microbiology

Question 1

what are the features of herpes simplex virus 1?

Answer 1

Type 1 acquired in childhood
HSV1 is cause of oral lesions
70% UK adults have been infected
Transmitted via infected oral secretions during close contact
Frequently asymptomatic
Clinical manifestations varies

Question 2

what are the features of primary gingivostomatitis?

Answer 2

caused by HSV1
Disease of pre-school children
Primary infection
Systemic upset
affects Lips, buccal mucosa, hard palate
Vesicles 1-2mm
Ulcers

Question 3

how is primary gingivostomatitis treated?

Answer 3

aciclovir

Question 4

is herpes forever?

Answer 4

yes

Question 5

what are the features of herpes cold sores?

Answer 5

Reactivation from nerves causes active infection
Various stimuli
Aciclovir therapy or suppression
Not all reactivations are symptomatic
Aciclovir does not prevent latency

Question 6

name a complication of HSV?

Answer 6

encephalopathy leading to temporal lobe necrosis

Question 7

how is HSV confirmed?

Answer 7

swab lesion then detection of viral DNA by PCR

Question 8

which virus causes herpangina?

Answer 8

coxsackie virus

Question 9

what are the features of herpangina?

Answer 9

Vesicles/ulcers on soft palate
Similar patient age range to 1ry HSV gingivostomatitis

Question 10

how is herpangina diagnosed?

Answer 10

clinically or PCR

Question 11

what causes hand, foot and mouth disease?

Answer 11

coxsackie virus

Question 12

what is an alternative kind of mouth ulcer?

Answer 12

apthous ulcer

Question 13

what are the features of an apthous ulcer?

Answer 13

non-viral and self limiting
recurring and painful
confined to mouth
no systemic disease
begin in childhood, usually go by 30s
each ulcer lasts less than 3 weeks

Question 14

what are some recurrent ulcers associated with systemic disease?

Answer 14

Behcets disease
IBS
reiters disease
skin disease

Question 15

what are the features of behcets disease?

Answer 15

Recurrent oral ulcers
Genital ulcers
Uveitis.
It can also involve visceral organs such as the gastrointestinal tract, pulmonary, musculoskeletal, cardiovascular and neurological systems
Commonest in Middle East and Asia

Question 16

what is the clinical pres of a sore throat?

Answer 16

pain at the back of mouth

Question 17

what is the clinical pres of acute pharyngitis?

Answer 17

inflammation of the part of the throat behind the soft palate (oropharynx)

Question 18

what is the clinical pres of tonsilitis?

Answer 18

inflammation of the tonsils

Question 19

which scores are used to determine if abx should be prescribed in a sore throat?

Answer 19

feverPAIN and Centor clinical prediction

Question 20

which disease should be considered if sore throat and lethargy persist in patient aged 15-25?

Answer 20

glandular fever (EBV)

Question 21

what are some complications of tonsilitis and pharyngitis?

Answer 21

Otitis media (most common)
Peritonsillar abscess (quinsy)
Parapharyngeal abscess
Lemierre Syndrome (Suppurative thrombophlebitis of jugular

Question 22

when should there be an imediate referral in sore throat?

Answer 22

Stridor, breathing difficulty, clinical dehydration, systemically unwell

Question 23

how should a sore throat be managed?

Answer 23

Self Care advice: giving simple advice
Prescribing antibiotics ONLY where appropriate
Identify and manage immunosuppressed people
Identifying those who need admission/referral
-Throat cancer is suspected (persistent sore throat,
especially if there is a neck mass)
-Sore or painful throat lasts for 3 to 4 weeks. There is
pain on swallowing or dysphagia for more than 3
weeks
-Red, or red and white patches, or ulceration or
swelling of the oral/pharyngeal mucosa persists for
more than 3 weeks
-Stridor / respiratory difficulty is an emergency

Question 24

which pathogen commonly causes a bacterial sore throat?

Answer 24

strep pyogenes (group A strep)

Question 25

how is strep pyogenes treated?

Answer 25

penicillin

Question 26

what type of bacteria is strep pyogenes?

Answer 26

gram positive cocci chains
beta-haemolysis (complete)

Question 27

what are some late complications of strep pyogenes?

Answer 27

Rheumatic fever
-3 weeks post sore throat
-fever, arthritis and pancarditis
Glomerulonephritis
-1-3 weeks post sore throat
-haematuria, albuminuria and oedema

Question 28

which drugs can cause neutropenia?

Answer 28

carbimazole

Question 29

who is at risk of neutropenia?

Answer 29

people with chemotherapy, known/suspected leukaemia, asplenia, aplastic anaemia or HIV with low CD4, or on an immunosuppressant

Question 30

how is neutropenia confirmed?

Answer 30

urgent FBC and withhold drug until results are available
seek imediate specialist advice

Question 31

if feverPAIN score is 4/5 which drug should be considered?

Answer 31

phenoxymethylpenicillin

Question 32

what happens to the throat in a diptheria infection?

Answer 32

the pseudomembrane in the posterior pharynx can become very large and may obstruct airway

Question 33

how is diphtheria diagnosed?

Answer 33

a sample of the resp tract secretions

Question 34

how is diphtheria treated?

Answer 34

antitoxin and supportive
penicillin/erythromycin

Question 35

what are the symptoms of infectious mononucleosis (glandular fever)

Answer 35

Disease of young adults
Fever
Enlarged lymph nodes
Sore throat, pharyngitis, tonsillitis
Malaise, lethargy
Jaundice/hepatitis
Rash
Haematology
Leucocytosis (lymphocytosis)
Presence of atypical lymphocytes in blood film
Splenomegaly
Palatal petechiae

Question 36

what are the complications of infectious mononucleosis?

Answer 36

Protracted but self limiting illness
Anaemia, thrombocytopenia
Splenic rupture
Upper airway obstruction
Increased risk of lymphoma, especially in immunosuppressed.

Question 37

what is the clincical pres of candida albicans (thrush)

Answer 37

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

Question 38

what can cause candida albicans?

Answer 38

endogenous (post antibiotics, immunosuppressed, smokers, inhaled steroids)

Question 39

what is the treatment for candida albicans?

Answer 39

nystatin or fluconazole

Question 40

what is acute otitis media?

Answer 40

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

Predominantly disease of infants and children

Presents with earache

Question 41

what is an infection of the middle ear

Answer 41

usually viral with a secondary bacterial infection

Question 42

which bacteria usually causes a middle ear infection?

Answer 42

Haemophilus influenzae, Streptococcus pneumoniae and Streptococcus pyogenes.

Question 43

how is a middle ear infection diagnosed?

Answer 43

– swab of pus if eardrum perforates

Question 44

how is a middle ear infection treated?

Answer 44

80% resolve in 4 days with no abx
first line- amox
second line- arythromycin

Question 45

what is otitis externa?

Answer 45

inflammation of the outer ear canal

Question 46

what are the clinical features of otitis externa?

Answer 46

Redness and swelling of the skin of the ear canal
It may be itchy (especially in the early stages)
Can become sore and painful
There may be a discharge, or increased amounts of ear wax
If the canal becomes blocked by swelling or secretions, hearing can be affected

Question 47

what are the bacterial causes of otitis externa?

Answer 47

Staphylococcus aureus
Proteus spp
Pseudomonas aeruginosa

Question 48

what are the fungal causes of otitis externa?

Answer 48

Aspergillus niger
Candida albicans

Question 49

how is otitis externa managed?

Answer 49

Topical aural toilet
Swab to microbiology and prescription of antimicrobial reserved for unresponsive or severe cases
Treat depending on culture results
-Topical clotrimazole (trade name canesten)
-Gentamicin 0.3% drops

Question 50

what is the first line abx in acute sinusitis?

Answer 50

phenoxymethypenicillin
second line- doxycycline

Question 51

what usually causes acute sinusitis?

Answer 51

Haemophilus influenzae, Streptococcus pneumoniae and Streptococcus pyogenes