Chapter 5 Infection Flashcards
What antibiotic should be given for the prevention of infection from animal and human bites?
Co-amoxiclav (or doxycycline and metronidazole if penicillin allergic)
What antibiotic should be given if meningitis is suspected? What other medicines might the patient also receive?
Benzylpenicillin
Dexamethasone should be considered (Avoid in septic shock, septicaemia, immunocompromised or following surgery)
Antibacterial therapy for native-valve endocarditis caused by staphylocci
Flucloxacillin - 4 weeks
Antibacterial therapy for prosthetic valve endocarditis caused by staphylocci
Flucoxacillin + rifampicin + low dose gentamicin
6 weeks
Antibacterial therapy for endocarditis caused by sensitive streptococci
Benzylpenicillin
Antibacterial therapy for endocarditis caused by enterococci
Amoxicillin + low dose gentamicin
4-6 weeks
Antibacterial therapy for otitis externa
Consider systemic Abx if spreading cellulitis or patient systemically unwell with flucloxacillin
Antibacterial therapy for otitis media - when do you start treatment? How long is the recommended duration of treatment?
Start if no improvement after 72 hours or if patient is systemically unwell.
Amoxicillin first line
Consider co-amoxiclav if no improvement after 48 hours
Suggested duration of treatment is 5 days
What is the suggested duration of treatment for C.diff?
10-14 days
Suggested antibacterial therapy for biliary-tract infection?
Ciprofloxacin or gent
Antibacterial therapy for bacterial vaginosis?
Oral metronidazole
Antibacterial therapy for uncomplicated chalmydia?
Azithromycin single dose or doxycycline 7 days
Antibacterial therapy for osteomyelitis?
Flucloxacillin - 6 weeks
Abx for low severity CAP?
Amoxicillin
If atypical pathogens are suspected, add clarithromycin or azithromycin
Abx for HAP?
Co-amoxiclav or cefuroxime
Impetigo treatment - small areas of skin infected
Topical fusidic acid for 7 days (max 10 days)
Impetigo treatment when the infection is widespread? What is the patient is penicillin allergic?
Oral flucloxacillin
If penicillin allergic - clarithromycin or clindamycin
Antibacterial therapy for cellulitis? What is the patient is penicillin allergic?
Flucloxacillin (high dose)
If penicillin allergic - clindamycin or clarithromycin
Antibacterial therapy for mastitis during breast feeding?
Treat if severe, systemically unwell, if symptoms do not improve after 12-24 hours of effective milk removal. Flucloxacillin and erythromycin
Aminoglycosides - bacteriostatic or bactericidal?
Bactericidal
What cover do aminoglycosides have?
Mainly gram negative
Some gram positive cover
Inactive against anaerobes
Contra-indication to aminoglycosides
Myasthenia gravis
To avoid excessive dosing in obese patients, gentamicin doses should be based on what?
Use IBW
Target peak level of gentamicin for multiple daily dose regimen?
5-10mg/l
lower for endocarditis 3-5mg/l
What is the important safety information regarding streptomycin dosing?
Side-effects increase after a cumulative dose of 100g which should only be exceeded in exceptional circumstances.
Carbapenems bacterial cover
The carbapenems are beta-lactam antibacterials with a broad-spectrum of activity which includes many gram positive and gram negative bacteria and anaerobes
Which cephalosporin has good activity against pseudomonas?
Ceftazadime
The calcium salt of cetriaxone can potentially cause what complication?
the calcium salt can form a precipitate in the gall bladder which may rarely cause symptoms but these usually resolve when the antibiotic is stopped. Caution in patients with a history of hypercalcuria, history of kidney stones
What generation are cefaclor and cefuroxime?
Second gen
What generation are cefixime, cefotaxime, ceftazidime, ceftriaxone?
Third gen
Antibacterial cover of glycopeptides
Aerobic and anaerobic gram positive bacteria
How does the duration of action of teichoplanin differ from vancomycin?
Has a significantly longer duration of action, allowing once daily administration after the loading dose. Vancomycin can be given every 12 hours
Common side effects of vancomycin with IV use (5 points)
Blood disorders - inc. neutropenia, usually occurs after 1 week, or if cumulative dose reaches 25g Interstitial nephritis Nephrotoxicity Ototoxicity Renal failure
Which glycopeptide is associated with a higher incidence of nephrotoxicity?
Vancomycin is associated with a higher risk of nephrotoxicity than teichoplanin
Clindamycin should be used with caution in what patients?
Middle age-elderly women as higher risk of antibiotic associated colitis
Macrolides should be used with caution in what patients?
Patients with electrolyte disturbances - predisposes to QT interval prolongation
May aggravate myasthenia gravis
Patients with predisposition to QT interval prolongation
Gastro-intestinal side effects are less frequent with which macrolides?
Less frequent with azithromycin and clarithromycin than with erythromycin
5 common side effects of clarithromycin
Dyspepsia, headache hyperhidrosis, insomnia, taste disturbances
True or false - Piptaz is active against Pseudomonas and MRSA?
False
Piptaz is effective in the treatment of pesudeomonas
BUT is not active against MRSA
Why must penicillins NOT be given by intrathecal injection?
The penicillins should not be given by intrathecal injection because they can cause encepthalopathy due to cerebral irritation which may be fatal.
Main side effect with piptaz?
Nausea and vomiting
Co-amoxiclav is associated with a risk of cholestatic jaundice, who is more at risk of this?
More common in patients over the age of 65 years and in men
These reactions have rarely been reported in children
The duration of treatment should be appropriate and should generally not exceed 14 days.
Co-amoxiclav common side effects =
cholestatic jaundice, hepatitis, nausea and vomiting
Discuss the risk of cholestatic jaundice with flucloxacillin
Cholestatic jaundice and hepatitis may occur very rarely, up to two months after treatment with flucloxacillin has been stopped. Administration for more than 2 weeks and increasing age are risk factors. Healthcare professionals are reminded that:
flucloxacillin should not be used in patients with a history of hepatic dysfunction associated with flucloxacillin
and used with caution in those with hepatic impairment
Bacterial cover of ciprofloxacin
Cipro is active against both gram positive and gram negative bacteria. It is particularly active against gram neg
Quinolones may induce convulsions with or without a history of convulsions, what medication prescribed at the same time increases this risk further?
NSAIDS
When is moxifloxacin contraindicated?
Acute myocardial infarction (risk factor for QT prolongation), bradycardia, heart failure with reduced LV ejection fraction,
What is the drug of choice in the treatment and prophylaxis of PCP?
co-trimoxazole
Tetracyclines are contraindicated in what patients?
Patients under 12 years. Should not be given to pregnant women. Caution in myasthenia gravis
Unusual side effect of tetracyclines
Benign intracranial hypertension - headache and visual disturbances may indicate this, should discontinue treatment
Daptomycin monitoring
Monitor creatine kinase before treatment and then weekly during treatment - monitor more frequently if CK elevated more than 5 times the upper limit of normal before treatment
What important safety information is there regarding linezolid?
Severe optic neuropathy may occur rarely, particularly if used for longer than 28 days. Patients should be warned to report symptoms of visual impairment.
Haematopoietic disorders inc. thrombocytopenia, anaemia, leucopenia. FBC monitoring weekly.
