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