Untitled Quiz

Pathology - Study of Disease

• Pathology is the study of disease.
• Etiology involves causes, modifying factors, genetic predisposition, and environmental factors.
• Pathogenesis describes the steps of developing a disease.
• Pathology identifies gross morphological changes in cells, tissues, and body fluids.

Introduction to Pathology

• Pathology is the study of disease.

Classification of Disease

• The classification of diseases aids in statistics regarding morbidity (illness) and mortality (causes of death).

Topographic Classification

• Diseases are categorized by body region (e.g., gastrointestinal, vascular).
• Specialists often focus on specific body regions, for example, vascular surgeons.

Anatomic Classification

• Diseases are categorized by the specific organ or tissue affected.
• Specializations, such as cardiology, are often restricted to a single organ.

Physiological Classification

• Diseases are categorized by the functional disturbances caused by a specific disorder.
• Respiratory diseases affect air intake and carbon dioxide exchange.
• Metabolic diseases involve disturbances in the body's chemical processes.

Pathological Classification

• Pathological classifications consider the nature of the disease process.
• Examples include neoplastic and inflammatory diseases, specifically cancers and their impact on beings.

Etiologic Classification

• Etiologic classification focuses on the cause of a disease.
• This is important when identifying diseases like staphylococcal, rickettsial, and fungal diseases.
• Diseases may affect specific organs/systems like the kidneys, liver, meninges, skin, and lungs.
• Sexually transmitted diseases (STD's) fall into this category

Epidemiological Classification

• Epidemiological classification focuses on the incidence and distribution of diseases in a population.
• Helps with controlling the spread of disease and understanding its origins.

Cellular Responses

• Cells actively participate and change structure and function.
• Cells maintain homeostasis (steady state)
• Cells adapt when facing physiologic or pathological stress.

Cellular Response Stages

• Two adaptation types exist: physiological and pathological.
• Adaptation responses include hypertrophy, hyperplasia, atrophy, and metaplasia.

Cellular Injury

• Normal cells can become injured due to stress.
• Injury can be reversible or irreversible which can lead to cell death.
• Irreversible injury leads to cell death via necrosis and apoptosis.

Hypertrophy

• Hypertrophy is an increase in cell size, resulting in organ enlargement.
• Physiologic hypertrophy is hormone-driven growth, for example, due to pregnancy.
• Pathologic hypertrophy is abnormal, for example, due to cardiac muscle enlargement.
• Hypertrophy mechanism is triggered by a mix of mechanical factors (e.g., stretch) and trophic factors (e.g., growth factors).

Hyperplasia

• Hyperplasia is an increase in cell number.
• Physiological hyperplasia is controlled hormone-driven growth, for example, in puberty.
• Pathologic hyperplasia is potentially problematic (e.g, uncontrolled growth due to hormones).

Atrophy

• Atrophy is a decrease in cell size or cell mass.
• Causes are varied, including disease or injury, loss of innervation, diminished blood supply, or aging-related factors.

Metaplasia

• A reversible change in which one adult cell type replaces another.
• Stem cells reprogram (or differentiation of adult cells)
• Often seen in smokers due to squamous epithelium replacing columnar epithelium.
• Can increase the risk of cancer and other diseases in specific locations.