Disease Classification Overview

Study Notes

Disease Classification

Diseases are broadly categorized based on factors like etiology (cause), pathogenesis (development), and clinical presentation.
Infectious diseases are caused by pathogens like bacteria, viruses, fungi, or parasites.
Non-infectious diseases arise from genetic predisposition, environmental exposure, or lifestyle choices. Examples include cancer, cardiovascular disease, and diabetes.
Congenital diseases are present at birth, often due to genetic abnormalities or environmental influences during gestation.
Degenerative diseases involve progressive tissue or organ deterioration, such as Alzheimer's disease.
Mental illnesses affect thoughts, emotions, and behaviors; categorized by symptoms and characteristics.
Chronic diseases are long-lasting, needing ongoing management.
Acute diseases have rapid onset with intense symptoms, and short duration.

Pathology Basics

Pathology studies disease through structural and functional changes in tissues and organs.
Pathologists use microscopy, immunohistochemistry, and molecular biology for disease diagnosis and understanding.
Cellular changes are often central to disease pathology.
Atrophy is decreased cell size and function.
Hypertrophy is increased cell size and function.
Hyperplasia means increased cell number.
Dysplasia shows abnormal cell size, shape, and organization.
Metaplasia is a reversible cell type replacement.
Neoplasia (tumor formation) involves uncontrolled growth, potentially leading to malignant tumors.
Inflammation is a protective body response; prolonged or severe inflammation can damage tissues. Inflammation recruits immune cells and releases inflammatory mediators.
Apoptosis (programmed cell death) is crucial for normal tissue development and maintenance.
Necrosis is premature cell death due to injury (e.g., pathogens, toxins, trauma), often causing inflammation.
Cellular injury sources include:
- Hypoxia: Reduced oxygen supply.
- Ischemia: Reduced blood flow.
- Physical agents: Trauma, heat, radiation.
- Chemical agents: Poisons, toxins, heavy metals.
- Infectious agents: Viruses, bacteria, fungi, parasites.
- Immunologic reactions: Autoimmune diseases, allergies.
- Nutritional imbalances: Nutrient deficiencies or excesses.
Cellular adaptations are reversible adjustments to stress, allowing survival but potentially compromising function.
Cellular accumulations happen when cells cannot digest or remove substances, e.g., lipid accumulation.
Cellular aging is the normal, natural decline in cellular function throughout a lifespan.

Description

Explore the various classifications of diseases based on etiology, pathogenesis, and clinical presentation. This quiz covers infectious, non-infectious, congenital, degenerative, mental illnesses, and chronic diseases. Test your knowledge on the factors that contribute to these health conditions.