patho

Apoptosis

  • Definition: A regulated process of programmed cell death crucial for maintaining cellular homeostasis.

  • Importance:

  • Removes damaged or unnecessary cells preventing neoplasia (uncontrolled cell growth).

Eschar

  • Definition: Thick, dead tissue that appears black or brown.

  • Implications:

  • Prevents proper healing and requires removal (debridement).

Debridement

  • Definition: The removal of dead, damaged, or infected tissue to enhance the healing process.

  • Methods:

  • Surgical

  • Mechanical

  • Chemical

  • Autolytic

Acute Inflammation

  • Description: The body’s immediate response to injury or infection aimed at eliminating the cause and facilitating healing.

  • Phases:

  1. Vasodilation: Blood vessels widen, increasing blood flow to the area.

  2. Increased Vascular Permeability: Allows immune cells & proteins to enter affected tissue.

  3. Cellular Exudation: Immune cells like neutrophils move to the site to combat injury/infection.

Wound Dehiscence

  • Definition: Partial or complete separation of previously approximate wound edges due to inadequate healing.

  • Risk Factors:

  • Infection

  • Increased tension at the wound site

  • Poor nutrition

  • Underlying medical conditions

  • Consequences: Requires immediate medical attention due to risk of serious complications like infection.

Wound Healing by Secondary Intention

  • Occurs in wounds with larger tissue gap, unable to be closed with sutures or staples.

  • Characteristics:

  • Longer healing time

  • Increased infection risk

  • More significant scarring.

Stages of Wound Healing

  1. Hemostasis: Immediate response to injury to prevent bleeding; clot formation ensues.

  2. Inflammation: Cleansing phase, characterized by redness, warmth, swelling, and pain.

  3. Proliferation: Regeneration of tissue, formation of granulation tissue, angiogenesis.

  4. Wound Contraction and Remodeling: Collagen remodeling occurs, and scar tissue develops.

Sign vs. Symptom

  • Sign: Objective findings observed by healthcare provider (e.g. rash, fever).

  • Symptom: Subjective feelings reported by the patient (e.g. pain, fatigue).

Common Pathogens and Conditions

  • Clostridium tetani: Causes tetanus (muscle stiffness, "lockjaw"). Produces a neurotoxin affecting the nervous system.

  • Clostridium botulinum: Produces botulinum toxin (flaccid paralysis). Small doses used medically (Botox).

  • MRSA: Methicillin-resistant Staphylococcus aureus, can cause severe infections, acquired in community or hospital settings.

  • VRSA: Vancomycin-resistant Staphylococcus aureus, a last-resort antibiotic resistant strain.

Infectious Mononucleosis

  • Commonly known as "mono"; caused by Epstein-Barr Virus (EBV) which remains dormant post-infection.

Types of Hypersensitivity

  • Type I: Immediate hypersensitivity (IgE), e.g., allergies.

  • Type II: Cytotoxic (IgG/IgM), e.g., blood transfusion reactions.

  • Type III: Immune complex-mediated, e.g., rheumatoid arthritis.

  • Type IV: Delayed type (T-cell mediated), e.g., contact dermatitis.

Mast Cells

  • Present in connective tissues and crucial in immediate hypersensitivity reactions, releasing histamine.

Fistula (AV Fistula)

  • Created surgically, connecting an artery to a vein for long-term blood access in hemodialysis.

  • Preferred due to lower infection rates and better blood flow compared to other access sites.

Anemia

  • Definition: Decrease in total red blood cells (RBCs) or hemoglobin, reducing oxygen delivery to tissues.

  • Common Causes:

  • Iron Deficiency (most prevalent)

  • Chronic Disease

  • Folate/B12 Deficiency

  • Sickle Cell Anemia: Genetic disorder with sickle-shaped RBCs, inherited in an autosomal recessive pattern.

  • Iron Deficiency Anemia Treatment:

  1. Oral Ferrous Sulfate

  2. IV Iron Supplementation

  3. Vitamin C for enhanced absorption.

Hemorrhage

  • Losing 30% blood volume can result in shock:

  • Hypotension

  • Tachycardia

  • Reduced urine output.

  • Virchow's Triad: Factors contributing to thrombosis: Venous stasis, hypercoagulability, endothelial injury.

  • Deep Vein Thrombosis (DVT): Blood clot in deep veins, often in the legs; risk factors include age, immobility, obesity.

Varicosity

  • Refers to varicose veins caused by impaired valve function leading to blood pooling.

Huntington’s Disease

  • Genetic disorder affecting brain with progressive nerve cell degeneration:

  • Early: Chorea and impaired coordination

  • Intermediate: Cognitive decline, psychiatric issues

  • Late: Severe motor dysfunction.

Hemophilia

  • Genetic disorder; Deficiency in clotting factors; management involves clotting factor administration and injury avoidance.

Erythroblastosis Fetalis

  • Hemolytic Disease of Newborn; phototherapy used for jaundiced newborns; maternal antibodies against fetal RBCs.

Immune Thrombocytopenic Purpura (ITP)

  • Autoimmune disorder causing decreased platelets post-viral infections; may resolve spontaneously.

Systemic Lupus Erythematosus (SLE)

  • Autoimmune disease attacking self-tissues, characterized by fever, joint pain, and butterfly rash.

Pneumothorax

  • Accumulation of air in pleural space; auscultation may reveal absence of breath sounds or wheezes.

Pleural Effusion

  • Excess fluid in pleural cavity; caused by increased hydrostatic or decreased oncotic pressure.

Pneumonia

  • Inflammatory condition of lung primarily affecting alveoli; causes include bacterial (e.g. Streptococcus pneumoniae), viral, fungal. Symptoms: cough, fever, chills.

Asthma

  • Chronic respiratory condition causing reversible airway narrowing; symptoms include wheezing and breathlessness.

Myocardial Infarction (MI)

  • Sudden blockage of coronary artery leading to heart muscle ischemia and necrosis; common symptoms include crushing chest pain, diaphoresis; confirmed with cardiac troponin.

Heart Failure

  • Chronic condition with impaired heart pumping efficiency; symptoms vary with left/right ventricular failure:

  • Left: Pulmonary congestion, crackles.

  • Right: Jugular venous distension, peripheral edema.

Cor Pulmonale

  • Right-sided heart failure from long-term high pulmonary artery pressure, often due to COPD.

Infective Endocarditis

  • Infection of heart inner lining, commonly in individuals with IV drug use/issues.

  • Exercise Stress Test: Assesses heart's response under exertion, identifies reduced blood flow areas.