Block 9 Week 1 Bacteri Flashcards
Clostridium dificile
Gram positive bacilli which is an obligate anaerobe which forms part of the commensal bacteria in the gut. If levels are increased, causes pseudomembranous colitis with yellow-white plaques, transmitted by foecal-oral contact.
Escherichia Coli
Gram negative anaerobic baccili bacteria which is obligate anaerobe and capsulated. It is part of the gut’s normal commensal bacteria. Transmitted via contaminated food which causes GI symtpoms. Most common cause of UTI and can be transmitted via undercooked hamburger meat, resulting in haemolytic uraemia syndrome.
Salmonella enterica
Gram negative bacilli transmitted by contaminated food. Infilitrates and proliferates in cells by rearranging the cytoskeleton, modifying phagosome maturation pathway. It resides in a vacuole where it replicates until cell lysis, allowing it to evade antibiotics and the immune response.
Listeria monocytogenes
Gram positive bacilli which is transmitted via contamined food, where infection is initiated in the GI tract. It escapes the vacuole and resides in cyptoplasm, causing intestinal illness
Vibrio cholarae
Gram negative bacilli transmitted via water which is extracellular and releases the exotoxin cholera.
Increases intracellular cAMP levels to affect nA+/cL- exchanger, leading to loss of fluid and electrolytes through diarrhoea which must be replaced through fluid replacement.
Streptococcus pyogenes
Gram positive extracellular bacteria producing pathogen which produces beta haemeloysis to cause complete breakdown of haemoglobin and considered B-haemolysin. Commonly found in the skin and throat and can cause impetigo (skin infection) or pharyngitis/strep throat and cellulitis.
Clostridium botulinum
Gram positive bacilli which forms spores containing the neurotoxin botulinum which blocks acetylcholine release and causes flaccid paralysis and respiratory arrest. → honey
Neisseria meningitidis
Gram negative cocci bacteria which causes meningitis and is enveloped so requires a medium for transport
Pseudomonas aeurginosa
Gram negative bacilli which is a major cause of
Nosocomial Pneumonia in immunocompromised individuals
Otitis externa
What is haemolytic uraemia syndrome?
Caused by shiga toxin from E.Coli bacteria which results in thrombosis of small blood vessels in the kidney. This results in acute kidney injury, disrupting EPO and TPO production causing haemolytic anaemia and thrombocytopenia.
What is staphylococcus aureus?
Gram positive cocci which is beta-haemolytic and completely breaks down RBCs. The most common cause of septic arthritis, cellulitis and osteomyelitis. It resides on the skin and causes skin infections and acute endocarditis, common in IV drug users.
Typically treated with vancomycin.*
What is staphylococcus epididermis?
Gram positive cocci which produces a biofilm extracellular material that typically causes infection in insertion of catheters and prosthetic joints. It is the most common cause of endocarditis
What is staphylococcus saprophyticus?
Gram positive cocci which commonly causes UTI infections in young sexually active women.
What is MRSA?
Mutation of staphylococcus aureus of the penicillin binding protein to become methicillin resistant and is a nosocomial infection. It typically appears as a sin infection with swelling, redness and pus formation. Other symptoms include chest pain, chills and headache
What is a side effect of vancomycin use?
Glycopeptide antibiotic which inhibits incorporation of subunits into the peptidoglycan matrix of bacteria cell wall. Causes red man syndrome, where there is a erythematous ash on the upper body, with angioedema and hypotension possibly occurring.
