Microbiology

Question 1

Staph Aureus Bacteremia Mx

Answer 1

1. High dose fluclox (2g IV) for 2weeks
2. Vancomycin if high risk of MRSA

Question 2

Amoebiasis (?Aetiology)

Answer 2

Organism: Entamoeba Histolytica
Spread: Faecal-oral route
Can cause liver/colonic abscesses

Question 3

Amoebic dysentery

Answer 3

Profuse, bloody diarrhoea
Long incubation period
Stool microscopy -> Trophozoites
Treatment -> Oral metronidazole + Diloxanide (luminal agent)

Question 4

Amoebic liver abscess (Features)

Answer 4

Fever
RUQ pain
Systemic symptoms (malaise)
Hepatomegaly

Question 5

Amoebic liver abscess (Ix + Mx)

Answer 5

Ix: Ultrasound + Serology
Mx: Oral metronidazole + luminal agent

Question 6

Dengue fever (Aetiology)

Answer 6

RNA virus (Flavivrus)
Vector: Aedes aegypti mosquito
Incubation period of 7 days

Question 7

Dengue fever (Features - non severe)

Answer 7

Fever
Headache
Myalgia/arthralgia
Facial flushing
Maculopapular rash

Question 8

Dengue fever (warning signs)

Answer 8

Abdominal pain
Hepatomegaly
Persistent vomiting
Clinical fluid accumulation (Ascites/pleural effusion)

Question 9

Severe dengue fever (Haemorrhagic fever)

Answer 9

Form of DIC
- Thrombocytopenia + spontaneous bleeding
Around 20-30% go on to develop dengue shock syndrome

Question 10

Dengue (Ix + Mx)

Answer 10

Bloods: Leukopenia, throbmocytopenia, raised aminotransferases
Diagnostic:
- Serology
- NAAT for viral RNA
- NS1 antigen test
Mx: Symptomatic