Flashcards in Microbiology Deck (260)
How do antibiotics cause diarrhea?
increased risk of infection from PPI acid suppression
Treatment of antibiotic associated diarrhea caused by C.diff?
stop the antibiotics, oral vancomycin or metronidazole, isolationg
Antibiotics for ruptured appendicitis?
CoAmoxiclav or cefuroxime and metronidazole
What is the purpose of an Mz disc?
it contains metronidazole which confirms the presence of anaerobic bacteria if it prevents growth
Antibiotics for anaerobic bacterioides?
Antibiotics for ascending cholangitis?
What is dysentery?
inflammatory disorder of GI tract with blood and pus in the faeces with pain, fever, abdominal cramps, usually caused from disease of the large intestine
Gram negative bacilli organisms in the GI tract?
salmonella, shigella, e.coli, campylobacter jejuni, helicobacter pylori
What is infectivity?
the ability to become established in a host
What is virulence?
the ability to cause disease
What is invasiveness?
capacity to penetrate mucosal surface to reach normally sterile sites
What is a microbiome?
the totality of microorganisms, gentic elements and enviromental interactions
the use of genetics to describe microoragnisms diversity
What are the different types of adhesions that help bacteria bind to mucosal surfaces?
fimbriae, non fimbrial proteins, lipid, glycosaminoglycans, lectins of viruses and parasites, miscellaneous viral capsids
Virulent factors in bacteria?
pili for adherance to mucosal surface
motility to reach mucosal surfaces
IgA protease for IgA cleavage
iron binding proteins to trap iron
capsule to prevent phagocytosis and complement deposition
antigenic variation for evasion of antibodies
Types of toxins?
ADP ribosylating, adenylate cyclase, RNA gangliosidase, metalloproteiniase, cholesterol dependent
What are superantigens?
bacteria and viruses can produce antigens that bind outside the peptide groove of the T cell receptor to stimulate a large number of T cells e.g. EBV
Where are the 2 places that toxins can be?
chromosomal or on plasmids
What is C.diphtheriae?
a toxin spread by droples that inhibits protein synthesis and toxin recognition on Elek plate, preventing with vaccination