisbroughtaboutbythecompensatoryresponseto
maintainarelativelynormallifeactivity.
--e.g.Heartdiseasepatients
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54. 5-3Death
5-3-1Definition:
Irreversiblecessationofthefunctionofthebodyasa
whole.
Contemporaryconceptofdeathisbraindeath.
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55. 5-3-3Definitionofbraindeath
Prolongedirreversiblecessationofallbrain
functions,includingthebrainstem.
5-3-4DiagnosisofDeath
Thebasesfordemonstratingbraindeath
aretheabsenceofbrainstemreflexes,absence
ofcorticalactivityanddemonstrationof
irreversibilityofthestate.
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56. Criteria indicating brain death
◆Irreversible coma and cerebral
unresponsiveness:completelackofcerebral
responsetoanyformofexternalexcitation.
◆Absence of all brain stem reflexes: It
includes the absences of pupilaryreflex,
corneal reflex, cough reflex and swallowing
reflex.
◆Cessation of spontaneous respiration
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57. ◆Absence of any electrical activity of brain
indicated by EEG (electroencephalogram)
for at least 6 hours.
◆Cessation of cerebral circulation
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58. Summary
1.Diseaseisanabnormallifeprocessinwhich
thebody’shomeostasisisdisruptedbythe
interactionsofcertainpathogenicfactorand
thebody.Intrinsicchangesofdiseasesare
alterationsinstructures,functionsand
metabolismsofthebody.
2.Asetofstructural,functionalandmetabolic
changesthatoccurtogetherindifferentdisease
iscalledpathologicprocess.
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59. 3.Pathologicfactorsincludecauseofdisease
thatprovokediseaseanddetermineits
characteristicsandconditionalfactorsthat
participateinandinfluencethepathogenesisof
disease.Conditionalfactorsthatpromotethe
pathogenesisofdiseasearecalledprecipitating
factors.
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60. 4.Irreversiblecessationofallbrainfunctions,
includingthebrainstemiscalledbraindeath.
Thebasesfordetermineitareabsenceof
corticalactivity,absenceofbrainstemreflexes,
anddemonstrationofirreversibilityofthestate.
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