My final revision slides for microbiology in 2nd clinical year pathology finals at the University of Cambridge.

1. Antibiotics – The barest facts
Penicillins – gram +ve bacilli/cocci and gram –ve cocci (proliferating bacteria)
- Flucloxacillin – b-lactamase resistant
- Amoxicillin – H. influenzae
- Augmentin (Co-amoxiclav = Amoxicillin and Clavulanate) – b-lactamase resistant, gram –ve bacilli
- Tazocin (Piperacillin and Tazobactam) – b-lactamase resistant, Pseudomonas
Cephalosporins – broad spectrum
- Ceftazidime – Pseudomonas
Carbapenems – exceptionally broad spectrum
- Meropenem – EXCEPT MRSA, VRE, Mycob.. Mycopl., Chlam., Ricketts., Klebs.
Macrolides – gram +ve bacilli/cocci and gram –ve cocci (similar to penicillins)
- Clarithromycin – + Myocbacteria (not TB), Mycoplasma, Chlamydia, some gram -ve
Lincosamines – narrow spectrum, gram +ve cocci incl. MRSA (?) and anaerobes
- Clindamycin
Sulfonamides – broad spectrum
- Trimethoprim – H. influenza, E. coli, Klebsiella
Tetracyclines – broad spectrum
- Doxycycline – Chlamydia, Rickettsia, Brucella, Borrelia
Glycopeptides – narrow spectrum, gram +ve cocci
- Vancomycin – MRSA
Aminoglycosides – gram –ves unless synergism with other antibiotic
- Gentamycin
Imidazoles – as a class of compounds they are antifungals
- Metronidazole – anaerobes, C. diff!
Quinolones – broad spectrum
- Ciprofloxacin – only oral AB against Pseudomonas, Chlamydia, E.coli, Klebsiella
ATYPICALS GRAM –ve BACILLI AND BACTERIA OF THE GUT

2. Treating Infectious Diseases – The barest facts
UTI – E. coli, Klebsiella, Enterococci = Gram –ve bacilli
- Trimethoprim (better if resistance likely)
- Co-Amoxiclav
- Ciprofloxacin possible but likelihood of C. diff
- If ESBL (Extended spectrum b-lactamase)
o Meropenem – hospital
o Nitrophenytoin – community
Pneumonia – COMMUNITY: 90% Strep. pneumoniae, Haemophilus influenzae, atypical – HOSPITAL: MRSA, gram –ve
- COMMUNITY
o Severity determined by CURB65
o Low: Amoxicillin OR Doxycycline (if allergic) Strep. pneumoniae + H. influenzae
o Moderate: Amoxicillin + Clarithromycin OR Doxycycline Strep. pneumoniae + H. influenzae + atypicals
o High: Co-amoxiclav + Clarithromycin Strep. + H. influenzae + gram -ve cocci + atypicals
- HOSPITAL
o Early onset: Co-amoxiclav Gram +ve + H. influenzae + gram-ve cocci
o Late onset: Tazocin/Ceftazidime/Ciprofloxacin Pseudomonas
Skin and Tissue Infections – gram +ve, mainly Staph
- Flucloxacillin OR Clarythromycin (if allergic) b-lactamase resistant Staph
(doxycycline if allergic also possible as Staph less sensitive to Clarythromycin than Strep)
- Vancomycin MRSA
Meningitis
- Penicillin Empirical
- Benzylpenicillin/Cefotaxime OR Chloramphenicol (if allergic) Neisseria meningitides
- Cefotaxime OR Chloramphenicol Strep. pneumoniae, H. influenzae
- Amoxicillin AND Gentamycin Listeria
- Think cef for cephalic?
Diarrhoea
- Ciprofloxacin (can cause C. diff) gram –ve cocci
- Metronidazole C. diff