infections 🦠

Question 1

What is the antibacterial spectrum of aminoglycosides?

Answer 1

Bactericidal against some Gram positive and many Gram negative organisms

Question 2

Why are aminoglycosides not given orally?

Answer 2

They are not absorbed from the gut; risk of absorption increases in IBD and liver failure.

Question 3

When should serum concentration be closely monitored in IV aminoglycoside therapy?

Answer 3

In obese patients

Question 4

What are the peak and trough levels for gentamicin in multiple daily dosing?

Answer 4

Peak: 5 to 10 mg/L (general)

Question 5

How should dosing be adjusted if trough or peak levels are high?

Answer 5

Trough too high: increase interval. Peak too high: decrease dose.

Question 6

What conditions require both dose and interval adjustments in aminoglycoside use?

Answer 6

Severe renal impairment.

Question 7

Which drugs should be avoided with aminoglycosides due to ototoxicity?

Answer 7

Cisplatin

Question 8

Which drugs increase the risk of nephrotoxicity when combined with aminoglycosides?

Answer 8

NSAIDs

Question 9

What are key contraindications for aminoglycosides?

Answer 9

Myasthenia gravis and pregnancy (risk of fetal auditory damage).

Question 10

When should once-daily high-dose aminoglycosides be avoided?

Answer 10

In endocarditis, HACEK endocarditis, burns >20%, or CrCl <20 mL/min.

Question 11

What infections are treated with cephalosporins?

Answer 11

Septicaemia

Question 12

Which cephalosporins are used for CNS infections like meningitis?

Answer 12

Cefotaxime and ceftriaxone.

Question 13

Name one oral cephalosporin from the third generation.

Answer 13

Cefixime.

Question 14

What is the main side effect of cephalosporins and who should avoid them?

Answer 14

Hypersensitivity; avoid in patients with penicillin allergy due to cross

Question 15

When is chloramphenicol typically used and what is its major pregnancy risk?

Answer 15

Eye infections; avoid in third trimester due to risk of grey baby syndrome.

Question 16

What is the OTC age limit for chloramphenicol eye drops?

Answer 16

2 years and older.

Question 17

What is the major risk associated with clindamycin use?

Answer 17

Antibiotic associated colitis

Question 18

What action should be taken if C. difficile is suspected while on clindamycin?

Answer 18

Discontinue immediately and seek specialist advice.

Question 19

How is vancomycin (glycopeptides) administered for systemic infections?

Answer 19

Parenterally (IV) due to poor oral absorption.

Question 20

What is the target trough concentration for vancomycin?

Answer 20

15 to 20 mg/L.

Question 21

What are the major side effects of vancomycin?

Answer 21

Red man syndrome

Question 22

What is the antibacterial spectrum of macrolides?

Answer 22

Bacteriostatic

Question 23

What are common side effects of macrolides?

Answer 23

GI upset

Question 24

Which macrolide has the least effect on CYP3A4?

Answer 24

Azithromycin.

Question 25

What drug interactions are notable with macrolides?

Answer 25

Increased risk of QT prolongation with other QT

Question 26

What is metronidazole effective against?

Answer 26

Anaerobes and protozoa.

Question 27

What important counselling point must be given with metronidazole?

Answer 27

Avoid alcohol during and for 48 hours after treatment due to disulfiram

Question 28

What are side effects of metronidazole?

Answer 28

Metallic taste

Question 29

What is nitrofurantoin used to treat?

Answer 29

Lower urinary tract infections (UTIs).

Question 30

What are key contraindications for nitrofurantoin?

Answer 30

Renal impairment (CrCl <45 mL/min)

Question 31

What side effects are associated with nitrofurantoin?

Answer 31

Pulmonary reactions (acute and chronic)

Question 32

What bacteria are quinolones effective against?

Answer 32

Broad

Question 33

What are the key risks associated with quinolones?

Answer 33

Tendon rupture (especially in elderly)

Question 34

What interactions are notable with quinolones?

Answer 34

Antacids

Question 35

Why are quinolones restricted in the UK?

Answer 35

Due to serious and potentially irreversible side effects.

Question 36

What is the risk with linezolid treatment over 28 days?

Answer 36

Severe optic neuropathy; visual monitoring is essential.

Question 37

What monitoring is required if linezolid is used for more than 10–14 days?

Answer 37

Weekly full blood count (FBC) due to risk of blood disorders.

Question 38

Which interactions make serotonin syndrome a concern with linezolid?

Answer 38

SSRIs

Question 39

Who can benefit from macrolides as an alternative?

Answer 39

Patients allergic to penicillin.

Question 40

What are key indications for macrolides?

Answer 40

Respiratory infections

Question 41

Which macrolide is preferred in pregnancy?

Answer 41

Erythromycin

Question 42

Key side effects of macrolides?

Answer 42

Hepatotoxicity

Question 43

Important macrolide interactions?

Answer 43

CYP inhibitors (↑ statin

Question 44

What are key side effects of metronidazole?

Answer 44

Metallic taste

Question 45

Why should alcohol be avoided with metronidazole?

Answer 45

Causes disulfiram

Question 46

When should nitrofurantoin be avoided?

Answer 46

At term in pregnancy and if eGFR <45 mL/min.

Question 47

What are common side effects of nitrofurantoin?

Answer 47

Pulmonary and hepatic toxicity

Question 48

Administration advice for nitrofurantoin?

Answer 48

Take with food.

Question 49

What causes maculopapular rash in glandular fever patients?

Answer 49

Amoxicillin or ampicillin.

Question 50

Which penicillin is stable orally?

Answer 50

Penicillin V (phenoxymethylpenicillin).

Question 51

What are the risks with flucloxacillin?

Answer 51

Hepatitis and cholestatic jaundice

Question 52

What are antipseudomonal penicillins and how are they administered?

Answer 52

Piperacillin (with tazobactam)

Question 53

What is the serious risk of intrathecal penicillin administration?

Answer 53

Encephalopathy (fatal).

Question 54

Name 5 examples of quinolones

Answer 54

Ciprofloxacin

Question 55

What major CNS and psychiatric risks do quinolones pose?

Answer 55

Seizures

Question 56

Key serious adverse effects of quinolones?

Answer 56

Tendonitis

Question 57

Who should avoid quinolones?

Answer 57

Epileptics

Question 58

What should be avoided when taking quinolones?

Answer 58

Dairy

Question 59

What is the “does like milk” exception for taking with dairy with tetracyclines?

Answer 59

Doxycycline

Question 60

Key side effects of tetracyclines?

Answer 60

Teeth discolouration (avoid <12 years and pregnancy)

Question 61

Administration advice for tetracyclines?

Answer 61

Avoid sunlight; take with a full glass of water sitting upright.

Question 62

What are the major risks with long term trimethoprim use?

Answer 62

Blood dyscrasias (e.g. agranulocytosis); monitor for fever

Question 63

Why is trimethoprim contraindicated in pregnancy?

Answer 63

It's an antifolate and teratogenic in the 1st trimester.

Question 64

Which important drug interactions should be considered with trimethoprim?

Answer 64

Methotrexate and phenytoin (increased toxicity risk).

Question 65

What electrolyte abnormality can trimethoprim cause?

Answer 65

Hyperkalaemia

Question 66

What is the first line treatment for active TB?

Answer 66

RIPE regimen: Rifampicin

Question 67

What is the continuation phase of TB treatment?

Answer 67

Rifampicin and Isoniazid for 4 months.

Question 68

What is given with isoniazid to prevent neuropathy?

Answer 68

Pyridoxine (vitamin B6).

Question 69

What are key side effects of TB drugs?

Answer 69

Rifampicin: red/orange body fluids CYP450 inducer Isoniazid: peripheral neuropathy CYP450 inhibitor. Pyrazinamide: hepatotoxic. Ethambutol: visual toxicity.

Question 70

How is latent TB treated?

Answer 70

Rifampicin + isoniazid for 3 months OR isoniazid for 6 months.

Question 71

What should be monitored in patients aged 35–65 with latent TB?

Answer 71

Hepatotoxicity.

Question 72

What are essential bite prevention strategies in malaria?

Answer 72

DEET (20 to 50%)

Question 73

Is DEET safe in pregnancy and breastfeeding?

Answer 73

Yes

Question 74

Which patients are at higher malaria risk?

Answer 74

Asplenic patients

Question 75

Which antimalarials are safe in pregnancy?

Answer 75

Chloroquine and proguanil (+5 mg folic acid).

Question 76

What is the guidance for warfarin patients taking antimalarials?

Answer 76

Start 2 to 3 weeks before departure; monitor INR before

Question 77

What is first line for aspergillosis and cryptococcosis (fungal infections)?

Answer 77

Cryptococcosis: Amphotericin B.

Question 78

What causes vaginal and oral thrush

Answer 78

and what are resistant treatments?

Question 79

What are serious side effects of systemic antifungals (azoles)?

Answer 79

QT prolongation

Question 80

What precautions are needed with amphotericin B?

Answer 80

Risk of renal failure

Question 81

Which antivirals treat herpes zoster and varicella?

Answer 81

Aciclovir

Question 82

What is the presentation of shingles?

Answer 82

Onesided rash with tingling/itching in a dermatomal pattern.

Question 83

When should antivirals be started in chickenpox?

Answer 83

Within 24 hours of rash onset in those over 14 years.

Question 84

List treatments for COVID-19?

Answer 84

Oxygen (various levels)

Question 85

What vaccines are available for COVID-19?

Answer 85

Spikevax (Moderna)

Question 86

What is a rare adverse effect of the AZ vaccine?

Answer 86

Thrombocytopenia and thrombosis.

Question 87

What is the goal of HIV therapy?

Answer 87

Reduce viral load to undetectable levels.

Question 88

What is standard HIV therapy?

Answer 88

Triple therapy: NRTIs + NNRTIs or PIs or INIs.

Question 89

What is post-exposure prophylaxis (PEP) for HIV?

Answer 89

Start within 72 hours

Question 90

What is pre-exposure prophylaxis (PrEP)?

Answer 90

Long-term therapy for individuals at high risk.