deck 5 Flashcards
How many people will never get TSST-1 antibodies?
20%
What bacteria does yellow pus/discharge suggest?
staph aureus
What drug would you give in anticipation of either staph aureus TSS or Group A strep TSS?
vancomycin, clindamycin, and rifampin.[rifampin= mucous membrane penetration. clindamycin= stops toxin production. Vanco=strong Ab.]
What is a left shift in WBC
immature WBC meaning an infection
What are the 5 criteria for staph TSS?
- Body temp >1022. Systolic BP<903. Diffuse rash/erythroderma4. Desquamation upon recovery5. Involvement of 3 or more organs
What is clindamycin used for?
protein synthesis inhibitor that has the capacity to inhibit exotoxin production at concentrations below its antimicrobial concentration
What does staph aureus need for TSST-1 production?
oxygen [tampons]
Does strep TSS need oxygen for production of TSST-1?
No they aerotolerant anaerobes but never use oxygen
What phase of bacterial growth is defined as enzymes being induced to allow bacterial growth?
Lag phase
What phase of bacterial growth is defined by doubling times?
log phase
What happens in post-exponential phase of bacterial growth?
toxin–small molecules signal a quorum and induces exotoxin production
What bacterial phase is defined as nutrients used up an growth stops?
stationary phase
What type of bacteria die quickly in death phase?
obligate fermenters [acid, superoxide, H2O2 build up]
What enzymes must obligate aerobes have?
superoxide dismutase SODcatalase
What enzymes must a facultative anaerobe (aerobe) have?
SODcatalase
What enzymes do aerotolerant anaerobes have?
SOD, but no catalase
What types of bacteria neither have SOD nor catalase?
obligate anaerobes
What type of bacteria are Bacillus and Mycobacterium?
obligate aerobes
What type of bacteria is Staph and Escherichia?
Facultative anaerobe
What type of bacteria are streptococcus?
aerotolerant anaerobes
What is a microaerophiles?
prefer reduced amounts of oxygen [Neisseria and Borrelia]
What is Gram+, Catalase+, coagulase+?
S. aureus
What groups of bacteria are catalase negative, cocci and gram positive?
streptococci and enterococci
What is gram positive, cocci, catalase negative, B hemolysis and bacitacin sensitive?
Group A strep
What is Gram positive, cocci, catalase negative, a hemolysis, and optochin sensitive?
streptococcus pneumoniae
What type of bacteria is a peptostreptococcus?
obligate anaerobe
anaerobe or aerobe Gram +Rod–listeria?
aerobe
anaerobe or aerobe Gram +Rod–lactobacillus?
aerotolerant anaerobe
anaerobe or aerobe Gram +Rod–bifidobacterium?
anaerobe
What are the 2 spore formers?
Bacillus [aerobe]Clostridium [anaerobes]
What bacteria category do neisseria and acinetobacter fall under?
Gram negative cocci
What bacteria category does enterobacteriaceae, pseudomonadaceae, fusobacterium, haemophilus, bordetella, legionella?
Gram neg. Rods
What are the 2 main lactose negative bacteria?
salmonella and shigella
What agar do we use primarily for lactose tests?
MacConkey- pink = lactose positivewhite=lactose negative
How is the MacConkey agar selective?
inhibits gram positive growth
What is a mesophile?
survive at body temperature
Why do we have fevers?
most bacteria require more iron at higher temperatures–this is why too much Iron is bad
How do bacteria scavenge iron?
siderophores
What antibiotics target DNA gyrase?
quinolones
Where does bacterial transcription terminate? What might it require?
hairpin turn, may require rho factor
What antibiotic is used to inhibit the initiation of transcription? What is its strong quality?
Rifampin [ also rifamycin]High mucosal surface penetrator [red urine and red contacts]
What does bacterial translation require?
Shine Dalgarnoinitiation factors30S and 50S subunits for 70Sribosomes
What are the 3 protein synthesis inhibitors of 50S ribosome?
chloramphenicolerythromycinclindamycin
What 50S inhibitor penetrates the CNS well?
chloramphenicol
What 50S inhibitor is used in penicillin allergic patients?
erythromycin
What 50 S inhibitor may allow the growth of Clostridium difficult and lead to pseudomembranous enterocolitis?
clindamycin
What are the major areas of toxicity for 30S inhibitors?
oto and nephro
How do amino glycoside protein synthesis inhibitors work?
cause the wrong amino acyl tRNA to bind and at higher concentration binds ribosomes and causes them to fall off[perfect for gram-]
The 30S inhibitor tetracycline may cause what side effects?
upset stomachimpairment of bone development under 12stains teeth dark of infants whose mothers took it during preg. [BINDS CALCIUM!]
What is mupirocin used for? how does it work?
topically in treating impetigo due to strep/staphinhibits isoleucine tRNA
What is polymyxin B used for?
membrane activity–used in affinity columns to remove LPS from cloned proteins[binds tightly with Lipid A]
What does daptomycin cause?
membrane disruption
How do sulfonamides and trimethoprim work? which one is specific to bacteria over human cells?
-blocks sequential steps in folic acid metabolism-sulfonamide is specific for only bacteria, but trimethoprim is 50k-100k more active on bacteria that human cells
What types of bacteria are resistant to sulfonamides and trimethoprim?
anaerobes are resistants[kills aerobes, facultative bacteria and pneumocystis carinii (fungi!!!!)]
What is the difference between minimum inhibitory concentration and minimum bactericidal concentration?
inhibitory is the amount of agent needed to impede visible growthbactericidal is the amount needed to kill the organism by 3log
Is tetracycline bactericidal?
no, bacteriostatic
anaerobe or aerobe Gram +Rod–corynebacterium?
aerobe
anaerobe or aerobe Gram +Rod– propionibacterium?
anaerobe
