Introduction to PathologyDr.H.Zahawi,FRC.Path

Study of Medicine & Disease

• Greek : Pathos Logus

• Pathology is the study of suffering

• Disease is Dis-ease

• Egyptian,Arabs, Greece, Rome, middle ages

• Scientific Revolution 16th.-17th.

What is Pathology ?

• Study of disease by scientific methods• Individual’s reaction to injury & its effect on body• Effect recognized by structural &functional

changes PATHOPHYSIOLOGY• Result is either compensated , decompensated

or causes death .• Links basic science to clinical practice

History of Pathology

Influence of magic or supernatural

Deficiency or excess body fluids Hippocrates ‘Father of Medicine’

Postmortems & gross pathology ( 300BC) Van Leeuwenhoek ‘microscope’ 17th.century Study of cells Rudolf Virchow ‘Father of Pathology’

Anisim

Humors

Morbid anatomy

Cellular path.

Microscopes 17th.-19th.century

Pathology in the 21st.century

• Many new techniques

Electron Microscopy

Genetics

• KNOW THE NORMAL BEFORE THE ABNORMAL

Subcellular

Molecular

Branches of Pathology

• Anatomic pathology : Study of tissues or cells - Postmortem Examination ( autopsy ) - Forensic Pathology - Surgically removed specimens - Cytology of smears, Fine Needle Aspiration• Clinical pathology : - Clinical chemistry - Hematology - Microbiology - Immunology - Genetics

How Pathology is taught• General pathology : studies mechanism & the

characteristics of principle types of disease processes e.g.

- cell injury

- inflammation

- neoplasia• Systemic pathology : studies specific diseases in

specific organ systems. e.g.

- lung abscess

- breast cancer

Steps in study of diseases• Epidemiological aspects• Etiology: identifiable cause of disease - Intrinsic : genetic

- Extrinsic : acquired

- Idiopathic

• Pathogenesis : Sequence of events in the response of cells& tissues to the etiological agent, from the initial stimulus to the final expression of disease. This response can be studied morphologically, biochemical, immunologically or at molecular level.

• Pathological & clinical features including biochemical tests, radiological findings

INTEGRATE ALL INFORMATION !!!!!

• Complications & sequelae : Events taken during the disease process that may impair full recovery

• Treatment

• Prognosis : A forecast as to the probable result of an attack of

disease and the prospect of recovery.

To aid diagnosis , study morphology :

• Samples for study include cells, biopsy or whole

organ :

- Gross or macroscopic appearance

- Histological or microscopic appearance

- Electron microscopy or ultrastructure

• Genetic & molecular methods may aid diagnosis

Sample case A 60 year old woman with a lump in the

neck of 6 months duration. Patient has fever & raised BMR ( ESR) On examination she also had enlarged inguinal lymph nodes. Further investigations were within normal

• Biopsy was taken

i.e. tissue removed for microscopical exam

Follicular Lymphoma

• Genetic Studies :

Translocation t18: 14

• Treatment : Chemotherapy

• Prognosis : Good

Basal Cell Carcinoma

Opened uterus with leiomyomas

Gross Microscopy

Gross ????

Electron microscopy useful in some cases

CONCLUSION :

• PATHOLOGY AIDS IN DIAGNOSIS& MANAGEMENT OF DISEASE PROCESSES

• PATHOLOGY IS THE BASES OF MEDICINE