Microbiology

Question 1

What are some causes of cold sores?

Answer 1

Reactivation from nerves causing active infection

Various stimuli

Acliclovir therapy or suppression

Question 2

What is a major complication of the Herpes simplex virus ?

Answer 2

Herpes simplex encephalitis

Question 3

How is a diagnosis of Herpes Simplex virus confirmed?

Answer 3

Swab lesion of virus transport medium

Detection of viral DNA by PCR

Question 4

Which virus causes Herpangina?

Answer 4

Coxsackie viruses

Question 5

How does Herpangina present?

Answer 5

Vesicles/ulcerd on soft palate

Question 6

Which virus causes hand foot and mouth disease?

Answer 6

Cocsackie viruses

Question 7

How does Behcet’s disease ulcers present?

Answer 7

Recurrent oral ulcers
Genital ulcers
Uveitis

Question 8

Which scoring system is used to predict the likelihood of GRiup A Strep infection?

Answer 8

Fever PAIN criteria

Question 9

What is the name if the bacteria that causes diptheria?

Answer 9

Corynebacterium diptheriae

Question 10

How does diptheria present?

Answer 10

Severe sore throar with a grey white membrane across the pharynx.
The organism produces a potent exotoxin which is cardiotoxic and neurotoxic.

Question 11

What is the treatment for diptheria?

Answer 11

Antitoxin and supportive

Penicillin/Erythromycin

Question 12

What are the clinical features of glandular fever?

Answer 12

Fever

Enlarged lymoh nodes

Sore throat, pharyngitis, tonsillitis

Malaise, lethargy

Jaundice, hepatitis (complications)

Question 13

What is the laboratory confirmation of Epstein Barr virus?

Answer 13

Epstein Barr virus IgM

Heterophile antibody

• Paul Bunnell test
• Monospot test

Blood count and film

Liver function test

Question 14

How does thrush present?

Answer 14

White patches on red, raw mucous membranes in throat/mouth

Question 15

What is are some causes of thrush?

Answer 15

Post-antibiotics
Immunosuppressed patients
Smokers
Inhaled steroids

Question 16

How is thrush treated?

Answer 16

Nystatin (1ml 4x daily for 7 days)

OR

Fluconazole (50mg/day for 7 days)

Question 17

What is otitis media?

Answer 17

An upper respiratory infection involving the middle ear by extension of infection up the Eustachian tube.

Predominantly disease of infants and children

Question 18

What are the most common bacteria that cause otitis media?

Answer 18

Hameophilus influenzae

Streptococcus pneumoniae

Streptococcus pyogens

Question 19

How is otitis media diagnosed?

Answer 19

By swab of pus if eardrum perforates

Question 20

What is the treatment for otitis media?

Answer 20

80% resolve in 4 days without antibiotics

First line - amoxicillin (5 days)

Second line - erythromycin (5 days)

Question 21

What is otitis externa?

Answer 21

Inflammation of the outer ear canal

Question 22

What is the clinical presentation of otitis externa?

Answer 22

Redness and swelling of the skin of the ear canal

May be itchy

Can become sore and painful

May be discharge or increased amounts of ear wax

Hearing can be affected if canal becomes blocked by swelling or secretions

Question 23

What are some common bacterial causes of otitis externa?

Answer 23

Staphylococcus aureus

Proteus sp.

Pseudomonas aerguinosa

Question 24

What are some fungal causes of otitis externa?

Answer 24

Aspergillus niger

Candida albicans

Question 25

How is otitis externa managed?

Answer 25

Topical aural toilet Swab to microbiology and prescription of antimicrobial reserved for unrepsonsive/severe cases Treat depending on culture results - Topical clotrimazole (Canesten) - Topical Nystatin - Gentamicin 0.3% drops

Question 26

What is malignant otitis?

Answer 26

An extension of otitis externa into the bone surrounding the ear canal

Question 27

What are some symptoms of malignant otitis?

Answer 27

Pain and headache

Question 28

What are signs of malignant otitis?

Answer 28

Granulation tissue at bone - cartilage junction of ear canal Exposed bone in the ear canal Facial nerve palsy (drooping face on the side of lesion)

Question 29

Which investigations are done for malingnant otitis?

Answer 29

Plasma viscosity/CRP Radiological imaging Biopsy and culture to demonstrate the extent of the osteitis and its cause

Question 30

What are some risk factors for malignant otitis?

Answer 30

Diabetes and radiotherapy to head and neck

Question 31

What is acute sinusitis?

Answer 31

Mild discomfort over frontal or maxillary sinuses due to congestion seen in patients with upoer respiratory viral infections. Severe pain and tenderness with purulent nasal discharge indicates secondary bacterial infection

Question 32

What is the treatment of acute sinusitis?

Answer 32

Antibiotics for severe cases of > 10 days duration First line - Phenoxymethylpencillin Second line - Doxycycline ( NOT FOR USE IN CHILDREN!!!)

Question 33

Which antibiotics are used in ear drops for a bacterial infection?

Answer 33

Neomycin Gentamicin Polymyxin B Framycetin

Question 34

Why are antibiotic ear drops not used in eczematous otitis externa?

Answer 34

They may cause local sensitivity.

Question 35

Which types of ear drops should be used as wax solvents?

Answer 35

Sodium bicarbonate Olive oil Almond oil

Question 36

What are some side effects of ear drops?

Answer 36

Dizziness Local sensitivity Ototoxicity

Question 37

How can ear drops cause dizziness?

Answer 37

If the drops are not close to body temperature.