Antimicrobial Chemotherapy Flashcards
What is empiric therapy for antimicrobials?
Without microbiology results
Directed - based on antimicrobial results
What are the indications of antimicrobials?
Therapy
Prophylaxis
What are the components of qSOFA?
Systolic BP less than 10, altered mental, respiratory rate greater than 22
What aspects of the patient do you need to consider when prescribing?
Age
Renal function
Liver function
Immunocompromised
Pregnancy
Known allergies
What are the causative bacteria for soft tissue infection?
Streptococcus pyogenes
Staphylococcus aureus
Streptococcus group C or G
E. coli
Pseudomonas aeruginosa
Clostridium species
What are the causative bacteria for pneumonia?
Streptococcus pneumonia
Haemophilus influenzae
Staphylococcus aureus
Klebsiella pneumonia
Moraxella catarrhalis
Mycoplasma pneumonia
Legionella pneumonia
Chlamydia pneumonia
These are atypical
What are the functions of cidal drugs?
Act on cell wall
Kill organisms
e.g - beta lactams
What are the indications for cidal drugs?
Neutropenia, meningitis and endcarditis
What are the functions of static drugs?
e.g macrolides
Inhibit protein synthesis
Prevent colony growth
Requires host immunity to mop up residual infection
Useful in toxin-mediated illness
What are indications for combination therapy?
HIV
TB
Severe sepsis (febrile neutropenia)
Mixed organisms (faecal peritonitis)
What is oral bioavailability?
Ratio of a drug level when given orally compared with level when given IV
When is oral route indicated?
If not vomiting, normal GI function, no shock, no organ dysfunction
When are IV antibiotics indicated?
For severe or deep-seated infection, and when oral route is not reliable
What are the features of immediate hypersensitivity and delayed hypersensitivity?
Immediate - anaphylactic shock
Delayed - rash, drug fever, serum sickness, erythema nodosum, stevens-Johnson syndrome
Mostly with penicillins and cephalosporins
What are the GI adverse effects?
nausea, vomiting, diarrhoea
Clostridium difficile infection
What is likely to cause candida (thrush)?
Broad spectrum penicillins, cephalosporins
What drugs cause liver toxicity?
All drugs, particulary tetracyclines, TB drugs
More likely if pre-existing liver disease
What drugs cause adverse renal effects?
Gentamicin, vancomycin
More like if pre-existing renal disease or on nephrotoxic meds
What drugs cause ototoxicity?
Gentamicin and vancomycin
What drug causes optic neuropathy?
Ethambutol
What drugs cause convulsions, encephalopathy?
Penicillins, cephalosporin
What antibiotics cause peripheral neuropathy?
Isoniazid (TB) and metronidazole
Nitrofurantoin?
What are the haematological adverse effects of antimicrobials?
Marrow toxicity
Megaloblastic anaemia (folate metabolism) - cotrimoxazole
What liasing is required with the laboratory?
Sending appropriate specimens (for culture, direct detection, serology)
Receiving results (preliminary culture results, sensitivity results, final results)
Monitoring (disease activity, therapeutic drug monitoring)
Who is on the antimicrobial management team?
Antibiotic pharmacists
Infectious diseases
Acute medicine
Medical microbiology
Infeciton prevention and control
General practice
Public partner
What are the ways we can ensure correct prescribing of antibiotics?
Antimicrobial guidelines and policies
Audit of quality of antimicrobial prescribing
Education
What are the 4 antibiotics assocaited with C diff?
Ceftriaxone
Co - amoxiclav
Clindamycin
Ciprofloxacin
Which drugs are involved in the inhibition of cell wall synthesis?
Beta lactams (penicillins and cephalosporins)
Glycopeptides (vancomycin and teicoplanin)
hich antibiotics are involved in the inhibition of protein synthesis?
Aminoglycosides: gentamicin
Macrolides (clairithromycin)
tetracyclines (doxycycline)
Oxazolidinones: Linezolid
What drugs inhibit nucleic acid synthesis?
Trimethoprimm
Sulfonamides (sulfamethoxazole)
Quinolones (ciprofloxacin)
What are the main uses of benzylpenicillin, amoxicillin, flucloxacillin, co-amoxiclav, piperacillin/tazobactam?
Benzylpenicillin - soft tissue, pnuemococcal, meningococcal, gonorrhoea, syphilis infections
Amoxicillin - UTI, RTI
Flucloxacillin - Staph aureus
Co-amoxiclav - UTI, RTI, soft tissue infections, surgical wound infections
Piperacillin/tazobactam - neutropenic sepsis
Cephalosporins include cefradine, cefuroxime, ceftriaxone amd ceftazidime. Give examples of main uses for each
Cefradine - UTI and soft tissue infection
Cefuroxime - UTI, RTI, surgical prophylaxis
Ceftriaxone - hospital infections eg bacteraemia, pneumonia, abdominal sepsis
Ceftazidime (like ceftriaxone but also effective against pseudomonas) - pseudomonal infections in hospital and in cystic fibrosis
What are the main uses of gentamicin?
Serious gram negative infections - bacteraemia, endocarditis, neutropenic sepsis
Gram negative bacilli
What is the activity of clairithromycin and erythromycin?
Clairithromycin and erythromycin - streptococci, staphylococci, mycoplasma, chlamydia and legionella
What are the main uses of clairithromycin and erythromycin?
Respiratory infection, soft tissue infection (if penicillin allergic), STD
What is the activity of azithromycin?
Relatively better for gram negative (haemophilus, chlamydia)
What are the main uses of azithromycin?
Chlamydia
What is the activity of ciprofloxacin? and levofloxacin?
(these are quinolones)
Gram negative bacili including pseudomonas - some activity against staphylococci and streptococci
Levofloxacin - enhanced activity against staphylococci and streptococci - less against pseudomonas
Active against pneumococcus, mycoplasma, chlamydia, legionella
What are the main uses for ciprofloxacin?
Complicated UTI
Complicated hospital acquired pneumonia
Some Gi infections
What are the uses of levofloxacin?
2nd or third line for pneumonia
What is the activity of vancomycin and teicoplanin?
Gram positive bacteria only (staph and strep)
What are the main uses for glycopeptides?
MRSA
Patients allergic to penicillin
C.Diff
What is the activity of trimethoprim?
Gram negative bacilli - some activity against staph and strep
What are the main uses of trimethoprim?
UTI
Respiratory infection
MRSA
What is the activity of co trimoxazole?
Broad spectrum
Pneumocystis jiroveci
What are the main uses of co-trimoxazole?
Respiratory infection
PCP - pneumocystics pneumonia, caused by the yeast like fungus pneumocystis jiroveci
What is the activity of clindamycin?
Streptococci
Staphylococcus
Anaerobes
What is clindamycin used for?
Soft tissue infection
Gangrene
What are tetracycline and doxycycline active against?
Streptococci
Staphylococci
Chlamydia
Rickettsiae
Brucella
What is tetracycline and doxycycline used to treat?
Q fever
Brucellosis
Chlamydia
Atypical pneumonia
MRSA
What are the main uses of rifampicin?
TB
MRSA
Meningococcal prophylaxis
Somplicated staph infections
What is the activity of rifampicin?
Mycobacteria
Miningococcus
Staphylococcus
What is the activity for meropenem?
Broad spectrum - including anaerobes, pseudomonas
What are the main uses of meropenem?
2nd or 3rd line for hospital infections
What is the activity of metronidazole?
Anaerobes
Protoza
Diardia
What are the main uses of metronidazole?
Surgical infections
Giardiasis
Amoebiasis
Trichomonal infections
What is the activity of linezolid?
Gram positive bacteria only
(streptococci, staphylococci, enterococci)
2nd line agent for MSSA, MRSA, VRE
What are the main uses of metrodonidazole?
2nd line agent for MSSA, MRSA, VRE
What is the activity of daptomycin?
Gram-positive bacteria only (strep, staph and enterococci)
What are the main uses of daptomycin?
2nd line agent for MSSA, MRSA, VRE
What is the activity of tigecycline?
Very broad spectrum including MRSA, ESBL, anaerobes
What are the main uses of tigecycline?
3rd line inta-abdominal sepsis, soft tissue infections
What are the azoles and what are they active against?
fluconazole: Candida, some resistance
itraconazole: Candida & Aspergillus
voriconazole: Candida & Aspergillus
What are polyenes and what are they active against?
Amphotericin - candida and aspergillus
Nystatin - candida
What are the echinocandins and what are they effective against?
caspofungin, anidulafungin, micafungin: Candida, Aspergillus
What is terbinafine effective against?
Tinea, nails
