General Pathology: Disease Study

• Pathology is the study of disease, encompassing its causes, mechanisms, progression, and effects
• It bridges basic science and clinical medicine
• It involves examining tissues, cells, and body fluids to diagnose and understand diseases
• Pathology helps inform clinical decision-making

General Pathology

• General pathology focuses on the fundamental mechanisms and common reactions to injury or disease
• It covers a wide range of disease processes that affect multiple organ systems
• Inflammation: A protective response to injury or infection involving immune cells and mediators, leading to tissue repair or damage
• Cell Injury: Occurs when cells are exposed to stress or damaging stimuli exceed their ability to adapt
• Necrosis: Cell death due to irreversible damage, characterized by cell swelling, membrane rupture, and inflammation
• Apoptosis: Programmed cell death, a controlled process with cell shrinkage, DNA fragmentation, and no inflammation
• Hyperplasia: Increase in cell number due to increased cell division in response to a stimulus
• Hypertrophy: Increase in cell size due to increased synthesis of cellular proteins and organelles
• Atrophy: Decrease in cell size and/or number due to reduced demand or stress
• Metaplasia: Reversible change in which one mature cell type is replaced by another cell type
• Neoplasia: Abnormal new growth of cells, which can be benign or malignant (cancer)
• Genetic and environmental factors play significant roles in the pathogenesis of diseases
• Pathological findings provide insights into disease mechanisms and potential therapeutic targets

Systemic Pathology

• Systemic pathology examines diseases affecting specific organ systems
• Cardiovascular Pathology: Diseases of the heart and blood vessels, such as atherosclerosis, hypertension, and heart failure
  • Atherosclerosis: Characterized by plaque formation in arteries, leading to reduced blood flow and potential ischemic events
  • Hypertension: High blood pressure, a major risk factor for heart disease, stroke, and kidney disease
  • Heart Failure: The heart's inability to pump enough blood to meet the body's needs, often due to underlying heart conditions
• Respiratory Pathology: Diseases of the lungs and airways, such as pneumonia, asthma, and chronic obstructive pulmonary disease (COPD)
  • Pneumonia: Lung infection caused by bacteria, viruses, or fungi, leading to inflammation and fluid accumulation
  • Asthma: Chronic inflammatory disorder of the airways, causing reversible airflow obstruction and wheezing
  • COPD: Progressive lung disease characterized by airflow limitation, often due to smoking or environmental pollutants
• Gastrointestinal Pathology: Diseases of the esophagus, stomach, intestines, liver, and pancreas, such as gastritis, inflammatory bowel disease (IBD), and cirrhosis
  • Gastritis: Inflammation of the stomach lining, often caused by Helicobacter pylori infection or NSAID use
  • Inflammatory Bowel Disease (IBD): Chronic inflammation of the gastrointestinal tract, including Crohn's disease and ulcerative colitis
  • Cirrhosis: Scarring of the liver due to chronic liver damage, leading to impaired liver function
• Renal Pathology: Diseases of the kidneys, such as glomerulonephritis, nephrotic syndrome, and renal failure
  • Glomerulonephritis: Inflammation of the glomeruli in the kidneys, leading to impaired filtration and proteinuria
  • Nephrotic Syndrome: Kidney disorder characterized by proteinuria, edema, hyperlipidemia, and hypoalbuminemia
  • Renal Failure: Loss of kidney function, which can be acute or chronic, requiring dialysis or transplantation
• Endocrine Pathology: Diseases of the endocrine glands, such as diabetes mellitus, thyroid disorders, and adrenal disorders
  • Diabetes Mellitus: Metabolic disorder characterized by hyperglycemia due to insulin deficiency or resistance
  • Thyroid Disorders: Conditions affecting thyroid hormone production, such as hypothyroidism (underactivity) and hyperthyroidism (overactivity)
  • Adrenal Disorders: Conditions affecting adrenal hormone production, such as Cushing's syndrome (excess cortisol) and Addison's disease (cortisol deficiency)
• Hematopathology: Diseases of the blood, bone marrow, and lymphoid tissues, such as leukemia, lymphoma, and anemia
  • Leukemia: Cancer of the blood-forming tissues, leading to abnormal white blood cell production
  • Lymphoma: Cancer of the lymphatic system, involving lymphocytes
  • Anemia: Deficiency of red blood cells or hemoglobin, resulting in reduced oxygen-carrying capacity
• Neuropathology: Diseases of the nervous system, such as Alzheimer's disease, Parkinson's disease, and stroke
  • Alzheimer's Disease: Progressive neurodegenerative disorder characterized by cognitive decline and memory loss
  • Parkinson's Disease: Neurodegenerative disorder affecting motor function, characterized by tremor, rigidity, and bradykinesia
  • Stroke: Disruption of blood flow to the brain, leading to tissue damage and neurological deficits
• Musculoskeletal Pathology: Diseases of the bones, joints, and muscles, such as osteoarthritis, rheumatoid arthritis, and muscular dystrophy
  • Osteoarthritis: Degenerative joint disease characterized by cartilage breakdown and joint pain
  • Rheumatoid Arthritis: Autoimmune disorder causing chronic inflammation of the joints
  • Muscular Dystrophy: Genetic disorders characterized by progressive muscle weakness and degeneration
• Dermatopathology: Diseases of the skin, such as eczema, psoriasis, and skin cancer
  • Eczema: Inflammatory skin condition characterized by itching, redness, and rash
  • Psoriasis: Chronic skin condition characterized by raised, scaly plaques
  • Skin Cancer: Abnormal growth of skin cells, including basal cell carcinoma, squamous cell carcinoma, and melanoma
• Each organ system has unique pathological features and clinical manifestations

Diagnostic Pathology

• Diagnostic pathology involves the examination of tissues, cells, and body fluids to diagnose diseases
• Histopathology: Microscopic examination of tissue samples to identify abnormalities and diagnose diseases
• Cytopathology: Microscopic examination of individual cells or small clusters of cells to diagnose diseases
• Molecular Pathology: Analysis of DNA, RNA, and proteins to identify genetic mutations, infectious agents, and other molecular markers of disease
• Immunopathology: Use of antibodies to detect specific antigens in tissues or cells, aiding in the diagnosis of autoimmune diseases, infections, and cancers
• Forensic Pathology: Application of pathological principles to legal matters, such as determining the cause of death
• Autopsy: Postmortem examination to determine the cause of death and study the extent of disease
• Biopsy: Removal of tissue sample for diagnostic examination
• Pathologists play a crucial role in patient care by providing accurate and timely diagnoses, informing treatment decisions, and monitoring disease progression