Patho Week 2 Pathogens PDF

Module 2 – Week 2 Module 2 Topics // Pathogens; Immune System and WBC Disorders; UTI Part 1: Pathogens A. Pathogens: Organisms that cause disease to their host Most common causes of infection: 1. Bacteria (streptococcus pyogenes, streptococcus pneumoniae, E. coli) o Bacteria shapes...

Module 2 – Week 2 Module 2 Topics // Pathogens; Immune System and WBC Disorders; UTI Part 1: Pathogens A. Pathogens: Organisms that cause disease to their host Most common causes of infection: 1. Bacteria (streptococcus pyogenes, streptococcus pneumoniae, E. coli) o Bacteria shapes: ▪ Cocci ▪ Bacilli ▪ Spirilla 2. Viruses (coronavirus, rhinovirus, influenza, herpes simplex o Steps of viral infection: 1. Attachment a. Notes: 2. Penetration a. Notes: 3. Uncoating a. Notes: 4. Replication a. Notes: 5. Assembly a. Notes: 6. Release 15 Version: August 2024  a. Notes: 3. Protozoa (giardia, malaria, scabies, lice) o Key features: single-celled organisms that cause harm o Additional examples: Malaria, Giardia, Trichomoniasis, Toxoplasmosis 4. Fungi (tinea, candida) a. AKA mycotic infection` 5. Helminths/Worms (pin worm, tape worm) 16 Version: August 2024 B. Routes of Transmission and Establishing Infection Routes of Transmission Aerosol, Airborne, Droplet Contact Fomite Contact Direct Contact Vector Transmission Oral Transmission Zoonotic Transmission Establishing Infection (5) 1. Entrance a. Notes: 2. Adherence a. Notes: 3. Colonization a. Notes: 4. Avoid Host Defenses a. Notes: 5. Create Host Injury a. Notes: Additional Terms to Know Colonization: An increase in the amount of a microorganism present at a given location (replication / growth) o The presence of microorganisms (flora) without infection or harm Virulence: A pathogen’s ability to cause disease (influenced by toxins, adherents, evasion) Nosocomial Infection: A hospital-acquired infection that occurred in the hospital/clinical setting 17 Version: August 2024  Opportunistic Infection: An infection that occurs when microbes that typically do not cause disease take advantage of certain conditions and become pathogenic C. Stages of Infection Stages of Infection (6) 1. Exposure a. Notes: 2. Incubation a. Notes: 3. Prodrome a. Notes: 4. Acute a. Notes: 5. Convalescent a. Notes: 6. Resolution a. Notes: D. Testing for Microbes (with a focus on bacteria) Goal: Identify what type of bacteria we are looking at Q. Where can samples come from? Gram Stain: A way to organize bacteria into one of two groups to understand which type of antibiotic would be best Culture: A test that tells the identity of bacteria Sensitivity: A test that tells us which specific antibiotics are best to treat the bacterial infection 18 Version: August 2024  Gram Stain: A dye is used that gets trapped in the thick peptidoglycan layer of gram positive bacteria, causing them to look purple. The dye is not trapped in the single peptidoglycan layer in gram negative bacteria and washes out (appearing red). o Gram Positive Notes: o Gram Negative Notes: Culture and Sensitivity: Culture: A patient sample that is grown within a laboratory setting to help identify which bacteria is present Sensitivity: Bacterial culture is subjected to variety of antibiotics to determine which are most effective against the pathogen present Incidence and Prevalence: Incidence: new cases (Incidents) Prevalence: all cases (PrevALLence) E. Tuberculosis (bacteria) Symptoms: 19 Version: August 2024 Part 2: Immune System and WBC Disorders A. Primary Lymphoid Organs 4 Primary Lymphoid Organs: 1. Bone Marrow: A primary lymphoid organ o Site of hematopoiesis o Produces all immune cells o Site of B-cell maturation o Unidirectional exit for cells to enter blood / lymphatics 2. Thymus: A primary lymphoid organ o Site of T-Cell Maturation o Shrinks from puberty onward, but still active 3. Lymph Nodes/Lymphatics o Immune surveillance o Present anywhere that the body bends or regions come together o Filters fluid from the tissue o Removes foreign matter from the tissue o Removes waste from the tissues o Proliferates immune cells (B- and T-cells 4. Spleen o Acts as a massive lymph node o Home to white pulp o Mononuclear phagocyte system o Removes and destroys antibody-coated bacteria / RBC’s o Filters blood o Removes dead / damaged RBC’s o Filters antigens from the blood o B- and T-cells exist in the spleen B. Innate and Adaptive Immune System Immune system definition: a defense against pathogens and the environment around us o Innate (humoral) vs. Adaptive (compliment) 20 Version: August 2024  Red Blood Cells: White Blood Cells: o Neutrophils (polymorphic leukocytes) ▪ Notes: o Eosinophils (acidophils) ▪ Notes: o Basophils ▪ Notes: o Monocytes ▪ Notes: o Lymphocytes 21 Version: August 2024  ▪ Notes: Innate vs. Adaptive o Innate = NONSPECIFIC o Adaptive = SPECIFIC ▪ Fast response (0-4 hours) ▪ Slow response (4-14 days) C. Humoral Immunity and Hypersensitivity Reactions Humoral Immune System: The 5 Immunoglobulins o IgG: o IgA: o IgM: o IgE: o IgD: 22 Version: August 2024  Hypersensitivity Reactions (4 Types) 1. Type I: IgE & Mast Cells a. Allergic responses b. Examples: 2. Type II: IgM / IgG a. Cytotoxic responses b. Examples: c. (Compliment) 3. Type III: Antigen-Antibody Complex a. Immune complex b. Examples: c. (Compliment, IgG, IgM, Neutrophils) 4. Type IV: Cell-Mediated Reactions a. Delayed Type Hypersensitivity Reaction (DTH): 24-48 hours after exposure / contact b. Examples: c. (Cytotoxic T Cells, Natural Killer Cells, Macrophages) Allergic Response: o Risk of anaphylaxis: extreme allergic response characterized by involvement of 2 or more bodily systems ▪ Urticaria and respiratory involvement ▪ Treat with epinephrine 23 Version: August 2024  Transplant Rejection: o Background: Almost every cell in the body has a “name tag” called a human leukocyte antigen (HLA) ▪ Role of HLA: Lets the immune system know that the cell belongs o During organ transplants it is important to receive donor tissue that matches the recipient’s ________________ as closely as possible to prevent the immune system from ________________ the tissue o Types of Transplants (2) 1. Autologous 2. Allogenic o Types of Rejection (3) 1. Hyper-acute 2. Acute 3. Chronic D. Active and Passive Immunity Goal: IMMUNITY Vaccine Types (5) 1. Inactivated: 2. Attenuated: 3. Toxoid: 4. Subunit: 5. Conjugate: E. Autoimmune Disease Background: The immune system is a complex system of chemicals, cells, signals and other parts. 24 Version: August 2024 When one or more of these parts “accidentally” targets the body instead of foreign particles, we can develop _____________________ disease. The signs / symptoms of each autoimmune disease are specific to the parts of the immune system involved and their specific targets. F. Immunodeficiency and HIV Immunodeficiency: A condition that develops as the result of a compromised immune system o May be temporary or permanent o Increases the likelihood of “opportunistic infections” o Common causes of immunodeficiency: HIV Infection: HIV: A Quick Reference o Definition: a virus that selectively targets CD4 lymphocytes (T-Helper Cells) ▪ Results in a failure of the adaptive immune system ▪ Increases risk of uncommon infections and cancers o Caused by exposure to infected bodily fluids ▪ Causes: 25 Version: August 2024  o Signs and symptoms: o Stages of HIV Infection (3) ▪ Acute: ▪ Latent: ▪ AIDS: o HIV and Viral Load: ▪ Viral load is the concentration of a virus within a person (ability to infect others) ▪ Antiretroviral therapy is important to: Lower viral load Prevent mutation of the disease Decrease spread G. WBC Disorders Hodgkin’s vs. Non-Hodgkin’s Lymphoma Leukemia: Cancer of the bone marrow cells 26 Version: August 2024  o Myeloid cells: basophils, eosinophils, neutrophils o Lymphoid cells: T cells, B cells Part 3: Urinary Tract Infection (UTI) A. Urinary Tract Infection: E. Coli accounts for 75-95% of UTIs 27 Version: August 2024