PathophysiologyPathophysiology

DR . Ahmed DR . Ahmed ZakiZaki Abdullah AlAbdullah Al‐‐AniAni

Professor of MedicineProfessor of Medicine

The Hashemite Kingdom Of JordanThe Hashemite Kingdom Of Jordan

Lecture OneLecture One

Introduction to PathophysiologyIntroduction to Pathophysiology

Levels of OrganizationLevels of OrganizationCh i l• Chemical

• Cellular

• Tissue• Tissue

• Organs

• System Level• System Level

• Organismic Level

Principles of Human Anatomy and Physiology, 11e 3

LEVELS OF ORGANIZATIONLEVELS OF ORGANIZATION

• The human body consists of several levels of structural organization 

• The chemical level– atoms, the smallest units of matter that participate in , p pchemical reactions, and molecules, two or more atoms joined together.

C ll• Cells– the basic structural and functional units of an organism.Ti• Tissues– groups of similarly specialized cells and the substances surrounding them that usually arise from a common originsurrounding them that usually arise from a common origin and perform certain special functions.

Principles of Human Anatomy and Physiology, 11e

4

LEVELS OF ORGANIZATIONLEVELS OF ORGANIZATION

• Tissues– groups of similarly specialized cells and the substances g p y psurrounding them that usually arise from a common origin and perform certain special functions.

O• Organs– structures of definite form that are composed of two or more different tissues and have specific functionsmore different tissues and have specific functions.

• Systemsrelated organs that have a common function– related organs that have a common function.

• The human organismll ti f t t ll d f ti ll i t t d– a collection of structurally and functionally integrated 

systems; any living individual.

Principles of Human Anatomy and Physiology, 11e

5

LEVELS OF ORGANIZATIONLEVELS OF ORGANIZATION

• The systems of the human body are the i t t k l t l lintegumentary, skeletal, muscular, nervous, endocrine, cardiovascular, lymphatic, , , y p ,respiratory, urinary, digestive, and reproductivereproductive

Principles of Human Anatomy and Physiology, 11e

6

LEVELS OF ORGANIZATIONLEVELS OF ORGANIZATION

• The human body consists of several levels of structural organization 

• The chemical level– atoms, the smallest units of matter that participate in , p pchemical reactions, and molecules, two or more atoms joined together.

C ll• Cells– the basic structural and functional units of an organism.Ti• Tissues– groups of similarly specialized cells and the substances surrounding them that usually arise from a common originsurrounding them that usually arise from a common origin and perform certain special functions.

Principles of Human Anatomy and Physiology, 11e

7

Health and Disease

Disease ‐ Deviation from normal (physical, mental and social).

Homeostasis‐ Stable internal environment (BP, temp, fluids, electrolytes) values are 

represented in ranges that can be adjusted for additional factors like 

age and activity level.

T d i P th h i lTerms used in Pathophysiology

Pathophysiology ‐ study of functional or physiological changes in the body         resulting from disease process, both gross changes  and g p , g gcellular changes.

Pathology ‐ lab study of cell and tissue changes associated with diseaseBiopsy ‐ Surgical specimensBiopsy ‐ Surgical specimens.Diagnosis ‐ Identification of a disease through the evaluation of signs 

and symptoms, lab tests and other tools.Etiology ‐ The causative factors of a disease (congenital geneticEtiology ‐ The causative factors of a disease (congenital, genetic, 

microorganisms, metabolic dysfunction, burns, nutritional deficiency).

Idiopathic ‐ Cause unknownIdiopathic ‐ Cause unknown.Iatrogenic ‐Caused by an error in treatment or procedure  bladder  

infections after a cath insertion, bone marrow damage from i ti f dprescription  of  a drug

Predisposing factors -Tendencies that promote development of a disease in an individual.

-Indicates high risk, not certain development-Age, gender, diet, occupational exposure, genetic

Prevention - Vaccine, dietary and lifestyle modifications e.g (stop smoking)

Terms used to describe the characteristics of aTerms used to describe the characteristics of a particular disease

Pathogenesis‐ Development of a disease or sequence of events involved in tissue changes related to a disease process.

Acute sudden short term illness with marked signsAcute ‐sudden short term illness with marked signs.Chronic ‐milder condition but persists for a long time.Sub clinical ‐ Pathological change occurs but no obvious manifestations 

are exhibited by the patientLatent‐ “silent”, no clinical signs (incubation period).Prodromal ‐ The time in early development of the disease where the y p

patient is aware of some changes but the signs are nonspecific e.g ‐fatigue, loss of appetite.

Manifestation ‐ Clinical evidence or effects of a diseaseManifestation ‐ Clinical evidence or effects of a disease.Local ‐ Found at the site of the problem like swelling.Systemic ‐ A general indicator of  illness like fever.Signs ‐ Objective indications of diseases like fever or rash

Symptoms ‐ Subjective feelings like pain or nausea.

Lesion ‐ Specific local tissue change .

‐ can be either microscopic changes or things like blisters

Syndrome ‐ A collection of signs and symptoms that occur together in response to a certain conditionresponse to a certain condition.

Diagnostic tests ‐ lab tests that assist in diagnosing a disease.

Remission ‐manifestations of disease subside.

Exacerbations ‐manifestations of a disease increase.

Precipitating factor ‐ something that triggers an acute episode.

Complications‐ additional problems that arise after the original disease  begins.

Therapy/therapeutic interventions ‐Measures that promote recovery or slow disease progress e g surgeryslow disease progress e.g surgery, drugs, behavioral

Sequelae ‐ Potential unwanted outcomes of condition.qConvalescence ‐ Period of recovery and return to normal state.Prognosis ‐ Probability for recovery.Morbidity ‐ Disease rates within a group.Mortality ‐ Relative number of deaths resulting from a particular diseaseEpidemiology The science of tracking pattern and occurrence of diseasesEpidemiology ‐ The science of tracking pattern and occurrence of diseases

‐ infectious diseases, flu vaccine.Epidemics ‐Many cases of infectious diseases within a given area.Epidemics Many cases of infectious diseases within a given area.Pandemic ‐ High number of cases over several areas (often worldwide).

Incidence ‐ # of new cases within a given stated time periodCommunicable disease ‐ Infections that can be spread from one person 

t thto another.

Notifiable/Reportable diseases ‐Must be reported to authorities

‐intended to protect public healthintended to protect public health

‐measles, AIDS.

Autopsy ‐ An exam of the body after death by a pathologist, gross and 

microscopic  exam of the tissues , organs, and fluids.

Terms used for some of the common changes in cells

Atrophy ‐ Decrease in size of cells which leads to a decrease in tissue mass

‐muscles in a cast.

Hypertrophy ‐ Increase in the size of cells which leads to an  increase 

in tissue mass e.g exercise.

l i i h b f ll l di i i iHyperplasia ‐ Increase in the number of cells leading to an increase in tissue mass

‐Hormonal changes.

Metaplasia ‐One mature cell type is replaced by another mature cell typeMetaplasia ‐One mature cell type is replaced by another mature cell type

‐Smokers lungs.

Dysphasia ‐ Tissue in which cells vary in shape and size 

‐Chronic irritation, infection.  

‐ Precancerous.

Anaplasia ‐ cells that are undifferentiated and have variable nuclei and  structure and 

numerous mitotic figures .Malignancy/cancer, basis for grading a tumor.

Neoplasm ‐ New growth/ tumorNeoplasm ‐ New growth/ tumor.

Benign ‐ Don’t spread, not life threatening.

Malignant ‐ cancerg

Cell damage and Necrosis Ways of injuring cells in the g y j gbody

Ischemia ‐ Deficit of oxygen to cells.Hypoxia ‐ Decrease in oxygen in tissue.

I f i h ATP di d l d‐ Interferes with ATP, stops sodium pumps and leads to rupture of cell.

Physical agents ‐ Heat cold, radiation damages DNA and changes bloodPhysical agents  Heat cold, radiation damages DNA and changes blood supply.

Mechanical damage ‐ pressure and tearing.  Ch i l i f i bChemical toxins or foreign substancesExogenous ‐ outside of the bodyEndogenous ‐ inside of the bodyEndogenous  inside of the bodyMicroorganisms‐bacterial, viruses, parasites.Abnormal metabolites accumulating in cells.N i i l d fi i iNutritional deficiencies.Imbalance of food and electrolytes.

C ll D (2 )Cell Damage (2 stages)

1 .Initial       ‐ Alteration in the metabolic reaction leading to loss of function

‐ Leads to morphological/structural changes that lead to cell p g / gdeath by rupture.

2.Lysis ‐ Dissolution‐releasing  lysosomal enzymes which leads i fl i hi h l d h d i f b llto inflammation which leads to the damaging of nearby cells.

‐Necrosis ‐ dead cells liquefy under the presence of certain cell enzymes.

‐Infarction ‐ an area of dead cells resulting from lack of oxygen.Infarction  an area of dead cells resulting from lack of oxygen.

‐Gangrene ‐ an area of necrotic tissue that has been invaded by bacteria.

Thank You...Thank You...