Infections Flashcards
Are narrow- spectrum antibacterials preferred or broad- spectrum?
Narrow- spectrum preferred
UNLESS it is clear clinically whats causing infection
Thats why you should test to see what organism is causing it
What does the dose of antibacterial drugs depend on? (5)
- age
- weight
- hepatic function
- renal function
- severity of infection
What does the route of administration of an antibacterial drug depend on? (1)
severity of infection
What route of administration is usually used for life- threatening infections? (1)
IV
What does duration of therapy depend on? (2)
- type of infection
- the response of the infection to treatment
What are the disadvantages of un needed prolonged courses of antibacterial drugs? (3)
- encourage resistance
- may lead to side- effects
- costly
What types of antibacterials are suitable for use during pregnancy? (3)
- penicillins
- cephalosporins
- nitrofurantoin may be used BUT avoid at term
What antibacterials should be avoided during pregnancy? (3)
- diaminopyrimidines
- quinolones
- trimethoprim PARTICULARLY in 1st trimester
What antibacterials should be avoided in renal impairment? (2)
- tetracyclines
- nitrofurantoin
If wanting to give aminoglycosides to someone with renal impairment, what must be done? (2)
Reduce the dose
As aminoglycosides are excreted by the kidney
Provide some examples of aminoglycosides: (5)
- amikacin
- gentamicin
- neomycin
- streptomycin
- tobramycin
What is the mechanism of action of aminoglycosides? (4)
Bactericidal
Irreversibly binding to ribosomes
Inhibit protein synthesis
Causes fissure which ENHANCES UPTAKE of ANTIBIOTIC & LEAKAGE of cell contents
What type of bacteria are aminoglycosides active against? (2)
Broad- spectrum
Mostly against Gram - ve
But also some Gram + ve
What are the indications of aminoglycosides? (4)
- CNS infections: endocarditis, septicaemia, meningitis
-Biliary-tract infection
- Prostitis
- Pneumonia
Which aminoglycosides are active against P. aeruginosa? (3)
Amikacin, Tobramycin and Gentamicin
Which aminoglycoside is active against M. tuberculosis? (1)
Streptomycin
What are side effects of aminoglycosides? (8)
- may impair neuromuscular transmission
- irreverisible ototoxicity
- nephrotoxicity
- nausea
- vomiting
- antibiotic associated colitis
- peripheral neuropathy
- electrolyte disturbances
MINNVAPE
Which patients should we take caution in when giving aminoglycosides? (1)
And we should also take caution when pts taking aminoglycosides with what drugs? (2)
caution in patients with clinical muscular weakness, e.g. myasthenia gravis
avoid concomitant use with ototoxic drugs, e.g. cisplatin and furosemide
avoid concomitant use with nephrotoxic drugs e.g. vancomycin and ciclosporin
What are examples of ototoxic drugs?
cisplatin and furosemide
What are examples of nephrotoxic drugs?
vancomycin and ciclosporin
Why are aminoglycosides given parenterally for systemic infections?
they are not absorbed from the gut
Although aminoglycosides are given parenterally, neomycin can be given orally for two indications. What can neomycin be given orally for? (2)
bowel sterilisation before surgery
liver failure
Are once-daily doses of aminoglycosides preferred over multiple daily doses?
Yes
What is the aminoglycoside of choice in the UK?
Gentamicin
What is the therapeutic range of gentamicin like?
Narrow
What should the post- dose (peak) serum concentration be for multiple daily dose regimens of gentamicin?
How would this change in endocarditis? (2)
Measured one hour after dose
5- 10mg/ L
3 - 5 mg/L for endocarditis
(High levels suggest potential toxicity; reduce the dose accordingly)
What should the pre- dose (trough) concentration be for multiple daily dose regimens of gentamicin?
How would this change in endocarditis? (2)
This is measured just before the next scheduled dose.
< 2mg/ L
<1mg/ L for endocarditis
High levels suggest inadequate drug clearance; adjust dosing interval.
What should we monitor in all aminoglycosides? (3)
Renal function (as can cause nephrotoxicity)
Auditory and vestibular function (as can cause irreversible ototoxicity)
Serum- aminoglycoside in certain groups of patient
In which patients should serum- aminoglycoside concentration be determined? (6)
Elderly
Those receiving parenteral treatment
Renal impairment
Obesity
Cystic fibrosis
Those receiving high doses
What warning signs should patients on aminoglycosides look out for and what should they do if they see these signs?(3)
Nephrotoxicity
Ototoxicity (hearing impairment or disturbance)
Dehydration (ensure patient is well hydrated before treatment to prevent dehydration)
If these signs are seen, patients should REPORT all to their doctor immediately.
Can aminoglycosides be given in pregnancy? (2)
Risk of auditory and vestibular nerve damage in 2nd and 3rd trimester
Avoid unless essential
What are drug interactions of aminoglycosides? (2)
Increased risk of ototoxicity when given with furosemide (loop diuretics), vancomycin,cisplatin
Increased risk of nephrotoxicity when given with ciclosporin, tacrolimus, vancomycin
What are signs of nephrotoxicity? (2)
Low urine output/creatinine clearance
high serum creatinine/urea
(Make sure to assess renal function of patient before treatment; correct dehydration)
What reaction can some batches of aminoglycosides cause? (3)
histamine-related adverse drug reactions
Monitor for signs of histamine-related reactions
Exercise caution with concomitant drugs known to cause histamine release, especially in children and severe renal impairment.
What are the five generations of cephalosporins? (4)
1st cefalexin, cefradine, cefadroxil (bd)
2nd cefaclor, cefuroxime
3rd cefixime, ceftriaxone
5th ceftaoline fosamil
What is the mechanism of action of cephalosporins? (3(
Bactericidal
Prevent cell wall synthesis
By binding to enzymes called penicillin binding proteins (PBPs)
What types of bacteria are cephalosporins active against? (1)
Both Gram -ve and Gram +ve
What indications are cephalosporins given for?(4)
Pneumonia
Meningitis
Gonorrhoea
UTIs
What are the side effects of cephalosporins?
Antibiotic associated colitis (rare but more common with 2nd and 3rd generation)
Which generations of cephalosporins tend to be given orally?
1st and 2nd
Which generation of cephalosporins tend to be given parenterally? Which one is an exception? (2)
3rd and 5th
except for cefixime in the 3rd generation, which is orally active
Cephalosporins should not be administered to individuals with a history of what hypersensitivity? What would you do if no alternative is available? (2)
with a history of immediate penicillin hypersensitivity.
Alternatives: If no alternative is available and essential, consider 3rd generation cephalosporins or cefuroxime (2nd generation)
Should cefuroxime (2nd gen) be given with or without food?
Needs to be given with food to maximise absorption as it is POORLY absorbed
Which generations of cephalosporins are less susceptible to inactivation by beta- lactamases?
2nd and 3rd generations
What are examples of glycopeptides?
Vancomycin, Teicoplanin, Telavancin
What is the mechanism of action of glycopeptides? (2)
Binds to cell wall precursor components
Inhibits cell wall synthesis
What bacteria’s are glycopeptides active against? (1)
Aerobic and anaerobic gram+ ve bacteria including MRSA
What are the indications of glycopeptides? (3)
Clostridium difficile infection
Endocarditis
Surgical prophylaxis when high risk of MRSA
What are the side effects of glycopeptides? (9)
Nephrotoxicity
Ototoxicity
Blood disorders
Nausea
Chills
Fever
Rashes
Steven-Johnson syndrome
Flushing of the upper body
Who should we avoid vancomycin in? (2)
The elderly
patients with a history of auditory problems
What should we monitor when administering glycopeptides? (6)
In all glycopeptides, monitor:
blood counts
hepatic function
renal function
urinalysis
plasma levels
auditory function in elderly
Are glycopeptides narrow or broad spectrum?
Narrow spectrum
Are vancomycin and teicoplanin given orally for systemic infections?
No
Why may loading doses be required for vancomycin?
Have a long half- life
What should the pre- dose “trough” level be for vancomycin? How can this change for endocarditis, less sensitive MRSA strains, or complicated S. aureus infections? (2)
10-15mg/mL
15-20mg/L for endocarditis, less sensitive MRSA strains, or complicated S. aureus infections
What are warning signs of glycopeptides? What must patients do if they experience these? (6)
Ototoxicity (hearing loss, vertigo, dizziness, tinnitus)
Red man syndrome (flushing of the upper body)
Blood disorders (fever, sore throat, mouth ulcers, unexplained bleeding or bruising)
Phlebitis (drug irritates tissue causing inflammation)
Nephrotoxicity (elevated serum creatinine levels)
Skin disorders (rashes, pruritic, SJS)
Patient must report all to a doctor immediately
What can happen if glycopeptides are administered too quickly?
Hypotension and anaphylaxis can occur
Can glycopeptides be given in pregnancy? (2)
Manufacturer advices avoiding
If used, it is essential to monitor plasma concentration. This is to minimise foetal toxicity
Can glycopeptides be given when breastfeeding?
It is present in milk but significant absorption is unlikely
What are interactions of vancomycin (glycopeptides)? (3)
NEPHROTOXICITY AND OTOTOXCITY: Ciclosporin, aminoglycosides, polymyxin antifungals
OTOTOXICTY: loop diuretics
ENHANCES effects of suxamethonium
What is the mechanism of action of clindamycin (a lincosamide)? (3)
Bacteriostatic
Binds to ribosomes
Inhibits cell wall protein synthesis
What types of bacteria is clindamycin active against?
Gram +ve aerobes and anaerobes
What are the indications of clindamycin? (4)
Staphylococcal joint and bone infections
Intra-abdominal sepsis
Cellulitis
Skin and soft- tissue infections
What individuals require monitoring when administering clindamycin? (2)
Infants(monitor hepatic and renal function)
those being treated for > 10 days
What are side effects of clindamycin? (7)
GI disturbances
Oesophageal disorders
Taste disturbances
Jaundice
Blood disorders
Rashes
SJS
What should a patient on clindamycin do if they develop diarrhoea? (2)
DISCONTINUE treatment immediately if diarrhoea develops and CONTACT GP
as antibiotic associated colitis can be fatal
Who should we not use clindamycin in?
Patients with existing diarrhoea
What type of individuals is antibiotic-associated colitis more common in? (2)
Middle-aged and elderly women
Especially post-operation
What are examples of macrolides? (3)
erythromycin
azithromycin
clarithromycin
What is the mechanism of action of macrolides? (2)
Bacteriostatic
Binds to ribosomes
Inhibiting cell wall protein synthesis
What antibacterial is a good alternative in penicllin-allergic patients? (2)
Macrolides
have similar activity to penicillin
What are indications of macrolides? (3)
respiratory tract infections e.g. whooping cough, lyme disease
H Pylori
Skin and soft tissue infections
What are side effects of macrolides (4)
Gi disturbances mainly with erythromycin
hepatotoxicity
rash (SJS)
ototoxicity at high doses
What are contraindications of macrolides? (2)
may aggravate myasthenia gravis
use in caution with patients predisposed to QT interval prolongation
i.e electrolyte disturbances & taking drugs that prolong QT interval such as sotalol
What is telithromycin?
A derivate of erythromycin
What are side effects of telithromycin? (4)
May cause visual disturbances
transient loss of consciousness
affect performance of skilled tasks and driving
hepatotoxicity: discontinue treatment and seek medical advice
Are macrolides broad or narrow spectrum?
broad
How should azithromycin be taken? (2)
OD
leave a 2- hour gap before food/indigestion remedies
How should clarithromycin be taken?
BD
What is a side effect of clarithromycin?
taste disturbance
How should erythromycin be taken? (2)
QDS
leave a 2- hour gap before indigestion remedies
What can spiramycin cause?
Toxoplasmosis
Are erythromycin and clarithromycin potent enzyme inhbiitors or inducers?
potent enzyme inhibitors
Why can macrolides interact with warfarin? (2)
potent enzyme inhibitors
increased risk of bleeding
why can macriolides interact with statins?
increased risk of myopathy
What is the mechanism of action of metronidazole? (5)
Bactericidal
a pro- drug
the active form binds to DNA
disrupts its helical structure
inhibiting bacterial DNA synthesis
What types of bacteria does metronidazole have high activity against?
anaerobic bacteria and protozoa
What are the indications of metronidazole? (5)
ALTERNATIVE TO PENICILLIN for many ORAL infections where patients are either ALLERGIC to penicillin or the infection is being caused by PENICILLIN- RESISTANT anaerobes
H. Pylori eradication
Acute oral infections
Leg ulcers
Pressure sores
What are side- effects of metronidazole?(5)
GI disturbances
Taste disturbances
Furred tongue
Oral mucositis
Anorexia
When should we monitor patients on metronidazole?
if treatment exceeds 10 days
How should we take metronidazole? (2)
Take with or just after food
Avoid alcohol whilst taking and for up to 48 hours after. Can cause disulfiram- like reaction with alcohol i.e nausea and vomiting.
Which penicillins are beta- lactamase sensitive? (3)
pen V
Pen G
Amoxicillin
Which penicillin is penicillinase- resistant?
Flucloxacillin
What is the mechanism of action of penicillins? (2)
Prevent peptidoglycan cross- linking
Inhibit bacterial cell wall synthesis
Which bacterias is penicillin active against? (2)
Gram - ve and Gram + ve
What are the indications of penicillins? (5)
Oral infections
Otitis media
Cellulitis
Respiratory tract infections
Pneumonia
What are side effects of penicillins? (6)
Hypersensitivity (1- 10%)
Anaphylaxis (<0.05%)
Maculopapular rash is common with ampicillin and amoxicillin
Diarrhoea
Antibiotic associated colitis
CNS toxicity: rare but serious. Caused by encephalopathy due to cerebral irritation, occurs at high doses or renal impairment
Maculopapular rash is common with which penicillins? (2)
Ampicillin and Amoxicillin
What the side effect of penicillins CNS toxicity caused by? When does it occur? (2)
Caused by encephalopathy due to cerebral irritation
occurs at high doses or renal impairment
Which patients prescribed penicillin are at higher risk of experiencing an anaphylaxis reaction? (2)
with a history of penicillin allergy
patients with atopic allergy e.g. asthma, hay fever, eczema
A patient experiences a rash 72 hours after administering penicillin. Is this anaphylaxis?
No
What is common with most- broad spectrum antibiotics?
Diarrhoea/ antibiotic associated colitis
How should penicillins be taken? (2)
On an empty stomach
An hour before food or 2 hours after
What is a side effect of co- amoxiclav? Who is this side effect more common in?
Cholestatic jaundice
More common in patients above the age of 65 years and in men
You cannot give co- amoxiclav for more than how many days?
14 days
Is jaundice fatal?
No. It is usually self- limiting and very rarely fatal
What may occur very rarely to patients taking flucloxacillin up to two months after treatment? (2)
Cholestatic jaundice and hepatitis
Particularly if they took it for more than 2 weeks and the older u are, the higher the risk
In which patients should flucloxacillin not be used in? (3)
Hypersensitivity reactions to beta- lactam antibacterial
In patients with a history of hepatic dysfunction associated with flucloxacillin
Use with caution in patients with hepatic impairment
What are examples of quinolones? (5)
Ciprofloxacin
Levofloxacin
Moxifloxacin
Norfloxacin
Ofloxacin
What is the mechanism of action of quinolones?
Inhibits enzymes necessary for bacterial DNA replications
Which bacteria’s are quinolones active against?
Gram +ve and Gram -ve
What are indications of quinolones? (4)
Respiratory tract infections
Anthrax
Gonorrhoea
UTIs
Which patients should quinolines be used with caution in? (5)
history of joint disorders
epilepsy or predisposition to seizures
G6PD deficiency
Myasthenia gravis
children or adolescents (risk of arthropathy)
Can quinolones be used in pregnancy?
No, avoid
What should we counsel on when they are taking quinolines? (2)
Avoid exposure to EXCESSIVE sunlight
Avoid concomitant use with NSAIDs (increased convulsion risk)
What are side effects of quinolines? (7)
GI disturbances (rarely antibiotic associated colitis)
headache
dizziness
moxifloxacin associated with QT interval prolongation
life- threatening hepatotoxicity
may induce convulsions in pts with/ without history. Also if they take NSAIDs at same time.
Rare risk of tendon damage within 48 hours of starting treatment
Who is at risk of experiencing the rare risk of tendon damage caused by quinolones? (2)
patients over 60
concomitant use of corticosteroids
What are examples of diaminopyrimidines? (2)
Co- trimoxazole
Trimethoprim
What is the mechanism of action of diaminopyrimidines?
Block different steps in the synthesis of nucleic acids essential to many bacteria
Which bacterias are diaminopyrimidines effective against?
Gram +ve and Gram -ve
What are indications of diaminopyrimidines? (4)
Pneumonia
Respiratory tract infections
Shigellosis
UTIs
What are side effects of diaminopyrimidines? (2)
SJS
blood disorders especially in the elderly
What are contraindications of diaminopyrimidines? (5)
Blood dyscrasia
Asthma
GP6PD deficiency
Elderly
Predisposition to folate deficiency or hyperkalaemia
Can we give diaminopyrimidines in pregnancy?
Avoid in first trimester of pregnancy (folate antagonist is teratogenic)
What should we monitor for patients on long- term therapy of diaminopyrimidines?
Blood count
How should we counsel patients taking diaminopyrimidines? (2)
Maintain adequate fluid intake
Seek immediate medical attention if symptoms such as fever, sore throat, rash, mouth ulcers, purpura, bruising or bleeding develop
Why are there restrictions on the use of co- trimoxazole? (2)
drug of choice in the prophylaxis and treatment of penumocytits jivorecci pneumonia
also other indications but need good reason to use
What are examples of tetracyclines? (3)
Tetracycline
Doxycyline
Minocycline
What is the mechanism of action of tetracyclines?
Taken up into bacterial cells
Inhibit protein synthesis
So inhibit cell growth
What are the indications of tetracyclines? (4)
Chlamydia
Rickettsia
Acne
Rosacea
What are the side effects of tetracyclines? (9)
GI disturbances
Antibiotic-associated colitis
Dysphagia
Oesophageal irritation
Hepatotoxicity
Blood disorders
Photosensitivity
Hypersensitivity
Headache and visual disturbances indicate increased intracranial pressure (discontinue treatment)
A patient is taking tetracyclines and complains of headache and visual disturbances. What can this indicate and what must the patient do? (2)
Headache and visual disturbances indicate increased intracranial pressure
Patient should discontinue treatment
What are contraindications of tetracyclines? (3)
Hepatic and renal impairment
Myasthenia gravis: may increase muscle weakness
May exacerbate systemic lupus erythematous
Should tetracyclines be avoided in children under 12?
Yes
Can tetracyclines be given to pregnant/ breast feeding women? (2)
No avoid
As tetracyclines can leave deposition in growing bone and also stain teeth
What things can decrease the absorption of tetracyclines? (7)
Antacids
Aluminium
Calcium
iron
Magensium
Zinc salts
Also milk MAY reduce its absorption too
How should tetracyclines be taken?
The tablets and capsules should be swallowed WHOLE with plenty of fluid while standing or sitting to avoid irritation of the jaw and throat
Which tetracycline should be taken with food?
Doxycycline
When should daptomycin be discontinued?
If patient has unexplained muscular symptoms with significantly elevated creatine kinase
(measure creatinine kinase every 2 days)
Give an example of an oxazolidinone?
Linezolid
What is the mechanism of action of linezolid? (2)
Selectively inhibits bacterial protein synthesis
It is a reversible, non- selective monoamine oxidade inhibitor (MAOI)
What is linezolid active against? (3)
Gram + bacteria
MRSA
vancomycin- resistant cocci
What are indications of linezolid? (2)
Pneumonia
Complicated skin & soft- tissue infections
What are side- effects of linezolid? (6)
Diarrhoea
eosinophilia
headache
GI disturbances
taste disturbances
optic neuropathy
What are contraindications of linezolid? (5)
Confusional states
Bipolar depression
Elderly (increased risk of blood disorders)
History of seizures
Uncontrolled hypertension
What should we monitor in patients taking linezolid?
Monitor full blood count weekly
What should patients taking linezolid avoid eating/ drinking?
Avoid eating large amounts of tyramine- rich foods (such as mature cheese, undistilled alcoholic beverages, and fermented soya bean products).
What medications should linezolid not be given with? (3)
linezolid should not be given with another MAOI
or within 2 weeks of stopping another MAOI
should also be avoided in those recieving SSRIs, 5HT1 agonists (‘triptans’), tricyclic antidepressants, sympathomimetics, dopaminergics, buspirone, pethidine and possibly other opiod analgesics
Linezolid can cause blood disorders. We should closely monitor the full blood count in the following patients:
those who recieve treatment for more than 10- 14 days
have pre- existing myelosuppresion
are recieving drug that may have adverse effects on haemoglobin, blood counts or platelet function
have severe renal impairment
What should be done if significant myelosuppresion occur when taking linezolid?
Treatment should be stopped unless it is considered essential
in which case intensive monitoring of blood counts and appropriate management should be implemented.
What side effect may RARELY occur if linezolid is used for longer than 28 days?
Severe optic neuropathy
To ensure that a patient taking linezolid is not experiencing severe optic neuropathy, what should patients do?
patients should be warned to report symptoms of visual impairment immediately (including blurred vision, visual field defect, changes in visual acuity and colour vision)
What should be done for patients on linezolid experiencing new visual symptoms? (3)
evaluate the patient promptly
and refer to an opthalmologist if necessary
regardless of treatment duration
What should we monitor regularly for patients taking linezolid for longer than 28 days?
visual function
The MANAGEMENT of TB is divided in to two stages. What are these?
Initial phase
Continuous phase
What the is initial phase of treating TB designed to do?
The initial phase is designed to rapidly reduce the population of M . tuberculosis, to minimise bacterial resistance
What four drugs are involved in the treatment of TB in the initial phase? How long are these drugs given for?
The four drugs are: isoniazid, rifampicin, pyrazinamide, ethambutol
The initial phase treatment lasts for two months
What two drugs are involved in the continuous phase? How long are these drugs given for?
Isoniazid and rifampicin
The continious phase treatment lasts for four months
What should we monitor in patients taking anti- tuberculosis drugs? (8)
Drug levels
Visual acuity
Blood counts
hepatic function
renal function
urinalysis
plasma levels
auditory function in elderly
What is nitrofurantoin? (3)
A broad spectrum antibacterial
Active against the majority of urinary pathogens
It is bactericidal in renal tissue and throughout the urinary tract
What are the side effects of nitrofurantoin? (5)
Pulmonary reactions
Nausea and anorexia
Hypersensitivity
Peripheral neuropathy
Blood disorders
What must we monitor in patients taking long- term therapyy of nitrofurantoin (especially in the elderly)? (2)
Hepatic function
Pulmonary function
Nitrofurantoin discolours the urine to?
dark yellow or brown
Before starting nitrofurantoin, a specimen of urine should be collected for culture and sensitivity testing in the following patients: (7)
in men
in pregnant women
in children under 3 years of age
in patients with suspected upper urinary- tract infection, complicated infection or recurrent infection
if resistant organisms are suspected
if urine dipstick testing gives a single positive result for leucocyte esterase or nitrite
if clinical symptoms are not consistent with results of dipstick testing.
(NOTE: treatment should not be delayed while waiting for results)
What type of patients may receive antifungal drugs prophylactically? (2)
immunocompromised patients
as they are at high risk of fungal infections
which antifungal drugs are the choice of drug for fungal infection prophylaxis?
oral triazole antifungals
Out of fluconazole and itraconazole, which one is more reliably absorbed?
fluconazole
Why is a test IV dose of the antifungal drug amphotericin B needed before it is fully given? (3)
as risk of anaphylaxis
patients need test dose and
patients need to be carefully observed for at least 30 minutes after the test dose
(only use prophylactic antipyretics or hydrocortisone in pts who have previously experienced acute adverse reactions)
Are different brands of amphotericin IV interchangeable? (3)
No
prescribers need to specify the brand
as each one varies pharmacodynamics
Who taking itraconazole is at risk of experiencing heart failure? (5)
patients recieving high doses and longer treatment courses
older patients and those with cardiac disease
patients with chronic lung disease associated with pulmonary hypertension
patients recieving treatment with negative inotropic drugs e.g. calcium channel blockers
What is a rare risk of itraconazole? (2)
life threatening hepatotoxicity
discontinue if signs develop
who should itraconazole be avoided in? (2)
avoid or use with caution if history of hepatotoxicity with other drugs or in active liver disease
when should we monitor liver function in patients taking itraconazole? (3)
if treatment continues for longer than one month
if receiving other hepatotoxic drugs
if history of hepatotoxicity with other drugs, or in hepatic impairment
when should patients on itraconazole seek prompt medical attention?
if symptoms such as anorexia, nausea, vomiting, fatigue, abdominal pain or dark urine develop
how should itraconazole be taken?
oral preparations should be taken on an empty stomach
what are side effects of voriconazole? (2)
hepatotoxicity
phototoxicity
in which pts is the side effect: hepatotoxicity of voriconazole increased? what symptoms would require pts to seek immediate medical attention? (2)
risk is increased with haematological malignancy
seek immediate medical attention if symptoms such as: persistent nausea, vomiting, malaise or jaundice
how should pts on voriconazole reduce the risk of the side effect: phototoxicity (4)
to avoid intense or prolonged exposure to direct sunlight
to avoid use of sunbeds
cover skin in sun
sunscreen with high sun protection factor
what should we monitor in pts on voriconazole? (2)
renal function
hepatic function before starting treatments, then at least weekly for 1 month, then monthly during treatment
what should we monitor in patients on ketoconazole? (3)
ECG
Adrenal function can cause adrenal insufficiency i.e fatigue, anorexia, vomiting, hypotension, hyponatraemia, hypoglycaemia
hepatic function
what do signs of liver toxicity include? (6)
severe abdominal pain
dark urine
jaundice
nausea
vomiting
fatigue
what are helminth infections?
most are parasitic worms that infect the large intestine of humans
what are symptoms of threadworm? (4)
itching around the anus and vagina
loss of appetite
weight loss
sleep disturbance
what are symptoms of whipworm? (3)
GI disturbances
colitis
bloody- diarrhoea
What are symptoms of hookworm? (2)
most people dont have any symptoms
severe infections may cause weight loss and anaemia
what are symptoms of roundworm? (3)
high temeprature
dry cough
worm in stools
what is the drug of choice for treating most helminth infections? *2)
mebendazole
(same dose for adults and children over 2)
What measures can be taken to prevent mosquito bites and reduce the risk of mosquito-borne infections? (3)
Prevention is not absolute and ; breakthrough infection can occur.
Personal protection against being bitten is very important.
wear long sleeves and trousers after dusk, using mosquito nets impregnated with permethrin, and using mats and vaporized insecticides.
What is the recommended formulation of Diethyltoluamide (DEET) for adults and children over 2 months of age?
DEET formulations of 20–50% are considered safe and effective when applied to the skin of adults and children over 2 months of age.
How does DEET interact with sunscreen?
DEET reduces the SPF of sunscreen, so a sunscreen of SPF 30-50 should be applied first, followed by the application of DEET.
When should prophylaxis generally be initiated before traveling to an endemic area? (2)
Prophylaxis should generally be started one week before travel into an endemic area.
but does depend on anti- malarial drug
when before travel should mefloquine prophylaxis be started
Mefloquine prophylaxis should be started 2–3 weeks before travel into an endemic area.
How soon before travel should prophylaxis with Malarone® or doxycycline be started?
Prophylaxis with Malarone® or doxycycline should be initiated 1–2 days before travel into an endemic area.
How long should prophylaxis be continued after leaving an endemic area, and are there any exceptions? (2)
Prophylaxis should generally be continued for 4 weeks after leaving an endemic area,
except for Malarone® which should be stopped 1 week after leaving.
What should travelers do if they develop any illness within a year of returning from a malarial region?
Travelers should go immediately to a doctor if they develop any illness.
As any illness within 1 year and especially within 3 months of return from a malarial region might be malaria.
Why are chloroquine and mefloquine considered unsuitable for patients with epilepsy?
due to the risk of neuropsychiatric reactions.
What advice is given for individuals with asplenia regarding malaria prevention?
they are at an increased risk of severe malaria and need to be extra cautious against contracting malaria.
What precautions should be taken for patients with renal impairment regarding malaria prophylaxis?
Proguanil should be avoided, and Malarone® should not be used in patients with EGFR <30.
What advice is given regarding travel to malarious areas for pregnant individuals?
Pregnant individuals are advised to avoid travel to malarious areas.
If taking proguanil, folic acid should be given for the first trimester.
Doxycycline is contraindicated during pregnancy but can be used after 15 weeks’ gestation.
Malarone® should be avoided during pregnancy.
Why do breast-fed infants require prophylaxis against malaria?
as the amounts of antimalarial drugs in breast milk are too variable to provide reliable protection.
What precautions should travelers taking warfarin take regarding chemoprophylaxis? (5)
Travelers taking warfarin should begin chemoprophylaxis 2–3 weeks before departure
Their INR should be stable before departure
and should be measured before starting chemoprophylaxis,
7 days after starting and
7 days after completing the course.
What is the recommended daily dose of Chloroquine (Avloclor) to minimize the risk of ocular toxicity?
4mg/kg daily (or less)
What is the main concern regarding Mefloquine (Lariam) in individuals with a history of psychiatric disorders? (2)
Mefloquine is contraindicated in individuals with a history of psychiatric disorders due to the risk of neuropsychiatric reactions.
These reactions include abnormal dreams, insomnia, anxiety, depression, and, in severe cases, psychosis, suicidal ideation, and suicide.
What should patients do if they experience neuropsychiatric symptoms while taking Mefloquine?
If neuropsychiatric symptoms occur, patients should discontinue Mefloquine immediately and seek immediate medical attention.
It’s important to note that adverse reactions may continue for several months after stopping Mefloquine due to its long half-life.
How might Mefloquine affect a person’s ability to perform skilled tasks like driving?
Mefloquine can cause dizziness or a disturbed sense of balance
, which may affect the performance of skilled tasks like driving. These effects can persist for several months after stopping Mefloquine.
When using Quinine for malaria treatment, which salt forms are doses valid for? (2)
The recommended doses of Quinine for treating malaria apply to specific forms of the drug: quinine hydrochloride, quinine dihydrochloride, and quinine sulfate.
However, these doses do not apply to quinine bisulfate.
What drugs are commonly used to treat herpesvirus infections? (3)
aciclovir
famciclovir
valaciclovi
What is the typical treatment approach for herpes simplex infections? (3)
Treatment for herpes simplex infections should start as early as possible, usually within 5 days of the appearance of the infection.
Mild superficial infections are treated with topical antiviral drugs like aciclovir cream
while more severe infections and genital herpes require treatment with systemic antiviral drugs such as aciclovir tablets.
How should neonates with varicella-zoster (chickenpox virus) infections be treated?
Neonates with varicella-zoster infections should be treated with parenteral antiviral to reduce the risk of severe disease.
(However, in healthy children between 1 month and 12 years, antiviral treatment is usually not required unless the disease is severe)
What is the recommended timing for initiating and continuing antiviral treatment in herpes zoster (shingles) infections? (2)
In herpes zoster infections, systemic antiviral treatment should be started within 72 hours of the onset of rash
and is usually continued for 7–10 days.
What is the main goal of treatment for HIV infection? What drugs is this achieved through? (2)
The main aim of treatment for HIV infection is to prevent mortality and morbidity while minimizing drug toxicity and reducing the risk of HIV transmission to sexual partners.
This is achieved through a combination of drugs known as ‘highly active antiretroviral therapy’, which includes drugs like zidovudine, abacavir, didanosine, lamivudine, and tenofovir.
What drugs are effective for reducing the replication of influenza A and B viruses? When are they most effective? (2)
Oseltamivir and zanamivir are effective for reducing the replication of influenza A and B viruses. They are most effective when started within a few hours of the onset of symptoms.
What are the symptoms of Varicella Zoster (chicken pox)? (2)
Varicella Zoster (chicken pox) presents with a red rash and itchy spots that turn into fluid-filled blisters after 12 hours.
These blisters will crust over after a week.
Describe the symptoms of Herpes Zoster (shingles).
Herpes Zoster (shingles) typically begins with pain, followed by a tingling or numb rash that develops into itchy blisters, similar in appearance to chickenpox.
What are the symptoms of Herpes simplex (cold sores)?
Herpes simplex (cold sores) is characterized by a tingling, itching, or burning sensation around the mouth, followed by the appearance of small fluid-filled sores.
Describe the symptoms of Impetigo.
Impetigo presents with red sores that quickly burst, leaving behind thick, golden crusts, typically around 2cm across.
What are the symptoms of Hand, foot and mouth disease?
Hand, foot, and mouth disease is characterized by mouth ulcers appearing after one or two days, followed by a rash made up of small, raised red spots on the skin. These spots may turn into small grey blisters.
Describe the appearance of Molluscum contagiosum.
Molluscum contagiosum presents as small, firm, raised, flesh-colored spots on the skin, with a thick yellowish-white substance released if the spots are popped.
What are the symptoms of Scarlet fever?(6)
sore throat
headache
swollen glands
red rash that feels like sandpaper
red cheeks
white or red tongue.
What are the symptoms of Slapped cheek syndrome?
Slapped cheek syndrome presents with a bright red rash on the cheeks, temperature, sore throat, runny nose, and headache.
How do Verrucas typically appear?
Verrucas appear on the soles of the feet as white with a black dot in the center, and they are flat rather than raised.
Describe the appearance of Warts.
Warts are typically round or oval-shaped, firm, and raised
Which herpes simplex virus (HSV) is generally associated with infections of the mouth and lips, as well as the eye?
Herpes simplex virus type 1 (HSV-1)
What types of herpes simplex virus (HSV) are most often associated with genital infections?
Genital infections are most often associated with both herpes simplex virus type 1 (HSV-1) and herpes simplex virus type 2 (HSV-2).
What are some general signs and symptoms of infections?
General signs and symptoms of infections include fever, malaise, and aches and pains.
What localized signs and symptoms might indicate an infection?
Localized signs and symptoms of infections include the presence of pus, swelling, and inflammation at the site of infection.
How might infections manifest differently based on age? (2)
drowsiness in children
confusion in the elderly
What clinical markers might indicate an infection with a focus on the renal system?
worsening renal function.
What vital signs might be indicative of an infection? (2)
low blood pressure
raised blood glucose levels
Which lab values could suggest the presence of an infection? (5)
high erythrocyte sedimentation rate (ESR
high C-reactive protein levels
elevated temperature
increased respiratory rate
elevated pulse rate.
What is the mechanism of action of Chloramphenicol?
Chloramphenicol inhibits protein synthesis.
What is the spectrum of activity of Chloramphenicol?
Chloramphenicol has a broad-spectrum of activity.
How does Chloramphenicol typically act on bacteria?
Chloramphenicol exerts a bacteriostatic effect, meaning it inhibits the growth of bacteria.
What are the risks associated with Chloramphenicol use? Who should it be avoided in? (2)
The risks associated with Chloramphenicol use include blood dyscrasias and Grey Baby Syndrome.
It should be avoided in pregnant women.
Which tetracyclines are photosensitive so pts need to avoid excessive light? (2)
Demeclocycline
Doxycycline
(DD)
With which tetracyclines should milk be avoided? (3)
Demeclocycline
Oxytetracycline
Tetracycline
(DOT)
Which tetracyclines can cause oesophageal irritation and thus need to be swallowed whole? (3)
Doxycycline (capsules)
Minocycline (tabs/ caps)
Tetracycline (tabs)
(DMT)
Which anti- TB drugs have side effect: liver toxicity? (3)
Isoniazid
rifampicin
pyrazinamide
Which anti- TB drug has side effect: peripheral neuropathy? (1)
Isoniazid
Which anti- TB drug has side effect: ocular toxicity
ethambutol
Describe the symptoms of Scabies.
Scabies is characterized by intense itching, a rash with tiny red spots, and burrow marks that appear as wavy, silver-colored lines on the skin.
What are the symptoms of Mumps?
Mumps is characterized by swollen salivary glands, fever, headache, and joint pain.
What are the symptoms of Tinea corporis (ringworm)?
Tinea corporis (ringworm) affects the arms and legs, presenting as round, red, or silvery patches of skin that may be scaly, inflamed, and itchy.
What are the symptoms of Measles/Rubella?
Measles/Rubella presents with cold-like symptoms and a red-brown blotchy rash that lasts for 3 days.
What is the presentation of Tinea cruris?
Tinea cruris manifests as a fungal groin infection, characterized by itchy inflammation with a visible patch of dry scaly skin.
Out of fluconazole and itraconazole which one is preferred in patients at risk of invasive aspergillosis?
itraconazole