Pharmacology & Physiology Review

• Exotoxins: Toxins secreted by bacteria that can damage a host by destroying cells or disrupting normal cellular metabolism.
• Endotoxins: Toxins secreted by bacteria that can damage a host by destroying cells or disrupting normal cellular metabolism.

Infectivity, Communicability, and Virulence

• Infectivity: The ability of a pathogen to invade and multiply in a host.
• Communicability: The ability of a pathogen to spread from one individual to another.
• Virulence: The degree of ability of a microorganism to cause severe disease or harm to a host.

Narrow Spectrum Antibiotics

• Narrow Spectrum Penicillin and Cephalosporin: Effective against gram-positive bacteria.
• Narrow Spectrum Aminoglycoside: Effective against gram-negative bacteria.

Cephalosporin Generations

• First Generation Cephalosporins: Effective against gram-positive bacteria and have more bacterial resistance.
• Higher Generation Cephalosporins: Effective against gram-positive and gram-negative bacteria, but have less bacterial resistance.

Antibiotics for MRSA

• Vancomycin: Inhibits cell wall synthesis and is used for severe infections, including MRSA.
• Fifth Generation Cephalosporin (Ceftaroline): used for infections associated with MRSA.

Antibiotics for Pseudomonas

• Fourth Generation Cephalosporin (Cefepime): Used to treat health-care and hospital-associated pneumonias caused by Pseudomonas.

Antibiotics that Inhibit Cell Wall Synthesis

• Penicillin: Weakens the cell wall, causing bacteria to take up excessive water and rupture.
• Cephalosporin: Similar mechanism of action, inhibits cell wall synthesis.
• Vancomycin: Inhibits cell wall synthesis and is effective against Gram-positive bacteria.

Mechanisms of Protein Inhibitors

• Macrolides: Inhibit protein synthesis.
• Aminoglycosides: Inhibits protein synthesis, bactericidal, and used for aerobic Gram-negative bacilli.
• Tetracyclines: Inhibit protein synthesis and are broad-spectrum antibiotics.

DNA and Folic Acid Inhibitors

• Sulfa and Trimethoprim (Sulfonamides and Trimethoprim): Suppress bacterial growth by inhibiting tetrahydrofolic acid, a derivative of folic acid or folate.

Allergic Reactions to Antibiotics

• Penicillin and Cephalosporins: Penicillin allergies are more common; anaphylaxis is the most severe reaction, characterized by bronchospasm, laryngeal edema, and hypotension.
• Sulfa Antibiotics: Common mild reactions include rash, drug fever, and photosensitivity.

Aminoglycoside Side Effects

• Ototoxicity
• Nephrotoxicity

P-450 Inhibitor

• Grape fruit juices

Opioid Side Effects

• Constipation
• Decreased respiratory rate
• Sedation
• Euphoria
• Hypotension

Cyclosporine Side Effects

• Nephrotoxicity
• Hepatotoxicity
• Increase chance of infection

NSAID Side Effects

• Nausea
• Vomiting
• Abdominal pain
• GI bleeding
• Nephrotoxicity

Glucocorticoid Side Effects

• Hypertension
• Increased chance of infection
• Hyperglycemia
• Breakdown of skin, muscle, and bones
• GI side effects (nausea, vomiting, abdominal pain)
• GI bleeding

Hypersensitivity Type IV

• Only T lymphocytes involved
• No antibody present
• Delayed response

Autoimmune Disorders

• Lupus
• RA (Rheumatoid Arthritis)
• Graves
• Type 1 DM (Diabetes Mellitus)

Hypersensitivity Type I

• Involves mast cells, IgE, genetic link
• Causes a prompt reaction (20 minutes)
• Symptoms include mild hives and rash to life-threatening anaphylaxis

Hypersensitivity Type II and III

• IgG and IgM cause autoimmune disorders
• Can cause transfusion reactions and Rh disease of fetus

C Pain Fibers

• Unmyelinated

Delta Pain Fibers

• Located in the skin
• Fast transmission
• Highly localized

Referred Pain

• Pain perceived at a location other than the site of the painful stimulus

Cause for Referred Pain:

• It often occurs due to the sharing of sensory pathways between the site of injury and the referred area.

Benefits of Low-Grade Fever

• Kills invading microorganisms
• Promotes lysosomal breakdown and autodestruction of infected cells
• Increases lymphocytic transformation and phagocytic motility
• Augments antiviral interferon production
• Augments phagocytosis

Danger of Hyperthermia

• Heat cramps, exhaustion, heatstroke
• Nerve damage at temperatures ≥ 41°C (105.8°F) leading to convulsions
• Death at temperatures ≥ 43°C (109.4°F)

Active Immunity

• An individual's immune system responds to a foreign substance (antigen) and produces antibodies, such as through natural exposure to a pathogen or through vaccination
• Example: Getting vaccinated against measles

Passive Immunity

• A person is given antibodies to a disease rather than producing them through their immune system, such as antibodies passed from mother to baby through breast milk, or artificially through antibody-containing blood products
• Example: Receiving antibodies for rabies after exposure to the virus

Superinfection

• Infection that occurs on top of an existing infection, usually due to the disruption of normal microbial flora by antibiotics, allowing opportunistic pathogens to overgrow

COPD (Barrel Chest)

• A physical characteristic often seen in advanced COPD where the chest becomes rounded and enlarged due to chronic overinflation of the lungs

Glucocorticoid Inhalers

• Use daily regardless of having asthma or not

Emphysema

• Main pathogenesis involves the destruction of the alveoli (air sacs) in the lungs, leading to decreased surface area for gas exchange and difficulty in breathing

Chronic Bronchitis

• Increase in mucus production and inflammation in the airways, leading to coughing and difficulty in breathing

Albuterol

• Is a beta 2 agonist that treats asthma by opening the airways (bronchodilator)

Pleural Effusions

• Transudative: Caused by fluid leaking into the pleural space due to increased pressure or low protein content; often seen in heart failure or cirrhosis
• Exudative: Caused by inflammation, infection, or malignancy, leading to fluid with high protein content and cellular debris
• Hemorrhagic: Contains blood, often due to trauma
• Chylous: Contains lymph fluid, often due to injury or obstruction of the thoracic duct

Signs and Symptoms of Acute Asthma

• SOB (Shortness of Breath)
• Wheezing
• Chest tightness
• Coughing

Pathogenesis of Asthma

• Chronic inflammation of the airways leading to hyperresponsiveness
• Bronchoconstriction
• Airflow obstruction
• Allergens, infections, etc

Temperature Benefit of Fever

• Kills invading microorganisms
• Promotes lysosomal breakdown and autodestruction of infected cells
• Increases lymphocytic transformation and phagocytic motility
• Augments antiviral interferon production
• Augments phagocytosis

Hyperthermia Stages and Symptoms

• Heat Cramps: Painful muscle contractions due to loss of fluids and electrolytes
• Heat Exhaustion: Symptoms include heavy sweating, weakness, dizziness, nausea, and headache
• Heatstroke: A medical emergency where body temperature exceeds 41°C (105.8°F), causing confusion, seizures, and potential death

Factors of Infection

• Pathogenicity, microbial adherence, invasion, communicability, virulence, immunogenicity, infectivity, bacteremia or septicemia, and portal of entry

Factors Increasing Infection Risk

• Malnutrition
• Age
• Chronic illness
• Stress
• Immunosuppression
• Recent antibiotic use

Bacterial Infection

• Exotoxins: Toxins secreted by bacteria
• Endotoxins: Components of the outer membrane of Gram-negative bacteria released upon bacterial cell death
• Endospores: A form of bacterial resistance that can withstand extreme conditions and germinate when conditions are favorable, ensuring the survival of the bacterium

Antimicrobial Resistance

• Bacteria become resistant to antibiotics, making infections harder to treat; results from overuse or misuse of antibiotics

Aminoglycosides

• Narrow-spectrum
• Treats gram-negative bacteria
• Protein inhibitor
• Side effects include ototoxicity and nephrotoxicity

Nosocomial Infections

• Infections patients acquire during their stay in a healthcare facility, caused by bacteria, viruses, fungi, or parasites, and are often associated with medical procedures or devices like catheters and ventilators

Superinfection

• An infection that occurs on top of an existing infection, usually due to the disruption of normal microbial flora by antibiotics, allowing opportunistic pathogens to overgrow

Antibiotics

• Bactericidal: Kill bacteria directly (e.g., Penicillin)
• Bacteriostatic: Inhibit the growth and reproduction of bacteria, allowing the immune system to eliminate the infection (e.g., Tetracyclines)

Bacterial Distinction

• Gram-Positive Bacteria: Have a thick peptidoglycan cell wall that retains the crystal violet stain, appearing purple under a microscope (e.g., Staphylococcus aureus)
• Gram-Negative Bacteria: Have a thin peptidoglycan cell wall and an outer membrane that does not retain the crystal violet stain, appearing pink under a microscope (e.g., Escherichia coli)

Treatment

• MRSA: Treated with antibiotics like Vancomycin and Fifth-generation cephalosporins (Ceftaroline)
• Pseudomonas: Treated with Fourth-generation cephalosporins (Cefepime) and other antibiotics like Piperacillin-tazobactam

Antimicrobial Classes and Mechanisms

• Penicillin: Inhibits cell wall synthesis; side effects include allergic reactions and gastrointestinal issues
• Cephalosporins: Inhibit cell wall synthesis; side effects include allergic reactions and gastrointestinal issues
• Vancomycin: Inhibits cell wall synthesis; side effects include nephrotoxicity and ototoxicity
• Macrolides: Inhibit protein synthesis; side effects include gastrointestinal issues and hepatotoxicity
• Aminoglycosides: Inhibit protein synthesis; side effects include ototoxicity and nephrotoxicity
• Tetracyclines: Inhibit protein and DNA/folic acid synthesis; side effects include photosensitivity and gastrointestinal issues
• Sulfa antibiotics: Inhibit DNA/folic acid synthesis; side effects include allergic reactions and kidney issues

Cephalosporins inhibit cell wall synthesis

• First-generation treats gram-positive and has more bacterial resistance
• Higher generations treat gram-positive/negative and have less bacterial resistance

Penicillin and Vancomycin both inhibit cell wall of bacteria

Tetracycline

• Protein inhibitor
• DNA/folic acid inhibitor
• Broad spectrum action

Sulfa

• DNA/folic acid inhibitors

Macrolides

• Protein inhibitors

Autoimmune Disorders

• Occur when the immune system mistakenly attacks the body's own tissues, recognizing them as foreign, leading to inflammation and damage to various organs and tissues

Types of Autoimmune Disorders

• Lupus
• RA (Rheumatoid Arthritis)
• Graves
• Type 1 DM (Diabetes Mellitus)

Hypersensitivity Reactions

• Allergens cause immediate specific antibodies to attack specific antigens
• Non-tissue specific, system unable to remove antigen-antibody immune complexes
• Delayed response; only T lymphocytes involved; no antibody present

Allergic Reaction (Histamine)

• Histamine is released by mast cells during an allergic reaction, causing symptoms like vasodilation, increased vascular permeability, and bronchoconstriction

Allergic Reaction (Antibiotics)

• Penicillin, Cephalosporin and sulfa antibiotics can cause allergic reactions ranging from mild rashes to severe anaphylaxis

Immune System Medications (Glucocorticoid drugs)

• reduce inflammation and suppress the immune system- s/e: hypertension, increased risk of infection, hyperglycemia, break down of skin, muscle and bones

Immune System Medications (Cyclooxygenase)

• reduce inflammation and pain

Inflammation

• Body response to injury or infection, characterized by redness, swelling, heat, pain, and loss of function

Exudate Types

• Serous: Clear, watery fluid
• Fibrinous: Thick, sticky, and contains high levels of fibrin
• Purulent: Contains pus, indicating infection
• Hemorrhagic: Contains blood, indicating bleeding

Opsonization process

• Pathogens are marked for destruction by the immune system
• The complement cascade enhances the ability of antibodies and phagocytic cells to clear microbes and damaged cells

Inflammation

Inflammation

• Localized: occurs at site of injury or infection
• General: Systemic inflammation affecting the entire body

Role of Inflammation

• Macrophages phagocytose pathogens and releases cytokines to mediate Inflammatory response
• Neutrophils phagocytose pathogens, and release free radicals to help kill microbes

Pain and Pain medication

• Pain process involves the transmission of pain signals, at the site of injury to the brain
• Nerve fibers transmits pain signals to the nervous system

The characteristics of types of pain

• Referred: Pain perceives to occur in another area than the pain stimulus
• Tolerance: The maximum amount of pain someone can endure
• Threshold: The miniumum intensity a person can perceive pain.

2 Types of Pain

Delta Pain Fibers

• Fast-paced, highly localized, found in Skin

C- Pain Fibers

• Unmyelinated, Slow, poorly localized

Mechanism of Opioids

• Works by binding to opioid receptors in the brain, to reduce pain

Side Effects to Opioids

• Constipation
• Decreased Heart Rate
• Sedation
• Euphoria
• Hypotension

Narcan

• Effects Reverse Opioids

Buprenorphine

• A partial Opioid Angonists, used for Pain dependance

Test your knowledge of antibiotics mechanisms (cell wall, protein, and DNA synthesis inhibitors) and adverse effects (photosensitivity, nephrotoxicity). Review the pathophysiology of asthma and fever, and identify symptoms of heat exhaustion.