MIDTERMS

• Staphylococci spp.


  Grow in aerobic or microaerophilic conditions
• Pathology


  Study of disease
• Staphylococcus aureus


  Forms golden colonies in mannitol salt agar, transmitted through direct contact and fomites, may lead to the formation of pimples
• Pathogenesis


  Studies how disease develops
• Major Toxins of Staphylococcus aureus

  • Toxic Shock Syndrome Toxin 1
  • Panton-Valentine Leukocidin Toxin
  • Hemolysin
  • Exfoliatin
  • Enterotoxin
• Etiology


  Cause of disease
• Toxic Shock Syndrome Toxin 1

  Produced at the site of infection and can enter the bloodstream, growth in vagina/surgical sites
• Infection


  Invasion of the body by pathogenic organisms
• Panton-Valentine Leukocidin Toxin


  Pore forming toxin that affects leukocytes and results in the release of inflammatory mediators
• Disease


  Infection results in a change from a state of health
• Carrier


  Person or animal with asymptomatic infection that can be transmitted to another susceptible person or animal
• Hemolysin


  Affects erythrocytes to release Fe2+ in the blood
• Normal Microbiota


  Microbial populations that rapidly establish themselves in the newborn's body after birth
• Pathogenicity


  Ability of an infectious agent to cause disease
• Exfoliatin


  Causes Bullous impetigo which could lead to Staphylococcal Scalded Skin Syndrome, usually presents 48 hours after birth
• Cutaenous anthrax


  Black eschar
• Resident Microbiota


  Microbes that remain throughout one's life
• Virulence


  Quantitative ability of an agent to cause disease (involves adherence, persistence, invasion, and toxigenicity)
• Enterotoxin


  Lands on food, heat stable, and can cause food poisoning
• Transient Microbiota


  Microbes present for a certain time then disappear
• Adherence


  • Major initial step in the infection process where bacteria stick to the surfaces of host cells
• Treatment for Staphylococcus aureus infections

  Topical antibiotics and drainage for abscess and other closed suppurating lesions
• Synergism


  Two microbes acting together
• Invasion


  • Bacteria, animal parasites, fungi, and viruses enter host cells or tissues and spread in the body
• Inhalational anthrax


  Wool sortersdse
• Methicillin Resistant S. aureus infections


  High usage of antibiotics or rampant antibiotic use in factory farms
• Etiology of Infectious Diseases

  1. Attachment of bacteria to host cells

  2. Bacteria quickly multiply and spread through tissues

  3. Bacteremia then ensues
• Microbiota


  Microbial flora harbored by normal, healthy individuals
• Gastrointestinal anthrax


  Rarest, formation of ulcers
• Prosthetic-Related infections


  Direct intraoperative contamination or hematogenous spread
• Pathogen


  Microorganism capable of causing disease
• Symptoms


  Subjective feelings
• Staphylococcus epidermidis


  Most dominant bacteria on the human skin, part of normal flora, common contaminant of blood cultures, and is made up of exopolysaccharides
• Injection anthrax


  Small outbreak due to heroin addicts
• Nonpathogen


  Microorganism that does not cause disease and may be part of the normal microbiota
• Signs


  Objective changes that can be measured
• Staphylococcus saprophyticus


  Makes urinary pH neutral or alkaline by hydrolyzing urea into carbon dioxide and ammonia through urease
• Opportunistic Pathogen


  Capable of causing disease only when the host's resistance is impaired
• Blood Brain Barrier (BBB)


  Semipermeable membrane that protects the brain from the environment
• Principal Microorganisms

  • G(-) bacteria