Infection Flashcards
What antibiotics are not recommended in children?
Tetracyclines are CI in those under 12
Quinolones cause arthropathy
What antibiotics are not recommended in elderly?
The elderly are the most susceptible to C.difficile infections and have the greatest risk of developing it with Clindamycin
What antibiotics are not recommended in allergies?
Penicillin and Cephalosporins
Metronidazole for dental infections or macrolides
What antibiotics are not recommended in renal impairment?
Nephrotoxic - Aminoglycosides and Glycopeptide
Avoid tetracyclines except (Doxycycline and Minocycline) and Nitrofurantoin if eGFR <45mL/min
What antibiotics are not recommended in hepatic impairment?
RIP and teracyclines
Metronidazole if severe impairment
Co-amoxiclav and Flucloxacillin can cause cholestatic jaundice if used >14 days
What antibiotics are not recommended in pregancy?
Tetracyclines CI
Avoid MCAT (Metronidazole, Chloramphenicol, Aminoglycosides and Tetracyclines), Quinolones and Sulfonamides, and avoid Nitrofurantoin at term
Amoxicillin and Cephalosporins are safe
What side effects are associated with clindamycin?
Antibiotic associated colitis - can be fatal and must need to be reported
What side-effects are associated with trimethoprim and co-trimoxazole?
Trimethoprim - Blood dyscrasias, Hyperkalaemia and Anti-folate
Co-trimoxazole - SJS, toxic epidermalnecrolysis (similar to Lamotrigine)
What side effects are associated with chloramphenicol?
Blood dyscrasias and grey baby syndrome (avoid in pregnant women)
What indications can metronidazole be used in?
Metronidazole can be used in H.pylori, anaerobic dental infections, rosacea, antibiotic associated colitis, bacterial vaginosis and trichiomoniasis.
What side-effects can occur with metronidazole?
GI and taste disturbances, furred tongue and oral mucositis
What counselling should be given to patients taking metronidazole?
Take 1 tablet with or after food
Avoid alcohol for 48 hours after finishing the course
What side effects are associated with nitrofurantoin?
Nausea and peripheral neuropathy in those suffering from renal impairment
What counselling should be given to patients who take nitrofurantoin?
It should be taken with or after food
It may colour the urine yellow or brown
What are the indications for gentamicin?
Endocarditis, Complicated UTI, pyelonephritis and severe sepsis
Where are each of the 5 aminoglycosides indicated?
G-Gentamicin - for Psuedomonas aeruginosa
A- Amikacin - for gentamicin resistant Bacilli
N- Neomycin - parenterally toxic - for bowel cleanses
T- Tobramycin - inhaled for pseudomonas infections in CF
S- Streptomycin - reserved for mycobacterium for TB
Which two classes of antibiotics can gentamicin be given with as blind therapy?
Gentamicin + metronidazole or penicillin
When should gentamicin be avoided?
Gentamicin should be avoided in renal impairement <20ml/min and those suffering from gram positive endocarditis and HACEK bacteria
What is the peak concentration of gentamicin
a) For non-endocarditis
b) For endocarditis
a) 5-10mg/mL
b) 3-5mg/mL
What is the trough concentration of gentamicin
a) For non-endocarditis
b) For endocarditis
a) <2mg/mL
b) <1mg/mL
What are the side-effects of gentamicin?
Nephrotoxicity, neuromuscular transmission impairment, electrolyte disturbances (hypomagnesia, hypocalcaemia and hypokalaemia) and peripheral neuropathy
What drugs does gentamicin interact with?
Gentamicin can cause permanent ototoxicity with:
cisplatin and loop diuretics
It can also cause nephrotoxicity with ciclosporin, tacrolimus and vancomycin
What is vancomycin indicated for?
MRSA
Name three examples of glycopeptides
Vancomycin, teicoplanin and televancin (for HAP)
How often are patients required to be monitored on vancomycin?
Patients are required to be monitored after every 3-4 doses or after a dose change
What are some of the indications for tetracyclines?
LRTIs, rosacea, acne, malaria and chlamydia
Which tetracycline can be used for both malaria and chlamydia?
Doxycycline
What side-effect is associated with tetracyclines and what should be done if this occurs?
Intercranial hypertension- the medication should be stopped
What are the counselling points for tetracyclines?
DOT- NO milk
DLM- milk
DD- avoid sunlight
DMT- take whilst upright with a full glass of water
What are the indications for quinolones?
LRTIs and UTIs
What are the SEs of quinolones?
STAQ
What interactions occur with quinolones?
Seizure threshold - MAST QT
NSAIDs+ Quinolones -> can cause seizures
QT inerval prolongation -MASTAQ
What counselling needs to be given to patients on quinolones?
Ciprofloxacin + Norfloxacin -> avoid milk and indigestion remedies
Ofloxacin -> Avoid sunlight
Others -> Avoid antacids
Potential impaired driving
What are the indications for macrolides?
H.pylori, RTIs and skin and soft tissue infection
What are the side effects of macrolides?
G- GI
H- Hepatotoxicity
O- Ototoxicity at high doses
Q- QT interval prolongation
What interactions occur with macrolides?
Warfarin- bleeding risk
Statins - myopathy
Digoxin - CRASED
What are examples of narrow spectrum Beta-lactamase sensitive antibiotics?
Phenoxymethylpenicillin or Benzylpenicillin
What are examples of broad spectrum Beta-lactamase sensitive antibiotics?
Ampicillin
Amoxicillin
What are examples of Penicillinase resistant antibiotics?
Flucloxacillin
What are examples of antipseudomonal antibiotics?
Piperacillin + Tazobactam or Ticaricillin + Clavulinic acid
What are the possible outcomes for a possible penicillin allergy?
1) True allergy - anaphylaxis, urticaria -> do not give any cephalosporins, carbapenems, penicillins or cephalosporins
2) Mild rash - may take up to 72 hours for it to appear
Which route should penicillin not be administered and why?
Intrathecal route- can cause encephalopathy and may be fatal
What are the complication(s) that may arise from broad-spectrum antibiotics such as ampicillin and amoxicillin?
Can cause a maculopapular rash in glandular fever and can also cause antibiotic-associated colitis
Where are narrow spectrum lactam sensitive antibiotics used?
Benzylpenicillin -> Meningitis (IV only as not gastrostable)
Phenoxymethylpenicillin -> Streptococci induced sore throat
Where are penicillinase-resistant antibiotics used?
Penicillinase-resistant antibiotics such as flucloxacillin are used in skin conditions such as impetigo and cellulitis for pathogens that are penicillin resistant
What is the dose of flucloxacillin? What side-effect can it cause?
xmg QDS before food. It can cause cholestatic jaundice if used for more than 14 days
What are the treatments for psuedomonal bacteria?
Piperacillin and Tazobactam or Ticaricillin with Clavulanic acid
When are cephalosporins not used?
Cephalosporins should not be used if a patient has immediate penicillin hypersensitivity
Which antibiotics cause C.difficile colitis?
Ampicillin, Amoxicillin, Co-amoxiclav, 2nd and 3rd gen cephalosporins, quinolones, and clindamycin
What can be used to treat C.difficile colitis?
Metronidazole for 10-14 days.
If this does not help then oral vancomycin or fidaxomicin
What can be used to treat endocarditis?
Amoxicillin +/- low dose gentamicin
Strep = Benzylpenicillin
Staph = Flucloxacillin
MRSA = Vancomycin
What can be used to treat CAP?
Mild CAP - Amox/Clarithro/Doxy
Moderate CAP - Amox + Clarithro or Doxy
Severe - Benzylpenicillin + Doxy or Clarithro
Add fluclox or vanco
What can be used to treat HAP?
<5 days or early onset HAP - Cefuroxime or Co-amoxiclav
>5 days or severe - broad spectrum cephalo or antipseudomonal penicillin or quinolone
Add vanco or genta
What can be used to treat meningitis?
Treatment for meningitis includes-
Benzylpenicillin
If penicillin allergic, then cefotaxime
If immediate penicillin allergy then chloramphenicol
What can be used to treat osteomyelitis?
Flucloxacillin or Clindamycin if penicillin allergic
What can be used to treat impetigo?
If a small area, fusidic acid. If it is a large area, it is flucloxacillin
What can be used to treat cellulitis?
Flucloxacillin
What can be used to treat animal bites?
Co-amoxiclav or Doxycycline and Metronidazole
What can be used to treat MRSA?
Tetracycline, Clindamycin or Vancomycin or Linazolid if very severe
What is Linezolid, indications, SEs and interactions?
Linezolid is a MAOi, an alternative option for MRSA. It can cause blood dyscrasias and occular neuropathy if used for more than 28 days. It interacts with sympathomimetics causing a hypertensive crisis
What can be used for streptococcal sore throats?
Pen V or if severe, then initiate with Benzylpenicillin
What can be used for sinusitis?
Amox/Clarithro/Doxy
What can be used for otitis externa?
Fluclox or Clarithromycin if penicillin allergic
What can be used for otitis media?
Amox or Clarithromycin if penicillin allergic
Name some antifungals
Voriconazole
Itraconazole
Ketoconazole
Amphoterecin B
Name some side-effects associated with these antifungals
Voriconazole - can cause skin cancer - avoid direct sunlight or lamps . Patients should carry an alert card Itraconazole - interaction with antacids. It can cause heart failure and is hepatotoxic
Ketoconazole - fatal hepatotoxicity
Amphoterecin B - must be given by brand as bioavailability differs
What can be used to treat:
Oral thrush?
Vaginal thrush?
Oral thrush - nystatin or miconazole
Vaginal thrush - clotrimazole or fluconazole
What can be used for tinea infections?
Miconazole, Clotrimazole or Terbinafine
What can be used for nail infections?
Amorolfine nail lacquer
What can be done to prevent mosquito bites?
DEET - after sunscreen
Permethrin coated nets
Cover up with long sleeve clothing after dusk
What can be used for malaria prophylaxis?
Doxycycline Atovaquone and Proguanil Chloroquine and Proguanil Chloroquine Mefloquine
Which malaria prophylaxis should be given in: Epilepsy Renal Impairment Pregnancy Warfarin
Epilepsy - avoid mefloquine and chloroquine
Renal Impairment - Doxycycline and Mefloquine
Pregnancy - Chloroquine and proguanil - give 5mg folic acid with proguanil
Warfarin - take prophylaxis 2-3 weeks before, have INR stabilised prior departure
What is the treatment regime for: Doxycycline Malarone Chloroquine and proguanil Mefloquine Chloroquine
Doxycycline - 1-2 days before, 4 weeks after - daily
Malarone - 1-2 days before, 1 week after - daily
Chloroquine and proguanil - 1 week before, 4 weeks after
Mefloquine - 2-3 weeks before, 4 weeks after - weekly
Chloroquine - 1 week before, 4 weeks after - weekly
What is the standby treatment for malaria?
Quinine
