What is Type III hypersensitivity? Type III hypersensitivity, also known as immune complex hypersensitivity, is an immune response that involves the formation of immune complexes (antigen-antibody complexes) usually in the circulation. These immune complexes can deposit in blood vessels, leading to activation of complement, inflammation, and tissue injury. In Type III hypersensitivity, the antigens are […] The post Type III hypersensitivity appeared first on Pathology Made Simple ..read more

What is Type II Hypersensitivity? Type II hypersensitivity, also known as antibody-mediated hypersensitivity, involves the immune system’s response where antibodies interact antigens attached to cell surfaces or within the extracellular matrix, leading to tissue injury, inflammation, or cellular dysfunction. Type II differs from other hypersensitivity reactions  in its specificity for cell-bound antigens, leading to direct […] The post Type II Hypersensitivity appeared first on Pathology Made Simple ..read more

What is metaplasia? Metaplasia is a reversible cellular adaptation in which one differentiated cell type (epithelial or mesenchymal) is replaced by another cell type. This change occurs in response to chronic inflammation or irritation and represents a survival mechanism to withstand adverse conditions. What causes metaplasia? Metaplasia arises from reprogramming of stem cells present in […] The post Metaplasia: Types and Causes appeared first on Pathology Made Simple ..read more

What is hyperplasia? Hyperplasia is an increase in the number of cells in an organ or tissue, which can lead to the organ’s enlargement. This process only occurs if the cell population is capable of dividing. Can all cells undergo hyperplasia? No, NOT all cells can undergo hyperplasia. Cells that are incapable of dividing, such […] The post Hyperplasia- Mechanism and Causes appeared first on Pathology Made Simple ..read more

What is hypertrophy? Hypertrophy is the increase in the size of the parenchymal cells in an organ. What causes hypertrophy? Hypertrophy can be caused by increased functional demand or stimulation by hormones and growth factors. Essentially, when an organ is under stress or is stimulated to grow, the cells may respond by getting larger. What […] The post Hypertrophy: Mechanism & Causes appeared first on Pathology Made Simple ..read more

What changes happen to the brain in Alzheimer’s disease? In Alzheimer’s, the brain shows cortical atrophy, particularly in the frontal and temporal lobes, meaning it shrinks in size. This results in wider gaps between brain folds and smaller brain ridges. The brain’s ventricles, or fluid-filled spaces, also enlarge as the brain volume decreases. Which parts […] The post Alzheimer’s disease – Pathology and clinical features appeared first on Pathology Made Simple ..read more

What is Alzheimer’s disease? Alzheimer’s disease is the most common cause of dementia among older adults, marked by the degeneration of neuronal cells, leading to impairments in cognitive functions, motor skills, behavior, and ultimately resulting in death. Who discovered Alzheimer’s disease and when? Dr. Alois Alzheimer, a German psychiatrist and neuropathologist, first identified Alzheimer’s disease […] The post ALZHEIMER’S DISEASE – Pathogenesis appeared first on Pathology Made Simple ..read more

Type I Hypersensitivity reaction. What are hypersensitivity reactions? Hypersensitivity reactions are injurious immune reactions characterized by excessive or harmful reactions of the immune system to antigens. The antigens can be exogenous from the environment or endogenous self-antigens. They usually result from an imbalance between effector and regulatory mechanisms, with most often failure in normal regulation […] The post Type I Hypersensitivity reaction. appeared first on Pathology Made Simple ..read more

What is adaptive immunity? Adaptive immunity is part of the immune system that consists of lymphocytes and their products, including antibodies. It is classified into humoral immunity, which combats extracellular microbes and toxins, and cell-mediated immunity, which defends against intracellular microbes and cancers. How is humoral immunity mediated? Humoral immunity is mediated by B lymphocytes, […] The post ADAPTIVE IMMUNITY appeared first on Pathology Made Simple ..read more

What is granulation tissue? Granulation tissue is a type of tissue formed on the surfaces of a wound during the healing process. It is considered the hallmark of the healing process. The term “granulation tissue” comes from the Latin words “granum” (meaning small grain) and “atio” (meaning an action or process), reflecting the grain-like, rough […] The post Granulation tissue appeared first on Pathology Made Simple ..read more