Microbiology Flashcards
Name 3 gram positive cocci:
Staphylococcus, streptococcus, enterococcus
Name 4 gram positive bacilli:
Listeria, clostridium, bacillus, corynebacterium
Name a gram negative cocci:
Neisseria
Name 5 gram negative bacilli:
E. coli, Klebsiella, salmonella, pseudomonas, bacteroides.
Which drugs inhibit cell wall synthesis?
Beta-lactams: penicillins, cephalosporins, carbapenems.
Glycopeptides: vancomycin, teicoplanin
Which drugs inhibit protein synthesis?
Amino glycosides: gentamicin, tobramycin Tetracyclines: doxycycline Lincosamides: clindamycin Macrolides: azithromycin Fusidic acid Linezolid
Which drugs are inhibitors of nucleic acid synthesis?
Folic acid synthesis inhibitor: trimethoprim, sulphonamides.
Fluroquinolones: ciprofloxacin
Rifampicin
Metronidazole
Name 3 agents which cause atypical pneumonia?
Legionella haemophilia, Coxiella burnetii (Q fever),
Mycoplasma
How can you differentiate typical and atypical pneumonia?
Atypical pneumonia: typically sick with non resp symptoms for longer. ~ 4 days of malaise and fevers before cough and SOB etc.
What gram stain is a more likely result for hospital acquired pneumonia?
Gram -
What is the commonest cause of typical pneumonia?
Strep. Pneumoniae
In which people is it difficult to differentiate between typical and atypical pneumonia?
V. Young and v. Old
What are 4 narrow spectrum penicillins?
Penicillin G - benzylpenicillin
Penicillin V - phenoxymethylpenicillin (available orally)
Procain penicillin
Benzathine penicillin (IM)
Name 2 moderate spectrum penicillins
Amoxicillin and ampicillin
Name 2 broad spectrum penicillins, when you would give them, and how.
Piperacillin and ticarcillin.
Give if px is very sick or pseudomonas aeruginosa infection is suspected. Often combined with beta lactamases.
IV
Name 2 organisms that produce beta-lactamases and 2 beta lactamase inhibitors.
Staph aureus and Klebsiella.
Tazobactam and clavulanic acid.
What is augmentin?
Amoxycillin- clavulanate
If you have EBV, you’re on penicillin, and you develop a rash, is it definitely an allergic reaction to penicillin?
No
If a px becomes anaphylactic to penicillin, what drugs should you use instead?
Cephtriaxone, fluroquinolone
Which group of bacteria are intrinsically resistant to cephalosporins?
Enterococci
Which antibiotics have intracellular activity and when are they used?
Tetracyclines - doxycycline.
Macrolides - azithromycin
Fluroquinolones - ciprofloxacin
Used against strep. pneumoniae, atypical pneumonia or in case of allergies.
Which antibiotics are anti-staphylococcal penicillins?
Flucloxycillin, methicillin, dicloxacillin
Anti-staphylococcal cephalosporins?
Cephazolin IV/IM
Cephalothin IV/IM
Cephalexin PO
What is the incubation fever of typhoid fever?
2-3 weeks
Which antibiotics have gram -ve activity?
- Beta lactams: moderate spectrum penicillins - Amoxycillin, 1st and 2nd generation cephalosporins - cephazolin.
- Penicillin/beta lactamase combinations.
- 3rd and 4th gen cephalosporins
- Gentamycin
- Fluroquinolones
What is metronidazole used for?
Anaerobes
What do you prescribe if enterococcus infection is suspected?
Ampicilin
If someone develops diarrhoea, abdominal pain and fever after antibiotic treatment, what should you suspect?
Clostridium Difficile
Why should you not prescribe Aminoglycosides unless really necessary?
Risk of reversible tubular damage to kidneys and irreversible inner ear damage.
When should you treat asymptomatic bacteruria?
When px is pregnant or undergoing urological procedure.
Where does staph aureus love to infect?
Bones, especially the back.
When do you give vancomycin orally?
For clostridium difficile infection. It isn’t absorbed and goes straight to the gut.
What are recurrent rigors commonly caused by?
Bacterial infection
What could be a cause of severe muscle pain, even without fever?
Sepsis
What is fever in the elderly rarely caused by?
Viruses
Sepsis in the elderly man may not present with…
Fever- the older the colder
What is a medical emergency worse than a septic px with fever?
One with hypothermia
If a px has fever post-operatively, what is the most likely cause?
The surgery
What symptoms are rarely displayed in viral hepatitis?
Jaundice in a febrile px.
Generalised rashes that also include the hands and the feet are likely to be caused by…
Viral infection, drugs, rickettsial infections or Syphilus.
What disease needs to be excluded from a febrile patient returning from SE Asia or Africa?
Malaria
Staph aureus in the urine is a sign of what, until proven otherwise?
Staphylococcal bacteremia
What should you think of in a px complaining of acute sore throat, trouble swallowing and/or hoarse voice?
Acute Bacterial epiglottitis
What should you think of in a febrile px with back pain?
Vertebral osteomyelitis and epidural abscess.
How do you confirm viral meningitis?
PCR
