Microbiology Flashcards
Strep sanguinis =
Strep viridans
Action of chloramphenicol
Acts on the cell wall = bactericidal
What is an endotoxin?
What is the immune response?
Feature of bacterial cell wall
e.g. lipopolysaccharide
- Freed when the bacteria is lysed/killed = activates coagulation and complement
e.g. E coli > haemolytic uraemic syndrome
Which bacteria have endotoxins?
Usually gram -VE
Two examples of exotoxins
Which bacteria mainly produce exotoxins
- Botulinum - toxin blocks ACh release
- Cholera - increases levels of adenylate cyclase to cause hypersecretion of chloride ions/water
Gram +VE
Antibiotics with actions on the cell wall (4)
Penicillins
Carbopenems
Glycopeptides e.g. vancomycin
Cephalosporins
Antibiotics with actions on DNA synthesis (3)
Metronidazole
Sulphonamides e.g trimethoprim
Fluoroquines e.g. ciprofloxacin
Antibiotic that acts on RNA synthesis
Rifampicin
Antibiotics that act on protein synthesis (3)
Aminoglycosides e.g. gentamicin 30S
Macrolides e.g. erythromycin, clindamycin 50S
Tetracyclines - 30S
Protein subunit - makes a macrolide sandwich (50S)
Antibiotics that act on 50S subunit
Macrolides
e.g. erythromycin, clarithromycin
Antibiotics that act on 30S subunit
Aminoglycosides e.g. gentamicin
Tetracyclines e.g. doxycycline
When should live vaccines be avoided? (3)
Immunosuppressed
Malignancy e.g. leukaemia, lymphoma
Pregnancy
Live Attenuated Vaccines (6)
BCG
MMR
Typhoid
Yellow fever
Polio
Rotavirus
Inactive Vaccines (2)
- Problem
Rabies
Hepatitis A
- need boosting, not as immunogenic
Influenza vaccination
Nasal = ALIVE (alive attenuated)
IM = UNALIVE (inactive)
Toxin Vaccines (3)
- Problem
Diptheria
Pertussis
Tetanus
needs boosting, not as immunogenic
Conjugate Vaccines (3)
- How do they work?
Pneumococcus
Haemophilus
Meningitis
Make lipopolysaccharide more immunogenic
Toxic Shock Syndrome
- bacteria
- mechanism
= staph aureus
Occurs due to the release of enterotoxins causing massive inflammatory response
enterotoxin = exotoxin
B-haemolysis
- bacteria that show
= complete haemolysis
Group A and B streptococcus
A-haemolysis
- bacteria that show
= partial haemolysis
Strep viridans, strep pneumoniae
What does Group A strep produce?
Haemolytic exotoxins e.g. streptokinase
Is clostridium sp gram positive or negative?
Positive - anaerobic
What does E.coli 0157 produce?
shigella like toxin = endotoxin
= into circulation results in TTP and HUS
Lymphogranuloma venereum
L1-L3 serotype of chlamydia trachomatis
L1-L3 serotype c. trachomatis
- Presentation
Lymphogranuloma venereum
= lymphadenopathy, proctitis, ulceration
Process of viral replication (6)
Free virus
Attachment to host cell
Penetration of cell
Uncoating of virus
Synthesis of viral DNA or RNA
Assembly and release of virus
Zidovudine =
AZT
Nucleoside reverse transcriptase inhibitor
Classes of drugs used in HIV (3)
NRTI
Non-NRTI
Protease inhibitors
Progressive Multifocal Leukoencephalopathy
- virus
- associated conditions
JC virus
- HIV and MS when using immunosuppression
JC Virus
PML
EBV associations
Burkitt’s lymphoma
Hodgkin’s lymphoma
HTLV-1 association
T cell leukaemia
False negative result in syphillis (4)
SLE
Anti-phospholipid
Pregnancy
HIV
Results in ACTIVE syphillis infection
Positive VDRL
Positive treponomal test
Results in TREATED syphillis infection
Negative VDRL
Positive treponomal test
Testing for viral protein
Western blotting
ProTEST = west
Management of Campylobacter in severe infection
ClarithromycinM
Management of toxic shock syndrome
Penicillin + clindamycin
