How Diseases Disrupt Organ Function: 8 Mechanisms

Disease alters organ structure/function via multiple pathways:

1. Inflammation: Immune response → swelling, pain, dysfunction (e.g., myocarditis, nephritis).
2. Infection: Direct microbial invasion + immune-mediated damage (e.g., TB, viral hepatitis).
3. Structural damage: Trauma, neoplasia, infarction, fibrosis → architectural distortion.
4. Metabolic derangement: Enzyme defects, substrate accumulation, energy failure (e.g., diabetes, mitochondrial disorders).
5. Functional impairment without overt structural change: Ion channelopathies, receptor defects, neurotransmitter dysregulation (e.g., long QT, myasthenia gravis).
6. Vascular compromise: Ischemia (atherosclerosis, thrombosis, vasculitis) → hypoxia, infarction.
7. Immune dysregulation: Autoimmunity (self-attack), immunodeficiency (failed defense), hypersensitivity.
8. Genetic mutations: Developmental defects, protein misfolding, channelopathies (e.g., CFTR, dystrophin).

Clinical Relevance

Understanding mechanism guides targeted therapy: anti-inflammatories, antimicrobials, revascularization, enzyme replacement, gene therapy, immunomodulation.