Introduction to Pathology

Introduction to Pathology

• Pathology is the branch of medicine focused on the study of disease, its causes, mechanisms, and effects on the body.
• It involves examining tissue, blood, and other bodily fluids to understand disease processes.
• Pathology aims to understand the nature of diseases and how they affect the body.
• It considers the structural and functional changes diseases cause at the cellular, tissue, and organ levels.

URS (University of Rizal System) Information

• Vision: The leading University in human resource development, knowledge generation, and environmental stewardship.
• Mission: URS is dedicated to nurturing and producing competent, upright graduates and empowering the community through relevant, sustainable higher professional and technical instruction, research, extension and production services.
• Core Values: Responsiveness, Integrity, Service, Excellence, and Social Responsibility.
• Quality Policy: Commits to providing excellent products and services to ensure total stakeholder satisfaction in instruction, research, extension, production, and administrative support. Contributes to improving the Quality Management System processes to meet all relevant requirements.

Grading System

• Lecture: 60% - class standing, 30% - quizzes, 20% - recitation, 10% - project.
• Major Examinations: 40%.
• Total: 100%

House Rules

• 30-minute grace period.
• Attendance is mandatory.
• Phones must be on silent mode.
• Daily uniform is required.

Requirements

• 1¼ index card, white
• Name: (Last Name, Given Name, Middle Name)
• Year and Program
• Complete address
• Birthday
• Contact number
• 1x1 clear photograph (upper right of card)

Learning Objectives

• Understand and define the concept and nature of pathology.
• Identify and outline the mechanisms and nature of diseases.
• Relate and discuss the causes and effects of diseases.
• Understand the relationship between the cell cycle and carcinogenesis.
• Understand and apply disease prevention and promotion of good health.

What is Pathology? (Detailed)

• Pathology originates from the Greek words "pathos" (suffering or disease) and "logos" (study or discourse).
• Pathology is the branch of medicine focusing on the study of disease; its causes, mechanisms, effects and processes.
• Tissue, blood, and other body fluids are examined to understand disease processes.
• The goal is to examine structural and functional changes at the cellular, tissue, and organ levels that are caused by the disease.

Importance of Pathology

• Provides critical insights into:
  • Diagnosis: Pathologists analyze biological samples (tissue, blood, fluids) to identify disease presence. Crucial for diagnosing conditions like infections, cancer, and autoimmune disorders.
  • Prognosis: Assess disease severity and predict future course. Examples include staging and grading cancer for patient management.
  • Treatment decisions: Pathology study results help doctors select appropriate medical treatments (e.g., surgery, chemotherapy, or targeted therapies).
  • Prevention and Screening: Pathologists develop disease detection strategies. Example: early disease detection for improved patient outcomes.

Divisions of Pathology

• Anatomical Pathology: Studies tissue samples to understand structural changes due to disease (e.g., biopsies, autopsies).
  • Subspecialties: Histopathology, Cytopathology, Forensic Pathology.
• Clinical Pathology: Focuses on laboratory medicine and diagnostic tests for blood, urine, and other body fluids.
  • Subspecialties: Hematology, Microbiology, Biochemistry, and Molecular Diagnostics.
• Other Branches: Forensic Pathology (causes of death), Veterinary Pathology (animal diseases), and Research Pathology (investigating disease mechanisms).

Understanding Disease Mechanisms (Pathogenesis)

• Pathogenesis: Process by which a disease develops and progresses.
• Key Factors: Genetic factors (DNA mutations), environmental factors (toxins or pathogens), immunological factors (immune system dysfunction). Cellular factors (e.g. cellular injury).
• The chain of events from the initial causative agent to the manifestation of symptoms.

Key Processes in Pathology

• Inflammation: Protective response to injury or infection, can be chronic.
• Cell Death: Apoptosis (programmed) and necrosis (uncontrolled).
• Neoplasia: Abnormal cell growth—leading to benign or malignant tumors (e.g., cancer).
• Infection: Pathogens (bacteria, viruses, fungi, parasites) invade and cause diseases.
• Immunopathology: Diseases caused by the immune system attacking the body's own tissues (e.g., autoimmune diseases).

The Pathologist's Role in Medicine

• Clinical Pathologists: Focus on laboratory tests and results interpretation to diagnose diseases. Uses samples like blood, urine, etc.
• Anatomical Pathologists: Examine tissues and organs (biopsies & autopsies) for identifying diseases (particularly cancers).
• Forensic Pathologists: Conduct autopsies to determine cause of death in cases with suspected foul play or unusual circumstances.
• Research Pathologists: Investigate the molecular and cellular mechanisms of disease to develop new treatments and diagnostic techniques.

Pathology's Contribution to Medical Practice

• Diagnosis: Identify disease through tissue and fluid examination (e.g., infections, cancers, genetic conditions).
• Prognosis: Understand disease severity & progression (e.g., determining cancer stage or infection severity)
• Therapeutic Decisions: Guides treatment choices—particularly in oncology (e.g., selecting chemotherapy regimens).
• Prevention & Early Detection: Develops screening programs for early disease detection (cancer).

Cellular Adaptations & Subcellular Alterations

• Cellular Adaptations: Reversible changes in cell structure or function in response to environmental stress. Help cells survive under difficult conditions.

• Subcellular Alterations: Changes at the organelle or molecular level. Can be reversible or irreversible, impacting cellular function.

• Types of Cellular Adaptations: Hypertrophy (increased cell size), Atrophy (decreased cell size), Hyperplasia (increased cell number), Metaplasia (change in cell type), Dysplasia (abnormal cell development).

• Subcellular Alterations (example): Mitochondrial Alterations, Endoplasmic Reticulum Stress, Lysosomal Changes (damaged organelles lead to specific issues in certain diseases).

Next Week

• Quiz.