Can only replicate using host- immediate or dormant (herpes) fungi Large; live on body as normal flora, single celled, thick cell wall, do not have peptidoglycan, contain nuclear membrane, ER, mitochondria, secretory apparatus Mycotoxicosis-dx caused by ingestion of fungal toxins Amanita mushroom-hepatotoxin- liver failure, tx: transplant/dialysis Aspergillus flavus-aflatoxins- hepatotoxic/tumor causing; in spoiled grain or peanuts Resist PCN and cephalosporin Mycosis related dx usually mild unless cause opportunisitic infection Tineas-scalp (capitis), feet (pedis) groin/jock itch (cruris) hair, skin, nails- dermatophytes Main groups-yeast and molds Candida-yeast, reproduce by budding Molds-reproduce by hyphae- long hollow branching filaments Strep/staph Cocci-round spherical
Chain-strep Cluster-staph E. Coli Bacilli-rod Syphilis Spirochets-helical Mycoplasm a pneumoniae Pleomorphic-no shape Clostridium Spore forming, Become dormant and impervious to host defenses Rickettsia Rod, spherical or pleomorphic Spread by insects ex: ticks Taxonomy Species based of similar broad features ie: staphylococcal Gram - Thin walls prevent retention of stain Extra membrane more resistant to abx Ex: gonorrhea, meningitis, salmonella, shigella, klebsiella Endotoxins released when lysed-fever low bp, DIC, septic shock Gram + Retain purple gram stain, release exotoxins (type I, type II, type III) Ex: staph, strep, bacillus (anthrax) and clostridium (tetanus) Secrete teichoic acid-protect against complement mediated lysis Type 1- stimulate over production of proinflammatory cytokines ie: food poisoning staph aureus, toxic shock syndrome staph aureus, scarlet fever strep pyogenes Type 2- damage cell membrane, ie: strep, penumoniae, some e. coli, c. perfringes which cause gangrene Type 3- enter cell, cause damage ie: clostridium and shigella Acid fast bacilli Thick walls composed of lipids, slow growth, abx must be given for months or years Cultures take 8 weeks Ex: TB, Leprosy, M. Avium Aerobic Myst have o2 to live Pseudomonas gram- aerobic bacillus: chronic resp dx found in soil/water Gram +: anthrax, food poisoning (rice) Anerobic Cant grow with o2 Bacteroides-sepsis, peritonitis, abscesses, bacteriodes fragilis most common-colon, vagina- normal flora ie: clostridium gram+ rod
tetanus-spastic paralysis-lock jaw (soil), botulism-blocks release of acetylcholine- descedning paralysis (soil, improper canning), c.diff- pseudomembranous colitis- Faculatative anerobes can grow in either ie: e coli k. Identify the clinical manifestations associated with infectious diseases. l. Differentiate between exogenous and endogenous pyrogens. Endogenous- arising from break in mucosa, not communicable Exogenous- m. Examine the pathological effects and properties of streptococci, staphylococcal, VRE, E coli, and candida infections. Streptococci-gram positive Group A beta-hemolytic (strep pyogenes)- fevers, strep throat, scarlet fever, rheumatic fever, post strep glomerulonephritis; capsules have hyaluronic acid-resist phagocytosis strep o protein destroys rbcs and wbcs, develop antibodies-aso titer used to dx infection, streptokinase-dissolves clots so bacteria excapes; exotoxins released; A-streptococcal toxic shock
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- Fall '15