Streptococcus Pneumoniae 2 Flashcards
Protein virulence determinant in S pneumoniae
Streptococcus pneumolysin
Shape of S pneumoniae
Lancelate, diplococcal
Optochin
Antimicrobial
Quinine derivative
Sulphonamide
Useful anti microbial against S pneumoniae
S pneumoniae developed resistance in 1943
Sulphopuridine
Anti microbial against S pneumoniae
S pneumoniae developed resistance in 1938
Type of penicillin useful against S pneumoniae
Penicillin G
Partial resistance observed in 1941
What is lobe filled with in lobar pneumonia?
Fluid, macrophages, neutrophils, pus
Patterns of S pneumoniae resistance
3/4 of resistant strains only have intermediate resistance
Can be treated if in a site where penicillin can be administered
Type of resistance conferred by beta-lactamase
All or nothing (bacteria either degrade penicillin or they don’t)
Penicillin binding proteins
Transpeptidase
Type of resistance conferred by mutations in penicillin binding proteins
Continuous
Degree of resistance depends on number of mutations to penicillin binding proteins
Ways to measure antibiotic resistance
1) Minimum inhibitory concentration test
2) Disc susceptibility test
Ways to measure antibiotic resistance
1)
2)
1) Minimum inhibitory concentration test
2) Disc susceptibility test
Minimum inhibitory concentration test 1) 2) 3) 4)
1) Dilutions of antibiotic are made
2) Standard number of bacteria are added
3) Incubated overnight4)
The lowest dilution of antibiotic that inhibits growth minimum inhibitory concentration
Disc diffusion test
1)
2)
3)
1) A standard number of bacteria are cultured on an agar plate
2) Discs impregnated with relevant antibiotics are added to agar
3) After overnight incubation, clearance zone diameters are measured
