patho test 3
viruses
a virus is a very small obligate intracellular parasite that requires a living host cell for replication Related to cancers Provide more genetic variations -Requires a living host for survival Obligate parasite→ cannot conduct their functions on their own (relying on another cell) Uses living cell for replication Outside of a living cell it's called a virion -Structure Capsid Protein coat -Core DNA or RNA (retrovirus) + enzyme to become DNA (HIV is a retrovirus) -Some have an outer "envelope." Table 6.2 helps Tissue injury→ inflammation Influenza virus - Strong propensity to mutate *one type of virus exists in many similar forms or strains and they tend to mutate or change a little during replication (EX: cold or flu) * these factors make it hard for a host to develop immunity to a virus - Contain RNA (retrovirus) or DNA -virions consist of protein coat or capsid and a core (either dna or rna) -retrovirus like HIV contains rna only, plus an enzyme to convert rna into dina -additional outer protective envelope -new viruses are assembled and then released by lysis of the host cell or by budding from the host cell membrane -- usually with destruction of the host cell -may alter host cell chromosomes leading to cancer or malignant cells
Pathogenicity
ability of a microorganism to cause disease -Pathogenicity → a microorganism's capacity to cause disease (do these things CAUSE disease? Describes organsims's capacity to cause disease Pathogenicity of ______ is low and does not tend to cause us a disease MRSA can cause disease capacity of microbes to cause disease (nonpathogens can become pathogens) EX: escherichia coli from the colon enter the urinary tract (will cause infection)
Natural passive immunity
acquired by a child through placenta and breast milk Passive (antibodies supplied from another source) → antibodies from other sources Natural Maternal antibodies passed to child during gestation and through breast feeding. Passed to child, also through breast feeding passive immunity occurs when antibodies are transferred from one person to another when IgG is transferred from mother to fetus across the placenta antibodies protect the infant for first few months of their life antibodies are directly passed from mother to child to provide temporary protection there is no memory
• subclinical infection
an infectious disease not detectable by the usual clinical signs -has organism but little or no signs/symptoms -do not cause apparent signs or symptoms, although they may persist over long periods of time
epidemic
a widespread occurrence of an infectious disease in a community at a particular time. a disease occurring in higher numbers than usual in a certain population within a given period
primary infection
acute infection that causes the initial illness -First caused by initial microorganism Examples??? Got a virus, got an infection from it -initial or first time exposure/infection
pyrexia
fever
Extremity X-ray
gangrene use
prions
infectious protein particles that do not have a genome -replicating infectious proteins that damage tissues (usually the brain) -protein-like agents that are transmitted by consumption of contaminated tissues such as muscle or the use of donor tissues contaminated with the protein **replicating infectous proteins that damage tissues (usually the brain)** -creutzfeldt-jakob disease (caused by consumption of meat that has been contaminated with nervous tissue from an infected animal like beef cattle)
onset
the beginning or start Onset: In medicine, the first appearance of the signs or symptoms of an illness as, for example, the onset of rheumatoid arthritis the onset of a specific infection may be insidious, with a prolonged or gradual prodromal period, or sudden or acute, with the clinical signs appearing quickly w/ severe manifestation
Toxemia
toxins in the blood -presence of toxins in the blood
carrier
Sublclinical → has organism but little or no signs/symptoms Clinical → manifestation of diseases in signs/symptoms Picks up microorganism but does not get disease itself but can still pass it on to someone else (does not show disease but can carry it and spread it to someone) -never develop the infection (EX: hep B) a person hosting an infectious pathogen who shows no signs of the disease but could transmit the infection to others
lymphadenopathy
disease of the lymph nodes - occurs and is manifest by swollen and tender lymph nodes
Nuclear Medicine three-phase bone scan
for osteomyelitis
Radiologic exam
may be used to identify the site of the infection and may assist in the identification of the agent ex: lung congestion localized in one lobe (consolidation) usually indicates penumococcal penumonia
Active natural immunity
natural exposure to an antigen active immunity develops when the person's own body develops antibodies or t cells in response to a specific antigen introduced in the body Active (antibodies produced by "host" organism) → make your own antibodies Natural → get the disease through active means The process of developing antibody memory (as we examined). When you get the flu (someone blew droplets on you)--> natural active immunity direct exposure to an antigen (EX: person has an infection and then develops antibodies) pathogens enter the body and cause an illness, antibodies form in the host, there is memory person w/ chicken pox once
reservoir
population that holds/is a big source of the microorganisms Ex: reservoir for rabies are raccoons (bat = vector) a site where pathogens can survive or multiply source of infection -- may be a person with an obvious active infection in an acute stage or person who does not show signs -EX: animals or contaminated water, soil, food, or equipment
Viremia
viruses in the blood -presence of virus in the blood
Describe the disorder systemic lupus erythematosus (SLE), its pathophysiology, clinical manifestations, diagnostic tests, and treatment
'butterfly' rash Affects connective tissue Breakdown of collagen and vessel linings Females, 20-40 yo Joint pain Fever Chronic inflammation of organs autoimmune disorder Organs become infiltrated with chronic inflammation cells Organ failure can result Kidneys and heart often affected Psychosis and behavioral disorders are commonly seen Has periods of remission and exacerbation extent of disease can vary, but lupus can be fatal SLE Diagnosis: * Characterized by presence of antinuclear antibodies (ANA). The victim has antibodies to her own DNA Diagnosis is based on a minimum of four affected systems. Presence of numerous ANAs, especially anti-DNA is positive for SLE. Presence of LE cells (form of neutrophil) "Sed" rate is high (erythrocyte sedimentation rate)—a result of inflammatory response treatment: Prednisone Reduces immune response live a normal life span stress can cause -- changes life style NSAIDs Anti-inflammatory Hydroxychloroquine (anti-malaria drug) Reduces exacerbation facial rash affects primarily women and becomes manifest between the ages of 10 and 50 years old large numbers of circulating autoantibodies against dna, platelets, erythocrytes, etc common sites: kidneys, lungs, heart, joints, digestive tracts signs and symptoms: -skin rash or joint inflammation diagnostic test: -anas (antinuclear antibodies) signs and symptoms treatment: -rheumotologist -prednisone -NSAIDs -avoiding aggravating factors common manifestations: -joints (painful) -skin (butterfly rash, sun exposure, hair loss) -kidneys (renal damage) -lungs (chest pain) -heart -CNS (depression, mood changes, seizures) -bone marrow (anemia)
Describe the cause, modes of transmission, and implications for health professionals of acquired immunodeficiency syndrome. (AIDS)
**know that blood contains the most virus of an HIV infected person** AIDS Virus destroys body's immune system Death by common infections Virus = human immunodeficiency virus (HIV-1) What is AIDS v. HIV???? Body fluids (blood & semen) Enters via tear in mucosa Examples: shared needles, sexual transmission, perinatal, contaminated blood products Not by casual contact (handshake, door knobs, toilet seats) AIDS is a chronic infectious disease caused by HIV which destroys helper T cells, causing a loss of the immune response and increased susceptibility to secondary infections AIDS is active infection a retrovirus which cotains rna infects the cd4 t helper cells (decrease in function and number of cells) polymerase chain reaction transmission: -virus must find entry into the circulating blood of the recipient -blood contains the highest concentration of virus, semen is next -HIV present in saliva *health care workers should assume there is a risk of some infection from contact with body fluids from any individual and follow universal precautions * all clients must be treated as though they may be infected *transmission is suspected: health care worker should seek counseling and post exposure prophylaxis
HSV 1 (herpes simplex virus 1)
- Fever and general malaise - Painful vesicular lesions (cold sores) usually clustered, lasting 3-7 days - Meningo-encephalitis - Keratitis - Whitlow - Gladitorium - Histologic Cowdry type A intranuclear inclusions and syncytia - Mucosal-epithelial cells - Enveloped dsDNA - Latent in trigeminal ganglia (HSV-1, or oral herpes) Herpes simplex type 1, which is transmitted through oral secretions or sores on the skin, can be spread through kissing or sharing objects such as toothbrushes or eating utensils
Recognize different techniques to reduce transmission what characterizes them
-Disinfection Reduce organisms to harmless levels (spores survive) → formalin and bleach Use CHEMICALS → reduce levels really low so nothing colonizes to invade tissues -Antisepsis Reduce organisms on tissues → iodine and alcohol Used on the SKIN antimicrobial chemicals designed to be used on living tissue such as isopropul alcohol reduce the number or organisms in an area by often do not destroy all o them some can cause allergic reactions -Sterilization Kill them all → even spores → autoclaving Temperature really high (pressurized boiling is autoclave) Burning things KILL EVERYTHING -complete destruction and removal of all microorganisms by exposure to heat (autoclaving) -moist heat penetrates more efficiently and destroys microbes at lower temps -Aseptic technique Minimize contact bw tissue and germs → used in surgery, wound care, and IVs Minimize any contact with bacteria -Sanitation Housekeeping disinfection (cleaning with bleach, disinfections, sanitation) -adequate cleaning of surroundings and clothing -disinfectants chemical solutions designs to be used on nonliving surfaces adequate exposure time and concentration of chemical are required to kill viruses
Describe the onset and course of an infection
-Incubation period Microbes incubate (then they start to damage tissues and getting inflammation) → can be a few days (takes time for signs to show up) -Prodromal period Think you are coming down with something, but no symptoms or signs are really distinct Can feel really drained (like night and day) You think you are coming down with something -Acute period → recovery? You have all of the signs or symptoms of what is going on Self-limited (just have to go through it; body will eventually develop immunity and fight it off) Yes = signs subside until total recovery No -Septic Affect all tissues and the whole body → can cause you to die Overwhelming infection → Septicemia (death)? Chronic infection Like MRSA -microorganisms must gain entry to the body, choose a hospitable site, establish a colony, and begin reproducing 1. pathogen enters the host 2. pathogen colonizes approp. sites 3. pathogen reproduces rapidly 4. prodromal signs may appear 5. acute signs are present 6. decreased reproduction and death of pathogens (host defenses take effect, nutrient supply decreases, wastes and cell debris inc., antibacterial drug) 7. recovery -- signs subside 8. total recovery chronic infection (mild signs are destructive) septicemia = death
Major components of the immune system/their functions
antigen-- foreign substance, microbes, or comp. of cell that stimulates immune response antibody-- specific protein produced in humoral response to bind w/ antigen autoantibody-- antibodies against self-antigen (attack itself) lymphatic tissue and organs-- contain many lymphs; filter body fluids; remove foreign matter and immune response bone marrow-- source of stem cells, leukocytes, maturations of b lymphs CELLS: neutrophils-- WBC for phagocytosis; nonspecific defense; active in inflamm. process basophils-- WBC, bind IgE, release histamine in anaphylaxis eosinophils-- WBC; participate in allergic response monocytes-- phagocytosis; immune response mast cells-- release chemical mediators in connective tissue (histamine) b lymph plasma cells t lymph cytotoxic or killer t cells-- destroy antigens, cancer cells, virus-infected cells memory t cells helper t cells-- activate B and T cells; control/limit specific immune response NK lymph-- destroy foreign cells CHEMICAL MEDIATORS: complement-- inactive proteins in the circulation (stimulate the release of other chemical mediators and promotes inflamm, chemotaxis, and phago) histamine-- released from mast cells and basophils (in allergic reactions); cause vasodilation and increase perm. or edema kinins (bradykinin)-- cause vasodilation and inc. perm. and pain prostaglandins-- group of lipids with varying effects; cause inflammation, vasodilation, inc. perm, pain cytokines (messengers)-- stimulate activation and proliferation of b and t cells, communication between cells, inflamm, fever, leukocytosis tumor necrosis factor-- stimulates fever and chemotaxis, mediator of tissue wasting, stimulates t cells, mediator in septic shock, necrosis in tumors chemotactic factors-- attract phagocytes to area of inflamm
Basic characteristics of bacteria
-Single-celled, do not need living tissue to survive Do not need living tissue to survive Bacilli-rod-shaped Clostridium tetani (tetanus or "lockjaw") Aka tetany (BACTERIA IS PROKARYOTIC) -Spirals (spirochetes) Treponema pallidum (syphilis) Borrelia burgdorferi (Lyme disease) → carried by the tick (bacteria gets into joints) -Cocci-spherical Diplococci: spherical pairs (travel in pairs) Streptococci: spherical chains (lots of strep bacteria) Streptococcus pyogenes (usually caused strep throat) -Staphylococci: spherical clusters Staphylococcus aureus (MRSA)--> resistant form (found in the skin and outer part of respiratory tract) -Tetrads (grouped in fours) Palisade (grouped lengthwise side-by-side) Rigid cell wall -Gram positive (hold dye)--> does not wash off Tells us something about the cell wall Retain Gram's stain→ thicker peptidoglycan layer Usually cocci bacteria Staphylococcus aureus (strep) Streptococcus pyogenes Streptococcus pneumoniae (certain type of pneumonia) -Gram Negative Gram's stain washes away (cell wall more complex) Neisseria meningitidis (causes meningitis) Escherichia coli (E-coli)--> comes from feces Salmonella enteritidis (salmonella) -Enzymes Can damage "host" cells and tissues -Endospores (some bacteria) Can survive all sorts of temperatures Bacteria duplicates DNA within Resistant coat forms around DNA copy Adverse conditions (heat, chemicals) kill bacteria But spores survives Spores cannot reproduce Vegetative state→ return as bacteria Vegetative cells can reproduce Examples: tetanus and botulism general structure: unicellular (sing-celled) that do not require living tissue to survive * an outer rigid cell wall that provides a specific shape and contributes to its pathogenically walls * a cell membrane that is located inside the bacterial cell wall in gram-positive organisms and on both sides of the gram-negative organisms (controls movement of nutrients) * an external capsule or a slime layer (outside the cell wall in gram positive bacteria) * one or more rotating flagella attached to the cell wall * pili or fimbriae are tiny hair-like projections found on the gram negatives * bacteria contain cytoplasm (exchange genetic info with other bacteria) secrete toxins/toxic substances * can form endospores (latent form of bacteria with a coating that is highly resistant to heat and adverse conditions) bacteria duplicate by binary fission (cells produce two daughter cells identical) major groups of bacteria: bacilli (rod-shaped)--> include vibrio; spirals (spriochete contains and axial filament and the spirilla has flagella)-> cell movement; cocci (spherical forms)
locations, advantages, and disadvantages of resident (normal) flora
-Strains of strep, staph, and fungi exist normally in and on the body * Found on skin, upper respiratory tract, digestive tract * lungs , bladder, stomach, blood, CSF, are sterile -Can become infectious in other locations of the body -Can manifest as an opportunistic infection in an immunocompromised individual * Cancer patients are getting chemo and depletes immune system (immune cells are depleted) → infect them and hurt the tissues -areas of the skin such as the nasal cavity and mouth have resident population of mixed microorganisms (primarily bacteria) -lungs, brain, blood, bladder and kidneys LACK resident flora -great benefit to the host in the synthesis of vitamin K and in some digestive processes -microbes are not pathogenic under normal circumstances but may cause disease if they are transferred to another location in the body (if balance in among the species is not maintained) -or if the body's defenses are impaired -- opportunistic (immunodeficiency states) -usually helpful in preventing other organisms from establishing a colony -skin (blood and CSF fluid) -nose and pharynx (lungs) -mouth, colon, and rectum -vagina (uterus and fallopian tubes) -distal urethra and perineum (bladder and kidney)
Anaphylaxis effects
1. second exposure to antigen 2. antigen binds with IgE antibodies 3. mast cell releases large amount of histamine into general circulation 4. vasodilation and inc. cap. perm.; nerve endings irritated; constriction of bronchiples 5. severe o2 deficit to the brain
fungi
A kingdom made up of nongreen, eukaryotic organisms that have no means of movement, reproduce by using spores, and get food by breaking down substances in their surroundings and absorbing the nutrients Reproduce by spores or budding and extending hyphae Usually part of normal flora Usually thrive in warm, moist body locations -Usually "Tinea" denotes fungus followed by name for body part *Tinea pedis - athlete's foot --> fungus invading the superficial layers of the skin * Tinea cruis - jock itch *Tinea unquium - toenail fungus * Tinea capitus - scalp fungus -Other fungi typically seen in immunosuppressed patients *pneumocystis carinii - causes AIDS pneumonia *candida albicans - causes candidiasis--> infection in oral cavity (Candida albicans is an opportunistic pathogenic yeast that is a common member of the human gut flora. It can also survive outside the human body. It is detected in the gastrointestinal tract and mouth in 40-60% of healthy adults) -Yeast & molds Spores are common means of reproduction Can you think of a common mold? Dermatophytes infect surface of skin *Such infection is called dermatophytosis *Also the nails/skin under the nails -Ringworm (most common dermatophytosis) Tinea species—named according to site (fungal infection) * Ex: tinea pedis (ringworm infection on foot) Very contagious—particularly among children Like dark/damp areas Outer ring of redness/inflamed tissue Tinea pedis (athlete's foot) Thrives in humid areas Bare feet susceptible -Tinea unguium (nails) *Left untreated can damage nails -Tinea cruris (jock itch) -Candida albicans *Aka thrush *Causes candidiasis (yeast infection) → messed up natural flora (things that live on us and bacteria that helps us) -found everywhere on animals, plants, humans and foods classified as eukaryotic and consist of single cells or chains or cells which can forma variety of structures -long filaments or strands of fungus are hyphae (which intertwine to form a mass called mycelium-- the visible mass) reproduce by budding, extension of hyphae, or producing various types of spores -spores can spread easily though the air and are resistant to temp changes and chemicals
obligate parasite
A parasite that obtains its nourishment by living in or on another organism. a virus is a very small obligate intracellular parasite that requires a living host cell for replication
gram stain
A staining method that distinguishes between two different kinds of bacterial cell walls. provides a means of identifying and classifying bacteria useful for selecting appropriate antimicrobial therapy targeting cell wall and structure is important b/c human cells do not have cell walls a stain for bacteria that differentiates the cell walls of gram positive bacterial from that of gram negative; used for identification and choice of drug treatment
endotoxins
A toxic component of the outer membrane of certain gram-negative bacteria that is released only when the bacteria die. a toxin released from the walls of certain gram - bacteria after lysis When they die they release toxins Usually gram- Released when bacteria dies Fever, weakness, and even endotoxic shock (bacterial infection=shock, can die→ effects vascular system) are present in the cell wall of gram - organisms and are released after bacterium dies may cause fever and general weakness or have circulatory effects causing increased capillary perm loss of vascular fluid and endotoxic shock
HBV (hepatitis B virus)
A virus that is transmitted through blood and other bodily fluids that causes inflammation of the liver. Hepatitis B is a viral infection that attacks the liver and can cause both acute and chronic disease. The virus is most commonly transmitted from mother to child during birth and delivery, as well as through contact with blood or other body fluids.
Describe the mechanism and clinical effects of each of the four types of hypersensitivity reactions
Allergic reactions Inflammatory response to harmless substances stimulate an inflammatory response type I: hay fever, anaphylaxis, igE bound to mast cells; release of histamine and chemical mediators; immediate inflammation and pruitus (itching) type II: ABO blood incompatibility; IgG or IgM reacts with antigen on cell-complement activated; cell lysis and phagocytosis type III: autoimmune disorders; systemic lupus, erthematosus, glomerulonephritis; antigen-antibody complex deposits in tissue-complement activated; inflammation, vasculitis type IV: contact dermatitis: transplant rejection; antigen bind to t lymph, sensitized lymp. releases lymphokines; delayed inflammation
Describe the mechanisms of action of common antimicrobial drug
Antimicrobial Drugs Classification: Antibiotic Derived from organisms—ex: penicillin Antibacterial (DOES NOT WORK ON VIRUSES) Works against bacteria (different organisms causing disease) Penicillin -kill or inhibit the growth of microorganisms Antimicrobial Unique to microbes—bacteria, virus, fungus -type of microbe against which the drug is active Bactericidal Destroys bacteria -drugs that kill organisms Bacteriostatic Interferes with bacteria's reproduction -drugs that inhibit reproduction and rely on the host's defenses to destroy organisms Broad Spectrum Works against Gram + and Gram - cell walls (bad for flora) Known to work against a big variety of bacteria -antibacterials that are effective against gram + and - Narrow Spectrum Works against Gram + OR Gram - cell walls (not-so-bad to flora) We think it is this, so we are going to give you this medicine (but if it does not work, broad spectrum) -against either of the grams, but not both -less likely to upset the balance of resident flora in the body First Generation / Second Generation Second generation developed after microbes have gained resistance to first -first gen. is the original drug class -second gen. to a later/improved version of the same drug group -Antimicrobial Drugs: Modes of Action and Considerations Antibacterial Wreck your natural flora Interferes w/cell wall synthesis (penicillin) Increase cell wall permeability (polymyxin) Dangers: Allergies Diarrhea (intestinal flora destroyed) Fungal infections (floral balance destroyed) Antiviral Interfere with viral reproduction in host cell Interfere with viral production in cell (cannot get inside of the cell) Dangers: Interacts with host cells Anti-fungal Increase fungal membrane permeability Usually applied topically -increased use of antimicrobials has resulted in resistance of many organisms to certain drugs -Antibiotics are intended for bacterial infections • "Broad spectrum" affects Gram + and - bacteria. • Don't work on viruses • Bacteria that survive antibiotics reproduce and are resistant to the antibiotic -through mutations, drug resistance has developed in several ways (block drug action) acute infection --> loading dose is admin. -antiviral agents do not destroy the virus but they inhibit its reporduction and provide and opp. for host defenses to remove the virus -antibacterial agents (antibiotics) are not effective against viruses -superinfection: new infection that arises while treating another infection typically involves a different organism and one that is antibiotic resistant
Differentiate between the effects of atopy and anaphylaxis.
Atopy is a local allergic response that runs in families Anaphylaxis is a dangerous systemic allergic response atopy: hypersensitive or allergic state involving an inherited predisposition; inherited tendency to hypersensitivities anaphylaxis: Life threatening allergic reaction Anaphylactic-atopic allergy (IgE-mediated response) Atopy is a syndrome characterized by a tendency to be "hyperallergic". A person with atopy typically presents with one or more of the following: eczema (atopic dermatitis), allergic rhinitis (hay fever), or allergic asthma. Anaphylaxis causes your immune system to release a flood of chemicals that can cause you to go into shock — your blood pressure drops suddenly and your airways narrow, blocking breathing. Signs and symptoms include a rapid, weak pulse; a skin rash; and nausea and vomiting
Discuss the mechanism of autoimmune disorders
Body's own attack upon itself No recognition of body's cells as its own ('self antigen') Body produces "autoantibodies" in response to "autoantigen." Unknown cause of autoimmune disease no longer recognize HLA (produce autoantibodies to yourself to respond to your own self antigen) Cardiovascular system-(rheumatic fever-- strep virus, pernicious anemia) Endocrine disorders-(Type I juvenile diabetes mellitus) Musculoskeletal-(rheumatoid arthritis) Kidney-(acute glomerulonephritis) Multi-system-(lupus erythematosus) occurs when the immune system cannot distinguish between self and nonself antibodies to their own cells when self tolerance is lost, the immune system is unable to differentiate self from foreign material
chlamydiae
Cannot make their own ATP --> obligate intracellular organisms Cause mucosal infxns Chlamydial cell wall is unusual in that it lacks muramic acid Cell cycle w/ 2 forms: elementary body and initial/reticulate body Primitive bacteria Obligate parasite Has infectious EB and reproductive RB -Have two parts : obligate organism (need to get inside a cell to survive) Two forms of bodies -Primitive bacteria Behaves somewhat like viruses in host cells obligant→ needs to be inside of cells to reproduce Responsible for chlamydiosis (common STD) -considered primitive forms related to bacteria that lack many enzymes for metabolic processes -exist in two forms : elementary body (EB) which is infectious and processing a cell wall and the ability to bind to epith. cells; other form is reticulate body (RB) which is noninfectious but uses the host cell to make ATP and reduce as an obligate intracellular organism -RBs change into EBs (rupturing the host cells membranes and dispersing to infect more cells) -matority disease and sterility in women -may develop eye infections or pneumonia
Describe examples of resistant microbes
Clostridium difficile ("c-diff) -Elderly -Bacteria (from the intestine infection) → transmitted through fecal matter -Fecal transplant (return natural flora back to normal) -Inflammation of the colon caused by the bacteria Clostridium difficile. -disruption of normal flora and it multiplies and causes severe diarrhea and many deaths MRSA -Methicillin-resistant staphylococcus aureus Resistant to methicillin - community not just hospital -An infection caused by bacteria commonly found on the skin or in the nose. VRE -Vancomycin resistant enterococci (VRE) -Vancomycin-resistant enterococci (VRE) are a type of bacteria called enterococci that have developed resistance to many antibiotics, especially vancomycin. ... But if they become resistant to antibiotics, they can cause serious infections, especially in people who are ill or weak
List the components of the immune system and the purpose of each
Complement Inactive proteins → become activated; go through cascade Activated by IgG or IgM antibodies Types C1 through C9 Proteins When activated by C1 binding with antibody: "Cascade" of activation occurs with the other 8. Results in either lysis of invading antigen or marking of invader for lysis. Initiates inflammatory response. **The complement system is a part of the immune system that enhances (complements) the ability of antibodies and phagocytic cells to clear microbes and damaged cells from an organism, promote inflammation, and attack the pathogen's cell membrane** Membrane attack complex → becomes very destructive (immune system uses this → attacking itself; protein lights up); sometimes it misfires Chemical Mediators (support damage, works in tandem w/ inflam. response) Includes: Histamine (capillary perm) Kinins Prostaglandins (prolongs effect) Leukotrienes Cytokines (chemical messenger) Tumor necrosis factor (TNF) Chemotactic Factors Many jobs... Signal cell response Damages invader Lymphoid Structure Lymph nodes → little filters that contain lymphocytes (monitoring) Lymph system → returns fluid and protein to circulatory system and inspect the fluids Spleen → blood gets returned and recycled ; lymphocytes monitoring Tonsils → pharyngeal and palatine → things coming (what is going on inside of you) Immune Cells Lymphocytes Tissues to develop immune cells Bone marrow → produces lymphocytes Thymus → T cells ; where you are an infant (body is teaching itself what itself is→ major histocompatibility) Antigens → something (protein, molecules, glycoprotein; outside of the cell) it is a marker; all living things have microbes (antigens) → body naturally develops type b antibodies to type a antigens Identifies it (if something is you or foreign) Cells → cells like macrophages; immune system uses inflam. Response in fighting off invaders Antibodies or Immunoglobulins → IG; Complement System Chemical Mediators → uses some mediators to take care of invaders Lymphatic vessels contain lymph—a clear, slightly yellow liquid containing lymphocytes—which is returned to the blood circulation Antigens Based on inherited major histocompatibility complex (MHC) Self antigen on the surface of the cell Helps control and regulate immune system/cells talking to each other MHC is what makes us unique and is crucial to intracellular communication. MHC is also known as Human Leukocyte Antigen (HLA)—used to determine "close" matches for transplants. Human leukocyte antigen (HLA) → transplant tissue matches Other microorganisms and substances have there own antigens and are identified as "non-self." "Non-self" antigens invading Cells Macrophages Monocytes—part of mononuclear phagocytic system (formerly known as reticuloendothelial system) They are eating things Lymphocytes T-Lymphocytes (Cell-Mediated Immunity) Cytotoxic CD8-positive T- Killer cells -> identify foregin antigen and inject/attack the enzyme (DESTROY WHATEVER IT IS) The remember what they killed → good at virus, fungi, protozoa Helper CD4-positive T-Cell Includes memory T cells in lymph nodes Notify the B lymphocytes (where you get antibodies) B-Lymphocytes (Humoral Immunity) "Plasma" from produces antibodies Fight off invaders "Memory" cells provide for antibody production later Identify foreign body and become plasma cells → matches up the antibody and divides, makes memory cells, and plasma cells (which actually make antibodies) Antibodies (Y shaped), find a place where they can attach, and stick on the antigen Natural Killer (NK) cells Neither T or B, go after tumor & virus-infected cells Like macrophages; will kill anything foreign (goes after cancer cells) Antibodies (Immunoglobulins) (Antibody binding to an invading antigen) Not all stick to antigen; must match up to marker It might take awhile; has unlimited variation
infection
Contamination or invasion of body tissue by pathogenic organisms -occurs when a microbe or parasite is able to reproduce in or on the body's tissues -infection→ microorganisms living on you and is starting to cause you diseases/damage A colonized organism is having adverse effects on body tissues (causing disease) → once it starts hurting tissues, it causes infection
Type II: Hypersensitivity: cytotoxic hypersensitivity
Cytotoxic hypersensitivity Antigen binds to blood cells or is present IgG Antibodies attach to antigen Antigen-antibody complex activates other factors (complement) Cell is lysed by antibody or other complement factors This happens with incompatible blood transfusions antigen is present on the cell membrane-- may be a normal body component or foreign causing destruction of the cell by phagocytosis destroy membrane of cell-- cell is lysed incompatible blood transfusion 1. anti a antibodies in type b blood mix with type a blood and attach to 2. target cell with surface antigen 3. complement activated 4. lysis of cell wall of RBC-- type a 5. phagocytosis type O --> universal donor involves rejection of blood transfusions
Type IV: Hypersensitivity: Cell-mediated (delayed) hypersensitivity
Delayed cell-mediated hypersensitivity Directed by cells (T lymphocytes & macrophages) Just like immune response but delayed (12-48 hrs.) Destruction of skin (inflammation) 'contact dermatitis' (often hours after the exposure) Also: TB Test Transplant rejection 1. macrophage presents antigen 2. sensitization of t lymph 3. release of lymphokines 4. inflammation and lysis 5. tissue destruction contact dermatitis (allergic skin reaction)-- contact with a chemical latex sensitivitiy delayed directed by the T cells contact dermatitis
gram positive
Describing the group of bacteria that have a cell wall that is structurally less complex and contains more peptidoglycan than the cell wall of gram-negative bacteria. Gram-positive bacteria are usually less toxic than gram-negative bacteria. Gram positive bacteria have a thick peptidoglycan layer and no outer lipid membrane whilst Gram negative bacteria have a thin peptidoglycan layer and have an outer lipid membrane
gram negative
Describing the group of bacteria that have a cell wall that is structurally more complex and contains less peptidoglycan than the cell wall of gram-positive bacteria. Gram-negative bacteria are often more toxic than gram-positive bacteria. Gram positive bacteria have a thick peptidoglycan layer and no outer lipid membrane whilst Gram negative bacteria have a thin peptidoglycan layer and have an outer lipid membrane
Pandemic
Disease that occurs over a wide geographic area and affects a very high proportion of the population. -a worldwide increase in the numbers of people affected by a disease
Describe the course, effects, and complications of HIV-AIDS
HIV is not transmitted by casual contact, sneezing, or coughing AIDS develop: Destruction of T lymphocytes HIV infects CD4 T-helper lymphocytes Virus replicates in T cell T cells die and HIV buds out to infect more T cells Monocytes & Macrophages hold and transport HIV to other sites talk w/ the b and t cells -- transmit info AIDS suppression of immune system: T4 Lymphocytes help B-cells transform into plasma cells and make antibodies, so... Body can't recognize antigens Decreased B cell activation Decreased antibody production Decreased macrophage response Decreased killer T cell activity AIDS Complications: Kaposi's sarcoma Chronic candidiasis (white plaques) Necrotizing periodontal dz treatment: Antiviral drugs AZT the best known (azidothymidine) Drug cocktail Combination of three to five drugs Prolongs latent phase & decreases virus load in final phase Long-term effect unknown Highly Active AntiRetrovirus Therapy (HAART) Often given to pregnant women Follow Universal Precautions! Dispose of Sharps Properly Do not recap! Always wash hands between patients Wear PPE (Personal Protective Equipment) Gloves Goggles Masks if risk of splattered blood superconversion: -window period -virus in blood -no antibodies -mild symptoms HIV +: -more antibodies form -small amts of virus in blood -asymptomatic AIDS: -active infection -decreasing cd4 count aids idication disease (dementia) -nucleic acid test is used to confirm HIV-1 and HIV-2 antibodies -secondary infections are common with aids and are primary cause of death -- drug treatments are ineffective -brain: memory loss, confusion, dementia, infections, lymphoma -mouth, esophagus: candidasis, herpes simplex -lymphadenopathy: generalized -lungs: pneumocytosis carinii TB -GI: chronic diarrhea, infection, wasting anorexia - skin: dermatitis, infections, kaposi sarcoma -blood: viremia-HIV; decreasing count of helper t lymph -AIDS is an example of HIV and destroys t helper lymphs, preventing humor and cell mediated immunity -- antibodies are present in the blood -HIV is transmitted by blood, tissues, or sexual contact and is transmitted by infected moms to infants
List the factors determining host resistance (Mainly know situations that decrease host resistance)
HOST→ organism the other organism picks up **Host—another living organism providing a living environment for the pathogen** -Factors decreasing host resistance Age (infants and elderly) Genetic susceptibility Immunodeficiency of any type Malnutrition Chronic diseases (including cardiovascular disease, cancer, diabetes) Severe physical or emotional stress * Steroids depletes immune system * Stress makes the immune system go down Break down of skin by inflammation or trauma impaired inflamm. response: ex-- Long term glucocorticoid use -inflammation or trauma affecting the integrity of the skin or mucosa (including burns, lacks of protective secretions, bladder catheters, or any invasive procedures) -host resistance: *intact skin and mucous membrane *body secretions -- stomach acid and tears * nonspecific phagocytosis * effective inflammatory response *absence of disease * effective immune system * interferon production (virus) -interferons are proteins by human host cells in response to viral invasion of the cell * also stimulate the immune system and are used in cancer treatment
Staphyloccus aureus
Humans and animals are reservoirs. Present in the nose and in skin lesions Elaborates a toxin that is resistant to high temperatures Causes a foodborne intoxication with rapid onset Ham is a frequent vehicle Staphylococci: spherical clusters Staphylococcus aureus (MRSA)--> resistant form (found in the skin and outer part of respiratory tract) Staphylococcus aureus (strep)
Type I: Hypersensitivity (allergic reactions)
IgE mediated Anaphylactic-atopic allergy (IgE-mediated response) Immediate hypersensitivity (on 2nd + exposures) Inflammatory response to allergens (dust, pollen, animal dander) Histamine is produced (so you take an .....?) Other responses: food and drug allergies Hives, pruritis, tingling, warmth, vomiting Anaphylaxis, dyspnea, shock, weak pulse, dizzy!!! Atopy is local. Anaphylaxis is systemic-- happens rapidly (type 1) Anaphalaxis: emergency treatment Epinephrine injection People who are known to be susceptible to allergies often carry an "epi pen." manifestation of such an allergy in a family is atopic causative mechanism: -IgE antibodies from b lymph. -antibodies attach to mast cells -chemical mediators cause brinchoconstriction clinical signs and symptoms: -second exposure to the specific allergen b/c the first exposure only causes formation of antibodies and sensitized mast cells -vesicles or blisters are present -pruitic area (itchy) hay fever-- sneezing (nasal mucosa) food allergies atopic dermatitis or eczema asthma (lung disorder) anaphylaxis-- reaction resulting in decreased blood pressure, airway obstruction, and severe hypoxia (itching or tingling sensation, coughing, hard time breathing, weakness, dizziness, fainting ) decreased blood pressure CNS-- anxiety and fear (loss of consciousness) treatment: epinephrine injection
Type III Hypersensitivity: immune complex hypersensitivity
Immune complex-mediated hypersensitivity Antigens flowing in blood stream Antibodies attach to antigen Sticks to blood vessel walls Complement destroys the cells & area Causes acute vasculitis and thrombosis This can be localized or systemic Also common in joints & kidneys (glomerulonephritis) antigen combines with antibody forming a complex (activates complement) causes inflammation and tissue destruction serum sickness: systemic reaction that occurs when immune complex deposits occur in many tissues arthus reaction is a localized and tissue necrosis that results when an immune complex lodges in the blood vessel wall, causing vaculitis farmers lung strep infections thrombocytes -- platelets
antibodies
Immunoglobulins produced by the immune system in response to bacteria, viruses, or other antigenic substances. has a sequence of amino acids and is attached to a common base bind to specific matching antigen, destroying it Antibodies (Immunoglobulins) (Antibody binding to an invading antigen) Not all stick to antigen; must match up to marker It might take awhile; has unlimited variation Antibodies and Immunoglobulins IgG Most common in blood IgM First to increase in immune response IgA In secretions Tears Saliva and mucous membranes Colostrum IgE Allergic response Causes release of histamine and other chemicals Results in inflammation Reacting to things they shouldn't be reacting to IgD Attached to B cells Activates B cells found in general circulation, forming gamma region of plasma proteins x
mycoplasmas
Lack cell walls Sterols in plasma membrane Smallest cellular microbe Considered bacterial but no cell wall Cause atypical pneumonia -Tiniest of cellular microbes Mycoplasma pneumonia Primitive bacteria Actual cells/living things -infection which is a common cause of pneumonia these microbes lack cell walls and therefore are not affected by many antimicrobial drugs and they can appear in many shapes they are the smallest cellular microbes
Define MHC (HLA) and antigens
MHC (HLA): -Antigens Based on inherited major histocompatibility complex (MHC) -MHC is what makes us unique and is crucial to intracellular communication. MHC is also known as Human Leukocyte Antigen (HLA)—used to determine "close" matches for transplants. -HLA (or MHC) Typing → human leukocyte (matching tissues/cells) To match transplant donors to recipients (diagnostic testing) -Human leukocyte antigen (HLA) → transplant tissue matches -antigen molecules are coded by a group of genes inherited from the parents (MHC) located on chromosomes -activation and regulation of the immune response and intercellular communications -detecting changes in cell membranes altered by viruses -tolerates self antigens * autoimmune diseases are an exception in which the immune system no longer regonizes self from non self and attacks its own cell antigens: -Antigens → something (protein, molecules, glycoprotein; outside of the cell) it is a marker; all living things have microbes (antigens) → body naturally develops type b antibodies to type a antigens Identifies it (if something is you or foreign) -Antigens Based on inherited major histocompatibility complex (MHC) Self antigen on the surface of the cell Helps control and regulate immune system/cells talking to each other -Antigen stimulates Helper T which with the antigen stimulates B cell which becomes mother of clones -immunogens (foreign substances or human cell surface molecules that are unique) in each person -composed of complex proteins (glycoproteins) -activate the immune system to produce specific antibodies -represent self (plasma membranes) -foreign substance, microbes, or component of cell that stimulates immune response
Describe the methods of transmitting microbes and know examples of each
MODES of transmission Direct Lesion-to-lesion, blood to blood no intermediary such as touching an infectious lesion or sexual intercourse Indirect Hand, food, or fomite involving an intermediary such as a contaminated hand or food or a fomite (carries organisms) Droplet Respiratory excretions or oral occurring when respiratory or salivary secretions containing pathogens such as tb bacteria are expelled from the body inhaled directly or transmitted indirectly Aerosol On small particles exiting the respiratory tract involving small particles from the respiratory tract that remain suspended in the air and travel on air currents, infecting any new host who inhales the particle Vector-borne Insect or animal Bats or bugs Reservoir insect or animal serves as as an intermediary host in a disease such as malaria Hands!! (lack of proper hand sanitization)
definition
Microorganism - living, cannot be seen with naked eye Pathogen - causes disease. Host—another living organism providing a living environment for the pathogen Vector—A living organism that infects another living organism with a pathogen Fomite—Inanimate object that harbors a pathogen Normal flora- normally inhabit body Don't hurt us; usually helps us Inside our digestive tract that we need malaria→ breathing bad air (vector: mosquitos, ticks, insects): A disease caused by a plasmodium parasite, transmitted by the bite of infected mosquitoes. infection→ microorganisms living on you and is starting to cause you diseases/damage virion→ virus located outside of the cell (outside of the host cell)
colonization
Organism is reproducing and conducting its life processes -colonization is the presence of bacteria on a body surface (like on the skin, mouth, intestines or airway) without causing disease in the person
Streptococcus pyogenes
Penicillin prophylaxis Cocci-spherical Streptococcus pyogenes (usually caused strep throat) Streptococcus pyogenes causes over 700 million infections globally every year and has a high mortality rate of 25 per cent in serious cases - once you have an infection the bacteria can cause a range of diseases ranging from sore throat and impetigo up to scarlet fever.
Explain the causes and effects of the various types of immunodeficiency
Primary deficiencies Developmental failure Stem cell production in bone marrow Thymus Antibody production Secondary (or acquired) deficiencies Infection Splenectomy Liver disease In response to treatments (iatrogenic) Corticosteroids Chemotherapies Radiation Inherited immunodeficiencies involve either humoral (agammaglobulinemia) or cell mediated (thymic hypoplasia) immunities or both (severe combined immunideficiency or SCID) effects: Prone to opportunistic infections May develop infections from organisms that are part of the bodies natural flora Increased incidence of cancer treatment: Antibody replacement (gammaglobulin injections) Prophylactic antibiotic administration Bone marrow or thymus transplants (Very limited success) CAUSES: -results from loss of function -primary deficiences involve a basic developmental failure somewhere in the system -secondary/acquired immuodef. refers to loss of the immune response resulting from specific causes -viral infection (splecetomy: removal of spleen) and hypoproteinemia (low serum protein leve) -associated with cancer (malnutrition and blood loss) -aids and hiv infection (affecting t-helper cells) EFFECTS: -predisposes pts to the development of opportunistic infections -arise from resident flora -antibiotics administered
Artificial active immunity
Production of one's own antibodies or T cells as a result of vaccination against disease Active (antibodies produced by "host" organism) → make your own antibodies Artificial → get a shot of some sort Vaccination using non-disease causing organisms to generate primary response and antibody memory. When we get the flu shot / flu vaccination of flu shot with flu antigens develops when a specific antigen is purposefully introduced into the body, stimulating the production of antibodies vaccine is a solution containing dead or weakened organisms that stimulate the immune system to produce antibodies but does not result in the disease itself vaccine (live or attenuated organisms) is injected into the person; no illness results, but antibodies form, there is memory; persona has measles vaccines and gains immunity
Describe the normal immune response
Purpose: specific defense The immune response which include cell-mediated and humoral immunity Work together The immune response: Distinguishes "self" from "non-self." Identifies specific threats. Produces a specific response. Remembers the threat and prepares for future encounters with the same threat. Limits the response to avoid harm to healthy tissues. Controlling immune response → when to stop in immune response (tells us who we are) Immune system targets specific threats (what belongs and what does not) -detect and destroy unknown material -demonstrates tolerance -develops a specific response to that particular antigen and stores that particular response in its memory cells -specific immunity (antibodies) -immune system plays a role in preparing injured tissue for healing -indiiv. develop cancer when the immune system is depressed as with an infection or increased stress
secondary immunodeficiency
Secondary (or acquired) deficiencies Infection Splenectomy Liver disease In response to treatments (iatrogenic) Corticosteroids Chemotherapies Radiation secondary: refers to loss of immune response resulting from specific causes and may occur at any time during the lifespan -- can occur with infection
Borrelia burgdorferi
Spirals (spirochetes) Lyme disease Borrelia burgdorferi (Lyme disease) → carried by the tick (bacteria gets into joints)
Antivirals are intended for viral infections
Tamiflu is an example -limit viral replication and reduce active stage antiviral agents can decrease the reproduction of viruses inside the host cell or prevent its attachment entry into a cell, but typically cannot destroy the virus -control but do not cure the infection -genomics is the basis for several new types of antiviral drugs -antifungal agents may interfere with mitosis in fungi or they may increase fungal membrane perm. -antiprotazoal agents have similar charac. to antifungal in that the targets are eukaryotic cells and can be toxic to human cells -antihelminthic agents attack eukaryotic organisms (suppress metabolic process) "Self-limiting," Some antivirals if taken very early (Tamiflu) -Antiviral Interfere with viral reproduction in host cell Interfere with viral production in cell (cannot get inside of the cell) Dangers: Interacts with host cellsanti
Describe the respiratory infection influenza, including the cause transmission, immunization, manifestations, possible complications, and why we have to get flu shots every year
Types A, B, & C (Novel H1N1 is Type A) Undergoes constant "antigenic" shifts Transmission By droplet—direct and indirect (@#* fomites!) Upper Respiratory infection (more systematic than cold) Infection Inflammation/necrosis of respiratory mucosa Signs/Symptoms fever, chills, malaise, fatigue, head/muscle aches, nasal congestion Treatment "Self-limiting," Some antivirals if taken very early (Tamiflu) Complications Secondary infection due to bacterial chowing on necrosis Shot every year because different strands develop (slice up DNA and come together→ over time they mutate) Antigenic drifts (changes gradually) → person to person it gradually changes Antigenic shift → SHIFT (person to animal, then back to people Influenza 101 Influenza types A & B comprise seasonal flu Types A, B, and C are orthomyxoviruses (RNA). Influenza A is divided into subtypes: Ex: A(H1N1) and A(H3N2). The H is for Haemagglutinin protein There are 16 different types of Haemagglutinin proteins. The N is for Neuraminidase protein There are 9 types of Neuraminidase Proteins Influenza B has not subtypes but has different strains. Influenza C causes mild respiratory illness but no epidemics -influenza is a viral infection that may affect both the upper and lower respiratory tracts -classified as RNA viruses -type a undergoes frequent mutations leading to antigenic shifts or variations (limits the ability of individuals to develop long-term immunity to the virus and requires the preparation of new vaccines each year to match the predicted new strains of the virus for the coming year) -vaccine may be admin. by intranasal spray or IM injection -- reduces severity of infection (virus can survive room temp for at least 2 weeks) -destroyed by heat and disinfectants -virus enters the cell in the respiratory mucosa, replicates, and causes inflammation and necrosis of the tissue as well as shedding of the virus into the secretions and adjacent cells -infection is self limiting -secondary bacterial infections such as penumonia are common
Discuss tissue transplant rejection and how it's treated
Understand how this can lead to opportunistic infections Success more likely with close HLA matches Rejection: Type IV Hypersensitivity (next part) Antibodies attack graphed tissues Types Host vs. Graph Disease (HVGD) Graph vs. Host Disease (GVHD) Hyperacute (immediate) Acute (in a few weeks) Chronic (after months or years) Avoiding rejection Immunosuppressive drugs used Cyclosorine, Imuran, prednisone Prone to opportunistic infections and some cancers Corneas and cartilage don't have blood vessels Therefore rejection doesn't happen with these Newborns and young infants have undeveloped immune systems Seem more receptive to higher HLA differences -involve introduction of foreign tissue from one human, the donor, into the body of the allograft (recipient) -rejection process destroys the organ -rejection does no occur b/c the infant's immune system is not yet mature and does not respond to foreign tissue -host's immune system rejects the graft -graft tissue contains t cells that attack the host cells (occur in bone marrow transplants) -hyperacute rejection acute occurs immediately after transplantation as circulation to the site is reestablished -acute rejection develops after several weeks when unmatched antigens cause a reaction -chronic or late rejection occurs after months or years (degeneration of the blood vessels)
Discuss methods of preventing and controlling infection
We need to break the chain MMR comes in (vaccination works for about 70 percent) Control the reservoir and get people vaccinated (reservoir is not developed → HERD IMMUNITY) → vaccinate enough, so the disease will NOT transfer Links of the chain Microorganism → host Host → reservoir Reservoir → new host Prevent transmission to transmission HAND WASHING Cleaning things (ex: food handling) -glove and appropriate apparel are used to reduce the tranmission of organisms in either direction -break cycle/minimize the risk of infection * reservoir or source of infection must be located and removed and sources and contacts * contaminated food or water or carrier food handlers * can be transmitted before clinical signs are evident in the infected person (permits widespread contamination) * infected travelers should refrain from travel to prevent spreading disease * portal of exit (secretions) should be blocked from reservoir * knowledge of modes (portals of entry and exit should be blocks, host susceptibility)
hypogammaglobulinemia
a below normal concentration of gamma globulin in the blood associated with a decreased resistance to infection low antibody levels because of a B-cell defect or a developmental defect known as DiGeorge syndrome (hypoplasia of the thymus) The most common causes worldwide include malnutrition, poor sanitary conditions and human immune deficiency virus (HIV) infection
antigenic drift
a mechanism for variation in viruses that involves the accumulation of mutations within the genes that code for antibody-binding sites. -Antigenic drift→ changing (slight change from person to person→ in genetic makeup the RNA; but enough changes that your body has enough immunity) Antibodies do not fully recognize it; disease is not fully as bad Dangerous mutation Antigenic drift is a mechanism for variation in viruses that involves the accumulation of mutations within the genes that code for antibody-binding sites Both antigenic drift and antigenic shift are terms used to describe ways in which the flu virus changes over time. A drift is a minor change while a shift is a major one.
WBC count
blood tests are another indication of infection Blood tests High WBC count CBC blood count → clues to what kind of infection goes on A lot of viruses deplete WBC count leukocytosis and leukopenia (reduction of the number of leukocytes in the blood) blood tests are useful for indicating and detecting antibodies and confirming a diagnosis (in case of viral infection) A white blood cell (WBC) count is a test that measures the number of white blood cells in your body. This test is often included with a complete blood count (CBC). The term "white blood cell count" is also used more generally to refer to the number of white blood cells in your body.
septicemia (sepsis leading to septic shock)
caused by multiplication of pathogenic organisms in the blood and the cause of sepsis, a toxic inflammatory condition arising from the spread of microbes -Generalized or systemic infection in bloodstream Infecting agent into the bloodstream and spreading all over the body → LIFE THREATENING The body cannot fight it off → NEEDS medical attention Very serious/potentially deadly (~ 1 million cases/yr) -Septicemia-multiplying pathogens in blood→ living in the blood -Septic shock Mortality rate: ~45% failure of circulatory system due to toxins in blood insufficient perfusion (lose blood pressure and cells die because not enough o2) body's reaction: Vasodilatation → causes problem Tachycardia --> make up for lack of BP / heart is just racing
See Figure 7.2 on p. 116
cell mediated immunity 1. lympho blasts (bone marrow stem cells) 2. thymus 3. t cells 4. migrate to lymph nodes 5. antigen stimulation 6. various types of sensitized t cells in circulation (helper t, memory t, suppressor t. cytoxic t) humoral or antibody mediated immunity 1. lympho blasts (bone marrow stem cells) 2. bone marrow 3. b cells 4. migrate to lymph nodes 5. antigen stimulation 6. antibody -- memory b cells
Endemic
confined to a particular country or area -a disease that is always present in a specific area -certain infections that are consistently occurring in that population
Virulence
degree of pathogenicity -a microorganism's degree of pathogenicity (if something does cause a disease, what is the degree of intensity/pathogenicity?) * How bad can it cause the disease * Invasive qualities (allowing it to directly damage the host cells and tissues and spread) * Toxic qualities (production of enzymes, exotoxins, and endotoxins that damage host cells or interfere with a host function such as nerve conduction) * Adherence to tissues (fimbriae, capsules, or specific membrane receptor sites. certain organisms tend to establish infection in certain areas of the body considered hospitable to that microbe) --Ex: pili that sticks to tissues * Ability to evade/avoid the body's defenses (presence of a capsule or mutation with altered antigenicity) -- undergo frequent mutation (changes= individ. is no longer protected) -- Mutate -- Bacteria and viruses change (body tries to identify it) → keeps reproducing and CHANGING (happens w/ bacteria) -degree of pathogenicity of a specific microbe -often expressed in the case fatality rate (% of deaths occurring in the number of persons who develop the diseases)
spores and vegetative form
endospore: latent form that certain bacteria can assume under adverse conditions, in order to survive extreme temps, drying, or chemicals Endospores (some bacteria) Can survive all sorts of temperatures Bacteria duplicates DNA within Resistant coat forms around DNA copy Adverse conditions (heat, chemicals) kill bacteria But spores survives Spores cannot reproduce Vegetative state→ return as bacteria Vegetative cells can reproduce Examples: tetanus and botulism Spores are common means of reproduction bacterial endospores --> bacillus species (pink bacilli are vegetative cells and green ovals, both inside and outside of the cells, are endospores.
systemic signs of infection
fever, fatigue, weakness, headache, nausea Migrate all over the body Altered mental status Pyrexia, fatigue, weakness, headache, nausea Sometimes CNS affected * Confusion, disorientation, even seizures and L.O.C. (loss of consciousness) -infection spreads to several sites and tissue fluids, typically through the circulatory system -any area of the body (fever, fatigue, weakness, headache, and nausea)
primary response
first time the immune system combats a particular foreign substance Immunity = no longer susceptible to the disease Natural Immunity = species specific Innate Immunity = gene specific (ethnicity) → gene specific Immune to some diseases than others Primary response Gradual build up of antibodies for defense. Antigen stimulates Helper T which with the antigen stimulates B cell which becomes mother of clones Mother becomes Blast Cell and memory cell for future use Mitosis creates clones Clones mature into Plasma Cells (many, many produced from 1 mother) Clones produce antibodies to antigen (much more than could be produced by original B cell) Get sick -occurs when a person is first exposed to an antigen takes 1 to 2 weeks
H1N1 (typical type A flu virus)
has components from both swine flu and human flu; these mixtures can change rapidly, leading to new combos Swine flu is an infection caused by a virus. ... The virus is contagious and can spread from human to human. Symptoms of swine flu in people are similar to the symptoms of regular human flu and include fever, cough, sore throat, body aches, headache, chills and fatigue.
nosocomial infection
hospital acquired infection infections that occur in health care facilities, including hospitals, nursing homes, and dental offices reasons for these infections include the presence of many microorganisms in these settings, pts with contagious diseases, overcrowding, use of contaminated instruments, immunocompromised and weak pts, the chain of transmission through staff -most infections are transmitted by direct contact c-diff MRSA
Artificial passive immunity
immunity which results from the administration of antibodies from another animal against a dangerous pathogen. Artificial Introducing antibodies from another source to fight disease. Do not make own antibodies; get it in a SHOT contained with a lot of antibodies results from the injection of antibodies from a person or animal into a second person ex: administration of rabies antibodies injected into person (antiserum) to provide temporary protection or minimize severity of infection there is no memory gammaglobulin if recent exposure to microbe (EX)
• incubation period
interval between initial infection and first signs and symptoms Microbes incubate (then they start to damage tissues and getting inflammation) → can be a few days (takes time for signs to show up) refers to the time the body is exposed to the organism and the appearance of clinical signs of the disease. may last for days or months
secondary response
later interactions with the same foreign substance; faster and more effective due to "memory" Some of the clones do not become plasma cells but become "memory" cells Memory cells contain information about the antigen that stimulated its development and remembers it If the antigen is encountered again by a memory T and memory B cells, then the memory B cell produces plasma cells and antibody at a much higher rate Quick/effective response IMMUNITY ACQUIRED! Still get invaded, but do not get sick Secondary Response Quick response and build up of antibodies from "memory." results when a repeat exposure to the same antigen occurs much more rapid and results in higher antibody levels than the primary response
Describe the mechanisms of action of common antimicrobial drug (PT 2)
mode of action: 1. interference with bacterial cell wall synthesis 2. second mechanism is to increase the perm. of the bacterial cell membrane (allowing leakage of bacterial cell contents) 3. some dugs interfere w/ protein synthesis 4. other agents interfere with nucleic acid syth. 5. some agents can disrupt other critical metabolic processes
the autoimmune process
normal immune response: 1. invaders (antigen) 2. antibodies form 3. antibodies remove invading antigens 4. antibody remains for future protection autoimmune disease 1. immune system forms antibody to self-antigens 2. autoantibodies attack self-antigens and immune complexes deposit 3. inflammation and tissue damage occur
protozoa
one-celled organisms that are more complex than bacteria eukaryotic (have nucleus) parasites Live within cell -some examples * Trichomonas vaginalis -Trichomoniasis --> distinguished by its flagella and causes a sexually transmitted infection of reproductive tracts of men and women by attaching to the mucous membranes and causing inflamm. * Plasmodium vivax (also P. falciparum) - Malaria --> temperate climates and found in RBCs where they undergo stages of the life cycle * Entamoeba histolytica -amebic dysentery --> ambea that engulfs food in the same manner--> a parasite in the large intestine that causes ambeic dysentery; a severe form of diarrhea and liver abscesses if it penetrates into portal circulation (TROPHOZITES AND CYSTS) --> Spread by fecal-oral route * Giardia—giardiasis (commonly a water-borne illness)--> GI infections -- consumption of contaiminated food or water ; cyst-forming organisms that is excreted in feces and can survive if ingested by new host -Single-celled, eukaryotic Live inside blood cells No cell wall -Can sometimes change shape *Trichomonas vaginalis Has flagella—causes trichomoniasis (STD) * Plasmodium vivax Malaria Plasmodium falciparum—very virulent * Entamoeba histolytica Amebic dysentery * Giardia Cyst-forming, flagellated protozoan often spread through contaminated water Spread in bad water -Malaria is most common protozoa -usually motile and lack a cell wall and are unicellular -pathogens are usually parasites (infection: trichmoniasis malaria and amebic dysentery) -ambeas are a motile group of protoza, moving by extending part of their cytoplasm and flowing forwar (ambeoid movement)
secondary infection/opportunistic infection
opportunistic infection after a primary (predisposing) infection -follows a primary infection and is caused by a microbe other than that causing the primary infection; opportunistic pathogens are often the cause of secondary infection -Infection that develops because of your first infection (get a cold, and then it goes on for double the amount of time, now you have a bacterial infection) aka 'opportunistic' Additional infection caused by another microbe that usually doesn't cause problems Waits for the 'opportunity' → you are already down, and now some other bug will take over AIDS Immunocompromised An opportunistic infection is an infection caused by pathogens (bacteria, viruses, fungi, or protozoa) that take advantage of an opportunity not normally available, such as a host with a weakened immune system, an altered microbiota (such as a disrupted gut microbiota), or breached integumentary barriers.
local signs of infection
pain, swelling, redness, warmth Inflammation Viral → clear coming from lesion Pus = bacterial infection Exudate Serous—viral source Purulent—bacterial source Tissue necrosis ⇒ tight part of skin on infected area Lymphadenopathy ⇒ lymph nodes get swollen -organism enters the body and remains confined to a specific location -those of inflammation (like pain, redness, tenderness, warmth, swelling)
rickettsiae
parasitic microorganisms that live on another living organism and cause disease usually spread by ticks (vector) Small Gram negative Reside in host cells Use insects as "vectors" (Rocky Mtn Spotted Fever) -tiny gram - bacteria that lives inside a host cell (obligate intracellular parasites) they are transmitted by insect vectors, such as lice or ticks and cause diseases such as typhus fever and rocky mountain spotted fever attack blood vessel walls causing a typical rash and small hemorrhages -Tiny Gram- bacteria - Insect vector transmission * Ex: Rocky Mountain spotted fever through tick bite
helminths
parasitic worms -Worms, usually occupy digestive track * Pin worm - common in U.S. children * Tape worm - more common in developing countries * ascaris (giant roundworms) - Spread through various means * Fecal-oral route * water * insect vectors -Multi-celled, parasitic organisms -Live in three stages: * Ovum, larva, and adult -Found in intestines, blood, other tissues *Not microscopic -worms are not microorganisms by are often included with microbes because they are parasites and cause infections in humans -multicellular and eukaryotic -ovum , larva, and adult - severe anemia can develop (systemic effects)
structures of the immune system
pharyngeal tonsil palatine tonsil lymph nodes-- cervical lymphatic vessels thymus lymph nodes-- axillary spleen lymph nodes-- intestinal bone marrow lymph nodes-- inguinal
bacteremia
presence of bacteria in the blood -Bacteremia—bacteria in bloodstream
primary immunodeficiency
primary: involve a basic develop. failure somewhere in the system in, thymus -result from a genetic or congenital abnormality and noticed by infants **primary deficiencies Developmental failure Stem cell production in bone marrow Thymus Antibody production
chronic infection
progress and persist over a long period of time Septic Affect all tissues and the whole body → can cause you to die Overwhelming infection → Septicemia (death)? Chronic infection Like MRSA -less severe symptoms than acute but persist for a long period
typical signs of infection
redness (erythema) swelling localized heat in injury area increased body temperature pain resulting from excessive pressure on tissue due to -Fever (this is sometimes the only sign of an infection). Chills and sweats. Change in cough or a new cough. Sore throat or new mouth sore. Shortness of breath. Nasal congestion. Stiff neck. Burning or pain with urination.
HPV 1 (human papilloma virus 1)
several strains of this have been shown to be a major cause of cervical cancer and is approved for use in females entering puberty to prevent late cancer HPV infections are so common that nearly all men and women will get at least one type of HPV at some point in their lives. Nearly 80 million Americans are currently infected with some type of HPV. About 14 million Americans, including teens, become infected each year. HPV is spread through intimate skin-to-skin contact. You can get HPV by having vaginal, anal, or oral sex with someone who has the virus.
• prodromal period
short period after incubation; early, mild symptoms Think you are coming down with something, but no symptoms or signs are really distinct Can feel really drained (like night and day) You think you are coming down with something -early symptoms stage when the infected person may fell fatigued, lose appetite, or have a headache and usually senses that "I'm coming down with something"
Humoral immunity
specific immunity produced by B cells that produce antibodies that circulate in body fluids B → humoral immunity (making antibodies); mature in bone marrow B-Lymphocytes (Humoral Immunity) "Plasma" from produces antibodies Fight off invaders "Memory" cells provide for antibody production later Identify foreign body and become plasma cells → matches up the antibody and divides, makes memory cells, and plasma cells (which actually make antibodies) Antibodies (Y shaped), find a place where they can attach, and stick on the antigen Natural Killer (NK) cells Neither T or B, go after tumor & virus-infected cells Like macrophages; will kill anything foreign (goes after cancer cells) Antibodies (Immunoglobulins) (Antibody binding to an invading antigen) Not all stick to antigen; must match up to marker It might take awhile; has unlimited variation B Cells --> humoral-- activated cell becomes an antibody-producing plasma cell or a B memory cell Memory Cells --> Memory cells contain information about the antigen that stimulated its development and remembers it Plasma Cells -->develop from B lymph. to produce and secrete specific antibodies Antibodies--> specific protein produced in humoral response to bind w/ antigen Plasma cells come from B cells Antigen stimulates Helper T which with the antigen stimulates B cell which becomes mother of clones If the antigen is encountered again by a memory T and memory B cells, then the memory B cell produces plasma cells and antibody at a much higher rate -production of antibodies or immunoglobins -mature in bone marrow and proceed to spleen and lymphoid tissue -primarily against bacteria and viruses that are outside of our body's cells -NK Cells are lymp. distinct from T and B lymphs. --> destroy without any prior exposure, tumor and infected with virus cells
Universal Precautions
steps taken to prevent the spread of disease through blood and other body fluids when providing first aid or health care safety precautions at two levels, recommended to protect health care workers from infections, based on the assumption that all patients and all body fluids are sources of infection provide the basic guidelines by which all blood, body fluids, and wastes are considered infected in any client regardless of the client's apparent condition two levels: one general for all individuals and one specific to known infections at all specific sites in the body, like the intestines
Treponema pallidum
syphilis Spirals (spirochetes)
characteristics of lupus
systemic, redness of skin in butterfly-shaped rash developed on the face caused by deposition of nucleic acid-antibody complexes in the skin Anti-nuclear antibodies Fatigue. Fever. Joint pain, stiffness and swelling. Butterfly-shaped rash on the face that covers the cheeks and bridge of the nose or rashes elsewhere on the body. Skin lesions that appear or worsen with sun exposure (photosensitivity)
Clostridium tetani
tetanus Bacilli-rod-shaped Clostridium tetani (tetanus or "lockjaw") Aka tetany
• acute period
the disease is at its height Acute period → recovery? You have all of the signs or symptoms of what is going on Self-limited (just have to go through it; body will eventually develop immunity and fight it off) Yes = signs subside until total recovery No develops fully the clinical manifestations reach a peak length of acute period depends on virulence of the particular pathogen and host resistance
antigenic shift
the process by which two or more different strains of a virus, or strains of two or more different viruses, combine to form a new subtype having a mixture of the surface antigens of the two or more original strains. Antigenic shift→ goes from birds to pigs to people; big shift Dangerous pandemic -the genetic change that enables a flu strain to jump from one animal species to another, including humans Antigenic shift can be the result of a direct jump from an unknown animal strain to humans or a reassortment of two or more influenza viruses within the same cell. ... Viral reassortment is a more complex form of antigenic shift. It occurs when two viruses simultaneously infect the same animal. Antigenic shift is the process by which two or more different strains of a virus, or strain of two or more different viruses, combine to form a new subtype having a mixture of the surface antigens of the two or more original strains.
exotoxins
toxic substances that bacteria secrete into their environment -Secretions (some bacteria) Exotoxins Usually gram + Neurotoxins (tetanus) Enterotoxins (stimulate vomiting) Secrete a poisons toxin secreted by a bacterium usually produced by a gram + bacteria and diffuse through body fluids. they have a variety of effects (interfering with nerve conduction)--> neurotoxins from tetanus bacillus and enderotoxins which may stimulate vomiting and GI distress stimulate antibody productions and used as toxoids to induce an immune response
cell mediated immunity
type of immunity produced by T cells that attack infected or abnormal body cells -Lymphocytes T-Lymphocytes (Cell-Mediated Immunity) Cytotoxic CD8-positive T- Killer cells -> identify foregin antigen and inject/attack the enzyme (DESTROY WHATEVER IT IS) The remember what they killed → good at virus, fungi, protozoa Helper CD4-positive T-Cell Includes memory T cells in lymph nodes Notify the B lymphocytes (where you get antibodies) -The immune response which include cell-mediated and humoral immunity Work together Cell-mediated immunity T Cells --> WBCs Memory T Cells --> remember antigen and quickly stimulates immune response on reexposure -t lymphocytes arise from stem cells (bone marrow and travel to the thymus) -cell mediated immunity develops when t lymph. with protein receptors on the cell surface recognize antigens on the surface of the target cells and directly destroy the invading antigens -effective against virus-infected cells Tissues to develop immune cells Bone marrow → produces lymphocytes Thymus → T cells ; where you are an infant (body is teaching itself what itself is→ major histocompatibility) ***one marrow→ where lymphocytes are made T lymph → cell mediated immunity ; mature in thymus gland B → humoral immunity (making antibodies); mature in bone marrow -cytotoxic cd8 positive t-killer cells destroy the target cell by binding to the antigen and releasing damaging enzymes -helper cd4 positive t cell facilitates the immune response -memory t cells remains in the lymph nodes for years and ready to activate the response again if the invader returns
Culture and Gram staining
using specific specimens such as sputum in pts in whom tb is suspected blood cultures may be examined to check the distribution or possible spread of infecting agent -kirby-bauer method (disc diffusion method) and the minimum inhibitory concentration -drug therapy is ordered A Gram stain is typically ordered along with a culture when a bacterial or sometimes fungal infection is suspected. It is also usually performed when the result of a culture is positive, on a sample of the bacteria grown in the culture. Test results are reported promptly to help guide treatment