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Gram Positive Bacillus. Medically Important GPR. Bacillus Clostridium Listeria Erysipelothrix Lactobacillus Actinobacteria Streptomyces Proprionibacterineae Corynebacterium Nocardia Mycobacterium. Bacillus anthracis. Characterisitics GPR FA Capsule Spore: central endospore
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Medically Important GPR • Bacillus • Clostridium • Listeria • Erysipelothrix • Lactobacillus • Actinobacteria • Streptomyces • Proprionibacterineae • Corynebacterium • Nocardia • Mycobacterium
Bacillus anthracis • Characterisitics • GPR • FA • Capsule • Spore: central endospore • Nonmotile • Reservoir, zoonotic • Hoof stock (sheep, cattle, goats) • Fur, hides (textile workers) • Soil contaminated with spores • Virulence • Capsule • Spore • Exotoxin (anthrax toxin) • Necrosis • Edema • Protective Ag
B. anthracis diseases • Exposure • Inhalation • Inoculation • Ingestion meat • Dz • Gastrointestinal • Hemmorhage/death • Cutaneous • Eschar/toxemia • Inhalation • Toxemia/death
B. anthracis Cutaneous Anthrax: Eschar
B. anthracis • Dx • Culture/Isolation • Tx • AB (cipro) • Prevention • Vaccination (toxoid) • Proper disposal • Chemical disinfection • Burn carcasses
B. cereus • Characteristics • Aerobic • Non-encapsulated • Motile • spore • Virulence • Spores • Enterotoxins • Hemolysins • Lecithinase (pLC) • Dz • Food poisoning • Catheter sepsis • Ocular infections
B. subtilis • Location • Soil • Decaying organic matter • Nonpathogenic • Research organism • Endospores • antibiotics • Commercial use • Enzyme production • Insect toxin • Fungicide • Food spoilage
Clostridium • Examples • C. tetani • C. perfringes • C. botulinum • Characteristics • GPR • Obligate anaerobes • Motile • Spore former (terminal) • Exotoxins
C. perfringens • Membrane disrupting toxin (phospholipids) • Alpha toxin (lecithinase) • Rupture RBCs • Destroy Tissue • Enzymes • Collagenase • Hyaluronidase • DNase • CH2O fermentation Gas • Exposure • Puncture wounds, fractures • Surgical • Contaminated food • Diseases • Food poisoning • Improper cooking • V/D • Gas gangrene • Anaerobic cellulitis • myonecrosis
Gas Gangrene Treatment Debride AB Hyperbaric O2
C. tetani • Epidemiology: saphrophyte • Soil • Dust • GI tract • Wounds (deep) • Burns • Umbilical stump • Animal bites • A-B neurotoxin (exotoxin) • Tetanospasm • Blocks release of inhibitory NT • Glycine • Relaxes opposing muscle • Without: both muscle groups contract • Tonic Spasms • Localized (Lockjaw) • Cephalic • Generalized • Death respiratory failure
C. tetani • Dx • Spores in wound • Blood toxin levels • Toxin neutralization test • Treatment • Antitoxin (HTIg) • AB • Debride • Curare poison • paralysis • ventilator • Prevention • Vaccination • Toxoid (DPT) • Antitoxin
Tetanus neonatorum • C. tetani • Umbilical cord infected • soil, dirt rubbed on stump • Dirty instruments
C. botulinum • Location • Soil • Water • Improper canning • GI tracts of animals • Epidemiology • Intoxication • Food borne • Toxin (canned food) • Infant • Ingestion of endospores • Source: honey • Wound • endospores
C. botulinum • Pathogenicity • A-B neurotoxin • botulinum toxin • 7 toxins A-G • Type A • Proteolytic • Heat resistant • Type B: both • Type E • Nonproteolytic • Heat labile • Bind to neuron • prevent ACH from binding at NMJ • Flaccid paralysis • Descending • Death in 3-7 days
C. botulinum • Dx • Culture/Isolation • Symptoms • Tx • Antitoxin • AB: penicillin • Ventilator • Prevention • Proper food handling • Boiling 10 minutes
Clostridium difficile • GI source • Epidemiology • Long term care facilities • Chronic AB use • Fecal-oral route • Pathogenicity • Toxins • Spores • Diseases • Colitis pseudomembrane • Cecal perforation = fatal
Actinobacteria • Suborder Actinomycinae • Suborder Propionibacterineae • Suborder Streptomycineae • Suborder Corynebacterineae • Family Corynebacteriaceae • Family Mycobacteriaceae • Family Norcariaceae
Actinomycosis • Actinomycetes • Characteristics • Anaerobic • Diseases • Abscesses • Sulfur granules • Body cavities • Jaw • Thoracic • Abd/pelvic
Proprionibacterineae • GPR • Non motile, NSF • FA to aerotolerant • Catalase (+) • Location • Skin • GI • Dairy (cheese) • Types • P. acnes • Body odor • Acne • Oil glands • Acne vulgaris
Streptomycineae • Streptomyces • Aerial hyphae, conidia • Obligate aerobes • Location:soil • Problems • S.C infection • Abscess • Bone destruction • Use • AB synthesis
Mycobacteriaceae • Examples • M. tuberculosis • M. leprae • Characteristics • AF (mycolic acid) • Aerobic • Nonmotile, NSF • Reservoir = humans • Transmission • Respiratory droplets
M. tuberculosis • Slow growing • TB • Pulmonary • Nodular scars • Calcification • T cells and macrophages CT • Tubercle • Caseous necrosis • Disseminated (consumption) • Brain • Bone • Kidneys • GI • LN • Skin • Disease stages • Primary • Latent • Recrudescent
M. tuberculosis • Virulence factors • Mycolic acid • Decrease phagocytosis • Catalase • Mycobactin • Chelates iron • Dx • Culture/isolation of sputum • Radiography of chest • TB skin test (PPD) • Tx • multi-drug • Resistance • Research: rDNA vaccine
M. Leprae (Hansen’s bacillus) • Slow growing • Epidemiology • Tropical environments (TX) • Not readily communicated • Types • Tuberculoid • Rash with plaques • Nerve damage • Lepramatous (Leproid) • Erythemia nodosum • Neuritis • Ulceration/bacteremia • Skin appendage loss Treatment: AB
Corynebacterium • C. diptheriae • Characteristics • Club shaped • Weakly AF • Metachromic granules • Epidemiology • Source: carriers • Cutaneous • Fomites • Respiratory infection • Aerosol • Pharynx, LN, tonsils • Pseudomembrane • Pathogenicity • Diptheria toxin • A-B exotoxin • A: Inactivates proteins • B: attacks heart, NS • Neuraminidase • Protease (Dipthin) coryne = club shaped
C. diptheria disease • Pseudomembrane • Pharynx and tonsils • MM • Nasal • Larynx • External ear (OM) • Conjunctiva • Vulvo-vaginal • Complications (toxins) • Edema • Myocarditis • Neuritis • Cutaneous rash
C. diphtheria • Dx • Pseudomembrane • Metachromic granules • Tx • Antitoxin • AB • Prevention • Vaccination (DPT)
Nocardia • N. asteroids • Characteristics • Saprophyte (soil) • Filamentous, branch • Weakly AF • Transmission • immunosuppressed • Dz • Resp: resemble TB • Skin: abscesses • Tx: AB
Lactobacillales (Lactobacillus) • Characteristics • Coccobacillus • FA – microaerophilic • Lactic acid fermentation • Epidemiology • Food: meat, dairy, fruit • Environment: water • Uses • Food production • Fermented vegetables • Beverages: beer, wine, juices • Milk products: yogurt, cheese • Problems • Food spoilage
Listeria • L. monocytogenes • Characteristics • Soil, mammal gut • Non caspule, NSF • Motile [petrichous flagella] • FA • Catalase (+) • Resist: Cold, pH, temp, salt, bile • Transmission • Direct: neonate, uterus • Vertical • Dz • Food poisoning (dairy) • Skin-> bacteremia-> endocarditis->NS • Tx: AB • Prevention • Cook foods • Pasteurize dairy products
Erysipelothrix • E. rhusiopathiae • Characteristics • Saphrophyte • Nonmotile, NSF • microaerophilic • Epidemiology • Water, sewage • Animals • Pathogenicity: capsule • Transmission: Fecal • Disease • Macropapular rash • Endocarditis • Septicemia • Tx • AB • Animal vaccination (pigs)
Mycoplasmas • Characteristics • Lack cell walls • Pleomorphic (fried egg) • NM • FA-Obligate anaerobes • Examples • M. genitalium • M. pneumoniae • M. hominis • Diseases • Pneumonia • Uritogenital infections