Microbiology Tutorial

Question 1

what causes most throat infections

Answer 1

viruses

Question 2

what throat infection can have serious complications

Answer 2

strep A (strep pyogenes)

Question 3

what is this:
six-month-old baby to your GP surgery first thing one morning because the baby
has been awake since 2 a.m. screaming with pain and refusing to sleep. He has had a cold for 2 days
and seemed to have a raised temperature last night. The baby had finally fallen asleep at 7 a.m.,
exhausted, and when his mum picked him up to come to the surgery, she noticed some green
discharge on the pillow that appeared to have come from his right ear. You examine the baby and
see that his right ear canal is full of pus and that it is difficult to visualise the right tympanic
membrane

Answer 3

acute otitis media

Question 4

what organisms commonly cause AOM

Answer 4

strep pneumoniae, haemophilus influenzae, moraxella catarrhalis, group A strep

Question 5

what is the treatment for children with AOM

Answer 5

oral amoxicillin (not ear drops) (also not penicillin as has better oral absorption)

Question 6

whats more broad range penicillin or amoxicillin

Answer 6

amoxicillin- also covers e.g. H influenzae

Question 7

what are the characteristics of strep pneumoniae

Answer 7

diplococci (cocci in pairs)

gram +ve

Question 8

will giving amoxicillin in mono give you a macular rash

Answer 8

mooka says no
dr says yes
probs mo

Question 9

what virus causes infective mononucleosis

Answer 9

ebstein barr virus

Question 10

what are the tests for mono

Answer 10

EBV IgM, heterophile antibody, blood count and film, LFTs, paul-bunnell and monospot

Question 11

swimmer with ear pain, patches of black/grey wax - what is this

Answer 11

acute otitis media caused by aspergillus niger

Question 12

what causes a fungal external ear infection

Answer 12

fungal spore are in the air, need moist ears to cause infection

Question 13

what is the treatment for a fungal acute otitis externa

Answer 13

aural toilet

topical clotrimazole

Question 14

name two organisms that commonly cause acute otitis externa

Answer 14

s. aureus, pseudomonas

Question 15

what pathogen causes malignant otitis externa

Answer 15

pseudomonas

Question 16

what type of bacteria is pseudomonas

Answer 16

gram -ve bacillus

Question 17

can fungal ear infections become invasive

Answer 17

no

Question 18

what are centor criteria for tonsilitis

Answer 18

fever 
inflamed tonsils 
no cough 
cervical lymphadenopathy
tonsilar swelling or exudate 

(add 1 if <15, -1 over 44)

Question 19

what antibiotics for tonsilitis

Answer 19

penicillin

Question 20

what is the treatment for a peritonsilar abscess

Answer 20

drainage and IV antibiotics

Question 21

what are possible complications of tonsilitis

Answer 21

rheumatic fever, glomerulonephritis, peritonsilar abscess

Question 22

what does this patient have:
A two year old boy was taken to his GP with the complaint of difficulty in eating for a day. The
patient had developed fever suddenly the previous night without any systemic ‘flu-like symptoms.
After 12 hours his mother had noticed two papules; one in the palm and one in the foot. Following
that he developed a severe ache in legs and difficulty eating. The patient experienced a severe
itching over the papules.
On examination, the patient was febrile and had a body temperature of 39°C. Many papules were
noted on the palm and foot. 2-3 papules were present over the trunk region and knee as well
(Figure). Intraoral examination revealed multiple reddish macules, measuring approximately 2mm in
diameter in the roof of the hard palate. No other lesions were present intra-orally.

Answer 22

hand, foot and mouth disease

Question 23

what is the management for hand foot and mouth disease

Answer 23

fluids, paracetamol syrup for fever, topical local anaesthetic for intraoral application, antihistamine syrup and calamine solution for itching

Question 24

what happens to the papules in hand foot and mouth disease

Answer 24

turn into fluid filled blisters
palatal lesions should subside allowing swallowing problems to resolve
vesicles start to form crustations

Question 25

what causes hand food and mouth disease

Answer 25

coxsackie (enterovirus)

Question 26

what minimises your change of contracting hand food and mouth

Answer 26

good hygiene, wash hands

Question 27

what are the side efffects of quinolones

Answer 27

tendonitis, seizures, c. diff, gi problems, hearing and taste problems etc

Question 28

what antibiotics cause c. diff

Answer 28

fluoroquinolones, cephalosporins, penicillins and clindamycin