Infectious Disease Intro Flashcards
What is the difference btw Exogenus and Endogenous bacteria?
Exogenuous from exposure
Endogenous from normal flora
What are endogenous bacterial infections secondary to?
Alteration in tissue structure or function
3 examples of Endogenous problems?
1) Perforation (Gram -)
2) Obstruction (Strep pneumoniae)
3) Alteration of host defenses (Candida)
Highest cause of pneumonia?
Strep Pneumoniae
What happens after viral infections?
Bacterial respiratory tract infections with normal flora due to tissue swelling and obstruction
3 examples of organisms not commonly found in mouth, nose and oropharynx?
1) B-hemolytic streptococci
2) Hemophilus influenza (type B)
3) Neisseria meningitidis
Difference between exotoxins and endotoxins?
Exotoxins G+ endotoxins G-
What is the presence of capsules indicative of?
Evasion of innate immune and antiphagocytic processes
What is the incubation time of hepatitis?
2 weeks
Where is Staph aureus normally found?
Skin and mucosal surfaces
Propagation of S. aureus?
Extracellular
What toxin does S. aureus use?
Exotoxin, toxic shock and food poisoning
Immune response of S. aureus?
Neutrophils
Coagulase + or - for S. aureus?
+
Problem with inability to produce immunoglobulin?
Encapsulated organisms
Problem with cellular immunity?
Intracellular organisms like virsues and rickettsia
Problem with neutrophils?
Staph and strep
Problem of phagocytes?
Encapsulated organsisms
Contagion based on what two principles?
Limit exposure and not allowing colonization to move out of areas where they are normally found
When will patients not show typical signs and symptoms?
Patients with altered immune response or vascular insufficiency.
Koch’s postulates? (4)
1) Organism regularly found in lesions of disease
2) Organism can be isolated as single colonies on solid medium
3) Inoculation of culture causes lesions
4) Organism can be recovered from lesions
High virulence means what?
Capable of causing disease in a normal host
Low virulence means what?
Capable of causing disease only in hosts with low resistance or impaired defenses
What type of immune response is phagocytosis?
Non-specific
