microbiology

Question 1

What is the first line abx for c.diff infection without sepsis? What is second line abx?

Answer 1

Oral vancomycin is the first line treatment option for C. difficile. A 10-day course is recommended. Intravenous metronidazole would be added if there was a life-threatening infection
Oral fidaxomicin is a second line therapy for C difficile infection. It may also be used for recurrent C. difficile cases.

Question 2

What abx are used in pregnancy for UTI? how long?

Answer 2

first-line: nitrofurantoin (should be avoided in third trimester)
second-line: amoxicillin or cefalexin

Need 7 day course

Question 3

What is first line abx for meningitis and what do you add in if elderly/ immunocomp?

Answer 3

IV cefotaxime (first line)

IV amoxicillin is reserved for scenarios where there is suspicion of Listeria monocytogenes

Question 4

First line abx for non-dessimated lyme diseae and length of course? Second line? In dessimated disease?

Answer 4

First line treatment of non-disseminated Lyme disease is a 21 day course of oral doxycycline,

Amoxicillin is 2 nd line

Ceftriaxone is used in disseminated disease.

Treatment should be started based on clinical suspicion as serology can take 3-8 weeks to become positive.

Question 5

What is the most common cause of bronchiectasis exacerbations?

Answer 5

Haemophilus influenzae

Question 6

What are the features of discitis? What is the most common causitive agent?

Answer 6

back pain
fever/ gen unwell
neurological features

Most common agent is bacterial (S.aureus)

Question 7

What is used as prophylaxis for contacts of patients with meningococcal meningitis?

Answer 7

Oral ciprofloxacin or rifampicin

Question 8

How do you treat latent TB? What is it?

Answer 8

Latent TB - asymptomatic and non-infectious. Have a positive tuberculin skin test/ Interferon-Gamma Release Assay (IGRA) combined with a normal CXR

3 months of isoniazid (with pyridoxine) and rifampicin, or
6 months of isoniazid (with pyridoxine)

Question 9

1st line vs 2nd line abx for lyme disease?

Answer 9

1st line - doxycycline
2nd line - amoxicillin

Question 10

management of Campylobacter jejuni?

Answer 10

usually self-limiting
the BNF advises treatment if severe or the patient is immunocompromised eg high fever, bloody diarrhoea, >8 stools a day or sx lasted >7 days
1st line = clarithromycin

Question 11

What are the most common micro organisms responsible for otitis media?

Answer 11

Streptococcus pneumonaie, Haemophilus influenzae and Moraxella catarrhalis