Random Notes Flashcards
2 main classes of gram positive cocci
Staphyloccocus and streptococcus
How are streptococci differentiated
Haemolysis
How are staphylococcus differentiated
Coagulase test
Commonest cause of pneumonia
Streptococcus pneumoniae
Treatment for strep pneumoniae
Penicillin
2 main groups of alpha haemolytic streptococcus
Strep pneumoniae and Strep viridans
Common cause of endocarditis
Strep viridans
2 main groups of beta haemolytic streptococcus
Group A Strep and Group B strep
Most pathogenic strep
Group A strep (strep pyogenes)
Treatment for beta-haemolytic strep
Penicillin/amoxicillin
Examples of non-haemolytic strep
Enterococcus (faecalis and faecium)
Common cause of UTI’s
Enterococcus faecalis
Catalase positive cocci
Staphylococcus
Catalase negative cocci
Streptococcus
Coagulase positive organisms
Staph aureus
Coagulase negative organisms
All staph apart from staph aureus
Common cause of infected prosthetic heart valves and joints
Staph epidermidis (coagulase negative staph)
Treatment for coagulase negative staph
Vancomycin
Common cause of skin infections, abscesses, resp infections and food poisoning
Staph aureus
The most common cause of bacteraemia
Staph aureus
Treatment for staph aureus
Flucloxacillin
Treatment for MRSA
Co-trimoxazole and clindamycin
Gram negative cocci that causes bacterial meningitis
Neisseria meningitis
Gram negative cocci that causes gonorrhoea
Neisseria gonorrhoea
Gram negative cocci that look like E.coli when cultured
Coliforms
Common gut commensals
E.coli, klebsiella and enterococcus
Common gut pathogens
Verotoxin producing E.coli (E.coli 1057), shigella and salmonella
Treatment for coliform infection
Gentamycin
Examples of gram negative bacilli that are strict aerobes
Legionella (gram- bacilli)
pseudomonas (gram- bacilli)
Spiral/curved aerobic gram negative bacilli
Vibro cholera, campylobacter and H. pylori
Gram negative organism that commonly causes chest infections (esp in COPD)
Haemophilus influenza
Examples of strict anaerobes
Clostridium (gram+ bacilli)
Bacteroides (Gram- bacilli)
Gram positive organism that commonly causes C. diff
Clostridium
Treatment for strict aerobes
Metronidazole
Treatment for TB
Rifampicin, isonazide, pyrazinamide and ethambutol
Causative organism of TB
Mycobacteria
Causative organism of syphilis
Treponema pallidum
Cause of Lyme disease
Borrelia burgdorferi
Class of organisms that do not stain
Spirochaetes
Enzyme that is resistant to the early penicillins (like amoxicillin)
Beta-lactamase
Enzyme that is resistant to all penicillin and cephalosporins
Extended spectrum beta-lactamase
Enzyme that is resistant to all penicillin, cephalosporins and carbapenems
Carbapenemase
Staph aureus that is resistant to flucloxacillin
MRSA
Antibiotics that work on the cell wall
Penicillin, cephalosporins and glycopeptides
Penicillin that is used for gram positive organisms
Flucloxacillin
Penicillin that is used for gram positive and gram negative organisms
Amoxicillin, co-amoxiclav, tazocin
Penicillin that is used for gram negative organisms
Temocillin
Used first line for staph aureus
Flucloxacillin
Basically treats everything apart from pseudomonas and MRSA
Co-amoxiclav
Reserved for intensive care but can basically treat everything apart from MRSA
Tazocin
Only active against coliforms (gram negative organisms)
Temocillin
Broad spectrum antibiotics that are avoided in hospitals as they can cause C. diff
Cephalosporins
Examples of glycopeptides
Vancomycin and teicoplanin
What type of bacteria are glycopeptides active against
Gram positive bacteria (e.g. staph, strep, clostridium and MRSA)
Antibiotics that inhibit protein synthesis
Macrolides, tetracyclines and aminoglycosides
The only group of protein synthesis inhibiting antibiotics which are bacteriocidal
Aminoglycosides
Examples of macrolides
Erythromycin, clarithromycin and azithromycin
How are macrolides excreted
By the liver NOT the urine
Example of an aminoglycoside
Gentamicin
How must gentamicin be given
IV
Side effects of gentamycin
Kidney/renal damage, damage to CN VII causing deafness and dizziness
Antibiotics that work on bacterial DNA
Metronidazole, trimethoprim and fluoroquinolones
Used to treat true anaerobic infections
Metronidazole
Used for pneumocystis jirovecii
Co-trimoxazole
Examples of fluoroquinolones. Note these are severely restricted in Tayside due to risk of C. diff
Ciprofloxacin and levofloxacin
Can cause tendonitis
Ciprofloxacin
Interacts with alcohol
Metronidazole
Antibiotics to avoid (the 4 C’s)
Ciprofloxacin, co-amoxiclav, cephalosporins and clindamycin
Treatment for mild/moderate CAP
IV/PO Amoxicillin (PO doxycycline if allergic)
Treatment for severe CAP
IV Co-amoxiclav + clarithromycin OR doxycycline PO
IV levofloxacin if allergic
Treatment for non-severe HAP
PO Amoxycillin and metronidazole
If penicillin allergic PO Co-trimoxazole + Metronidazole
Treatment for severe HAP
IV Amoxicillin + Metronidazole + Gentamicin
If penicillin allergic: IV Co-trimoxazole + Metronidazole +/- Gentamicin
Specific treatment for Pneumococcal Pneumonia
Amoxicillin, Benzylpenicllin or cephalosporin
Specific treatment for Staphylococcal Pneumonia
Flucloxicillin
If MRSA suspected add vancomycin
Specific treatment for Klebsiella Pneumonia
Cefotaxime or Imipenem
Specific treatment for Pseudomonas Pneumonia
Anti-pseudomonal penicillin, cerftazidime, meropenum, or ciprofloxacin + aminoglycoside
Specific treatment for Mycoplasma Pneumonia
Clarithromycin or Tetracycline or Fluroquinolone (e.g. ciprofloxacin or norfloxacin)
Specific treatment for Legionella Pneumonia
Clarithromycin + rifampicin OR
Fluoroquinolone (e.g. cirporfloxin) for 2-3 weeks
Specific treatment for Chlamydophilia Pneumonia
Tetracycline or Clarithromycin
Specific treatment for Chlamydophilia Psittaci Pneumonia
Tetracycline or Clarithromycin
Specific treatment for Viral Pneumonia
Ciprofloxacin and Co-Amoxiclav.
Prophylactically oseltamivir is given
Specific treatment for Pneumocystis Pneumonia (PCP)
High dose co-trimoxazole or pentamidine.
Steroids are beneficial if severe hypoxaemia. Prophylaxis often used.
Treatment for Native valve (Subacute) Endocarditis (enterococcus)
IV Amoxicillin + Gentamicin, b.d.
Treatment for Native valve severe sepsis (Acute) Endocarditis (staph aureus)
IV Flucloxacillin
Treatment for Prosthetic valve or Suspected MRSA Endocarditis (staph epidermidis)
Vancomycin IV + Rifampicin PO b.d. + Gentamicin IV
Native valve severe sepsis + risk factors for resistant pathogens Endocarditis
Vancomycin IV + Meropenem IV
Explain CURB 65 Score
Confusion Urea >7 mmol/L Resp. Rate ≥ 30/min Bp <90mmHg (systolic) or ≤60mmHg (diastolic) 65 Age ≥65 1 point for each criteria 0-2 = Mild/Moderate CAP 3-5 = Severe CAP
Mechanism of Penicillins, Glycopeptides and Cephalosporins
Inhibit cell wall formation
Mechanism of Macrolides (e.g. erythromycin), Aminoglycosides and Tetracyclines
Inhibit protein synthesis
Mechanism of Quinolones (e.g. ciprofloxacin), Trimethoprim and Metronidazole
Inhibit DNA synthesis
Mechanism of Rifampicin
Inhibit RNA synthesis
Gram+ organisms stain…
Purple
Stain well due to thick peptidoglycan layer
Gram- organisms stain…
Pink
Thinner peptidoglycan layer doesn’t retain stain well
Endotoxin is produced by…
Gram-
Part of cell wall
Exotoxin is produced by…
Gram+
Exported from cell
Gram+ cocci in chains are?
Strep