This document provides an overview of pathology, defining key terminology like patient, lesion, morphology, and aetiology. It explains that pathology is the study of structural, biochemical, and functional changes in cells, tissues, and organs that underlie disease. Pathology examines four aspects of disease: etiology, pathogenesis, morphologic changes, and functional derangements. Pathology is broadly divided into general pathology, which deals with basic disease mechanisms, and systemic pathology, which covers diseases as they occur in specific organ systems. Understanding pathology is essential for doctors to properly diagnose and treat patients.

1. How we overcome pathology

2. 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.
Aetiology: is the cause of the disease.
Pathogenesis: is the mechanism by which the
disease is produced.
Physical signs: are the functional implications
of the disease felt by the patient.

3. HEALTH AND DISEASE:
Health: complete physical, mental and social
wellbeing, 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.

4. Most of these topics represent the major
categories of diseases that can occur in
different organ systems. For example,
acute inflammation can occur in different
organs but wherever it occurs its
mechanism is the same. That is, an acute
inflammation in the skin has the same
mechanisms & features as an acute
inflammation of the meninges.

5. 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. Diseases may, in turn, be defined as an
abnormal variation in structure or function of
any part of the body. Pathology gives
explanations of a disease by studying the
following four aspects of the disease.
1. Etiology: the cause of the disease.
2. Pathogenesis: the cause operates to
produce the pathological and clinical
manifestations.

7. 3. Morphologic changes: The morphologic
changes refer to the structural alterations in
cells or tissues that occur following the
pathogenetic mechanisms
4. Functional derangements and clinical
significance: The morphologic changes in the
organ influence the normal function of the
organ. By doing so, they determine the clinical
features (symptoms and signs), course, and
prognosis of the disease.

8. The knowledge and understanding of pathology
is essential for all would be doctors and general
practitioners. Unless 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.

9. Pathology is broadly divided into two
categories:
1. General pathology: deals with general principle
of disease, covers the basic mechanisms of
diseases, E.g. inflammation, cancer, ageing, Cell
injury, Healing, Hemodynamic disorders, Genetic
diseases, Immunopathology, Metabolic diseases,
& Selected infectious diseases.

10. The same principle applies to the
other topics covered in general
pathology. Therefore, general
pathology can be applied this
knowledge to diseases in the various
organ systems.

11. Hence, the general pathology
knowledge will facilitate the
understanding of systemic diseases
(Systemic Pathology).
Therefore, the whole purpose of
general pathology is to understand
systemic diseases – i.e. Systemic
Pathology.

12. 2. Systemic pathology:
covers diseases as they occur in
each organ system, Study of disease
pertaining to the specific organs and
body systems.

13. It is further divided in to following
branches:
1. HISTOPATHOLOGY:
a. gross or macroscopic examination
b. microscopic examination.
It is further divided in to:
a. Surgical pathology
b. Forensic pathology i.e .autopsy

14. 2. CYTOPATHOLOGY:
a. Exfoliative cytology. b. FNAC
3. HAEMATOLOGY: deals with the disease of
blood and blood related components.
4. MICROBIOLOGY: deals with the study of
microorganisms.
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.

15. 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.