Pathology is the study of disease and disease processes. Some key figures in the development of pathology include Rudolf Virchow (Father of Pathology), Marie François Xavier Bichat (Father of Histology), and Anton van Leeuwenhoek (Father of Microscopy). The goals of pathology for students are to understand the relationship between pathologic changes and clinical manifestations, take clinical histories, develop superficial diagnoses, and communicate findings. Pathology seeks to describe the effects, progression, and consequences of disease as well as determine the causes and underlying mechanisms. Key aspects of understanding a disease include its definition, epidemiology, etiology, pathogenesis, morphology, functional consequences, management, prognosis, and prevention.

1. WELCOME TO
PATHOLOGY
-An introduction
Dr. Saugat Chapagain

3. Meet the Fathers
– FATHER OF PATHOLOGY: RUDOLF VIRCHOW
– FATHER OF HISTOLOGY: MARIE FRANÇOIS XAVIER BICHAT
– FATHER OF MICROSCOPY: ANTON VAN LEEUWENHOEK
– FATHER OF MICROBIOLOGY: LOUIS PASTEUR

4. Goals of Pathology for a Student
– Be able to understand and analyze the relationship between pathologic changes
and clinical manifestations
– Be able to take a clinical history somewhat similar to physicians / surgeons
– Be able to develop a superficial diagnosis
– Be able to communicate with professionals and patients

5. INTRODUCTION TO
PATHOLOGY
– The word PATHOLOGY is derived from two Greek words-
–‘Pathos’ meaning suffering and
–‘logos’ meaning study.
Pathology is a study of the structural, biochemical and functional
changes in cells, tissues and organs that underlie disease.

6. –The knowledge and understanding of pathology is essential for all would be
doctors and general practitioners.
– They know the causes and mechanism of disease and understand the language
spoken by the pathologists in the form of laboratory reports.
–They would not be able to institute appropriate treatment or suggest preventive
measures to the patient.

7. – Study of disease or suffering
– Describes the effects, progress and consequence of the disease
– Attempts to determine the cause (etiology) and underlying mechanisms
(pathogenesis)
– Since the disease effect the structural and functional components of cell, tissue
or organ of the body, it is the "scientific study of the molecular, cellular, tissue,
or organ system response to injurious agents."

8. Pathology answers the
questions:
– How the disease cause the observed system?
– Ideally, it explains the steps by which the etiological risk factors lead to
malfunctioning
– It then describes the changes caused in the body function resulting from the
disease and the body’s response to this

9. Pathophysiology
• Relates the effects of disease to the disruption of normal physiological
functions, e.g. The pathophysiology of essential hypertension involves a
raised peripheral vascular resistance and possibly an expansion of
intravascular fluid volume
• Immunopathology- Study of immunological processes involved in the
development of autoimmune disease

10. HEALTH AND DISEASE
– Health- complete physical, mental and social well being, not merely an absence
of disease.
– Disease- is expression of discomfort due to structural or functional abnormality.
– Illness- is the reaction of individual to disease in the form of symptoms.

11. A disease can fall in one of the
following categories:
– Developmental
– Inflammatory
– Neoplastic
– Degenerative

12. What should we Know About A
Disease
• Definition
• Epidemiology- where &when?
• Etiology- what is the cause?
• Pathogenisis- evolution of dis.
• Morphology- structural changes PATHOLOGY
• Functional consequences
• Management
• Prognosis
• Prevention

13. Morphology: Structural Changes
– Structural changes in disease.
– Tumor in a cancer.
– Ulcer in an infection.
– Atrophy in dementia.
– Gross & Microscopic.

15. TERMINOLOGY IN
PATHOLOGY
 Patient- is a person affected by the disease.
 Lesion- is characteristic changes in tissue and cells.
 Morphology- is examination of diseased tissue.
 Etiology- is the cause of the disease.
 Pathogenesis- is the mechanism by which the disease is produced.

16. • Symptoms- subjective noticed by patient and either reported or elicited on
questioning
• Signs- objective and noticed by the clinician on examination, although
occasionally may be noticed by the patient
• Pathognomonic- Many disease have such consistent presentation to be
almost diagnostic, e.g., a spiking fever, stiff neck and photophobia in
meningitis; such definitive features are called pathognomonic
• Syndrome- A well defined group of clinical features that commonly occur
together ,e.g., proteinuria, hypoproteinemia and edema together ‘nephrotic
synd.’

17. • Prognosis- the probably outcome of a disease in a living individual (cure,
morbidity or mortality)
• Acute illness- Starts suddenly (acute onset) and resolves either of its own
accord or following treatment
• Chronic disease- starts insidiously and continues for a long time, possibly
lifelong
• Progressive disease- if a chronic disease tend to deteriorate steadily, it is called
progressive disease

18. SUBDIVISION OF PATHOLOGY
• General pathology-deals with general principle of disease.
E.g inflammation ,cancer, ageing.
• Systemic pathology-Study of disease pertaining to the specific organs
and body systems.

19. Systemic pathology
1. HISTOPATHOLOGY
1. gross or macroscopic examination
2. microscopic examination
It is further divided in to
1. Surgical pathology
2. b.Forensic pathology i.e. autopsy
2. CYTOPATHOLOGY
1.Exfoliative cytology
2.FNAC
3. HAEMATOLOGY- deals with the disease of blood and blood related components.
4. MICROBIOLOGY- deals with the study of microorganisms.

20. 5. CHEMICAL PATHOLOGY- analysis of biochemical constituent of blood, urine,
semen, CSF etc.
6. IMMUNOLOGY- detection of abnormalities in the immune system of the body.
7. EXPERIMENTAL PATHOLOGY - study of disease in experimental animal.
8. GEOGRAPHIC PATHOLOGY- study of diseases in populations in different parts of
world.
9. MEDICAL GENETICS- it deals with the relationship between heredity and disease.
10. MOLECULAR PATHOLOGY- Detection and diagnosis of abnormalities at the level of
DNA