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Flashcards in Microbiology of ENT infections Deck (46):
1

What are the signs and symptoms of viral vs bacterial tonsillitis? What is the diagnosis?

Viral:
¥ Malaise
¥ Sore throat, mild analgesia requirement
¥ Temperature
¥ Able to undertake near normal activity
¥ Possible lymphadenopathy
¥ Lasts 3-4 days

Bacterial:
¥ Systemic upset,
¥ Fever
¥ Odynophagia
¥ Halitosis
¥ Unable to work / school
¥ Lymphadenopathy
¥ Lasts ~1 week, requires antibiotics to settle.

Diagnosis:
-throat swab

2

Do the majority of tonsillitis need abiotics? Which criteria are used to assess whether abiotics are needed? what other treatment exists?

no

Centor criteria:
-fever
-purulent tonsils
-cervical lymphadenopathy
-no cough
Give each factor a point and add on if below 15years and take 1 off if above 45years.
¥ 0 or 1 points - No antibiotic (risk of bacterial infection <10%)
¥ 2 or 3 points - Should receive an antibiotic if symptoms progress (Risk of infection 32% if 3 criteria, 15% if 2)
¥ 4 or 5 points - Treat empirically with an antibiotic (Risk of infection 56%)


Treatment:
-supportive (eat/drink/rest/NSAIDs)
-IV fluids/steroids if in hospital

3

What abiotics are used in tonsillitis?

Unable to swallow:
-IV benzylpenicillin 1.2g qds
-if penicillin allergic clarythromycin IV 500mg BD

Able to swallow:
-oral penicillin V 500mg QDS or 1g BD 10days
-clarythromycin PO 500mg bd 5days

4

What is the most common bacterial cause of tonsillitis?

What are the common viral causes of tonsillitis?

-Group A strep (aka strep. pyogenes)
(gram +ve cocci in chains / beta haemolytic)

Viral:
-EBV, rhinovirus, influenza, parainfluenza, adenovirus, enterovirus

5

What are three acute complications of strep. pyogenes?

Ð Peritonsillar abscess (quinsy)
Ð Sinusitis/ otitis media
Ð Scarlet fever

Strep. Pyogenes Quinsy:
Infection control – SICP’s/Contact precautions/risk assess for droplet precautions

6

What are two late complications of tonsillitis?

Rheumatic fever
Ð 3 weeks post sore throat
Ð fever, arthritis and pancarditis

Glomerulonephritis
Ð 1-3 weeks post sore throat
Ð haematuria, albuminuria and oedema

7

When is surgery indicated for tonsillitis?

-if sore throat due to tonsillitis
-episodes = disabling and prevent normal function
-7+ episodes in preceding year or 5+ episodes in each preceding 2 years or 3+ episodes in each year for preceding 3 years

8

What is glandular fever? what symptoms are seen?

Infectious mononeucleosis (“Mono”)
¥ Ebstein-Barr virus (EBV)

Ð Disease of young adults
¥ Fever
¥ Enlarged lymph nodes
¥ Sore throat, pharyngitis, tonsillitis
¥ Malaise, lethargy

Classic triad – fever/pharyngitis/lymphadenopathy

9

What signs are seen in glandular fever?

¥ Gross tonsillar enlargement with membranous exudate
¥ Marked cervical lymphadenopathy
¥ Palatal petechial haemorrhages
¥ Generalised lymphadenopathy
¥ Hepatosplenomegaly (splenomeglay 50%)
¥ Jaundice 5%/hepatitis 15%
¥ Rash

10

What is the diagnosis of glandular fever?

¥ Low CRP (<100)
¥ Heterophile antibody
Ð +ve Paul-Bunnell test
Ð +ve Monospot test
¥ Epstein-Barr virus IgM
¥ Blood count and film : Atypical lymphocytes in peripheral blood and leukocytosis (lymphocytosis)

11

What is the treatment of glandular fever? what are the complications?

¥ Symptomatic treatment
¥ Do NOT prescribe ampicillin (amoxicillin)
¥ diagnostic generalised macular rash will result!
¥ Antibiotics
Steroids

¥ Bed rest – for malaise
¥ Paracetamol – for fever
¥ Avoid sport 6 weeks
¥ Antivirals not clinically effective
¥ Corticosteroids may have a role in some complicated cases – (dangerous)


Complications:
Fever and pharyngitis lasts 2-4wks but lethargy may last longer
¥ Protracted but self limiting illness
¥ Anaemia (this is autoimmune and treated via steroids),
¥ Thrombocytopenia (usually mild and may not need steroids)
¥ Splenic rupture – avoid sport 6weeks
¥ Upper airway obstruction
¥ Increased risk of lymphoma, especially in immunosuppressed.

12

What symptoms are seen with quinsy?

¥ Unilateral throat pain and odynophagia
¥ Trismus
¥ 3-7 days of preceding acute tonsillitis
¥ if severe dysphagia

"hot potato voice"

13

What are the signs seen in quinsy?

-medial displacement of tonsil and uvula
-concavity of palate lost

14

What is the treatment for quinsy?

-Aspiration

Antibiotics:
-Benzylpenicillin IV 1.2g qds or Penicillin V oral 500mg qds or 1g bd
. Total duration IV/PO: 10 days
Penicillin allergy:
Clindamycin PO 450mg tds
(10 days)
-If unable to swallow IV Clindamycin 600mg–1.2g qds

If not resolving at 48 hours consider adding metronidazole to penicillin
.(clindamycin gives adequate anaerobic cover)

15

What is chronic tonsillitis??

¥ Chronic “sore throat”
¥ “Malodorous breath”
¥ Presence of tonsilliths
¥ Peritonsillar erythema
¥ Persistent tender cervical lymphadenopathy
¥ Surgery has controversial role
¥ Rarely offered

This is when the tonsils naturally atrophy as get older and holes in tonsils get wider and material leaks out and is left behind. This will clear up in time and does not need treatment.

16

What is diphtheria caused by?

Corynebacterium diphtheriae

17

What are the clinical features of diphtheria?

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

18

What is the treatment for diphtheria?

¥ Treatment: Antitoxin and Supportive and Penicillin/erythromycin

19

Why is diphtheria rare in this country?

¥ Vaccine - The vaccine is made from a cell-free purified toxin extracted from a strain of C. diphtheriae.

-more common in other countries e.g. Russia

20

What is the cause of oral thrush?

¥ Candida albicans

21

What is seen clinically in oral thrush?

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

22

What is the treatment for oral thrush?

Nystatin

23

What is acute otitis media? who is affected? what is the presentation?

¥ An upper respiratory infection involving the middle ear by extension of infection up the eustachian tube
¥ Predominantly disease of infants and children
¥ Present with earache

This is an acute inflammation of the middle ear causing severe pain (otalgia) and conductive hearing loss as fluid accumulation in the middle ear prevents conduction of sound. (it may or may not have an accumulation of fluid)

24

What are the causes of acute otitis media?

¥ Often viral with bacterial secondary infection
Most common bacteria: Haemophilus influenzae, Streptococcus pneumoniae and Streptococcus pyogenes

25

What is the diagnosis of acute otitis media?

• swab of pus if eardrum perforates – otherwise samples cant be obtained

26

What is the treatment of acute otitis media?

¥ 80% resolve in 4 days without antibiotics.

Antibiotics for AOM < 2yrs or AOM with otorrhoea:
-amoxicillin 5 days
-clarithromycin 5 days if penicillin allergic

27

what is considered as recurrent AOM?
What is a complication of AOM?

3 or more episodes in 6mths
5 or more episodes in 12months

• The infection may spread to the mastoid area and if there is tenderness and swelling around this area then an urgent ENT opinion should be obtained.

28

Acute sinusitis:
-what is this?

¥ Mild discomfort over frontal or maxillary sinuses due to congestion often seen in patients with upper respiratory viral infections.
¥ However, severe pain and tenderness with purulent nasal discharge indicates secondary bacterial infection

29

What is the treatment of acute sinusitis?

¥ In uncomplicated avoid antibiotics as 80% resolve in 14 days without antibiotics.
¥ Where indicated
¥ 1ST LINE penicillin V
¥ 2ND LINE doxycycline –NOT IN CHILDREN!!!

30

What is otitis externa?

¥ Inflammation of the outer ear canal

31

What are the clinical features of otitis externa?

Ð Redness and swelling of the skin of the ear canal.
Ð It may be itchy (especially in the early stages).
Ð Can become sore and painful.
Ð There may be a discharge, or increased amounts of ear wax.
Ð If the canal becomes blocked by swelling or secretions, hearing can be affected.
Ð Common in swimmers that don’t dry their ears

• Debris may be in the canal which needs to be removed by gentle mopping or preferably by suction viewed directly under microscope
• In severe cases the canal may be swollen and a view of the tympanic membrane may be impossible
• Any foreign body seen should be removed by trained personnel.

32

What are the bacterial and fungal causes of otitis externa?

Bacterial causes
Ð Staphylococcus aureus
Ð Proteus spp
Ð Pseudomonas aeruginosa
Fungal causes
Ð Aspergillus niger (black heads of the funghi)
Ð Candida albicans

33

What is the management of otitis externa?

Mild (mild discomfort and/or pruritus; no deafness or discharge):
-do not swab
-acetic acid 2% (earcalm) for 7 days
-if doesn't improve after 3 days = moderate

Moderate:
-do not swab
-gentisone HC, locortem vioform, otomize or sofradex
-if unresponsive then swab and treat according to sensitivities considering topical gentamicin or cipro (as 0.3% eye drops 3 drops BD)
-include topical corticosteroid for ear canal oedema

If cellulitis/disease extends out of ear canal:
-oral or IV abiotics REFER ENT

If fungal cause:
-clotrimazole solution 1% 2-3times daily until 14 days after cure

Moderate if:
a red, oedematous ear canal which is narrowed and obscured by debris
conductive hearing loss
discharge
regional lymphadenopathy
cellulitis spreading beyond the ear
fever

34

What is the viral cause for oral ulceration?

Herpes simplex 1 virus

35

What is the primary gingivostomatitis due to HSV-1?
-how long can this take to recover?
-what treatment can be used?

¥ Disease of pre-school children
¥ primary infection
¥ systemic upset
¥ lips, buccal mucosa, hard palate
¥ vesicles 1-2mm
¥ ulcers
¥ Fever, local lymphadenopathy
¥ May take up to 3 weeks to recover
¥ spread beyond mouth
¥ aciclovir treatment

36

What is the latent phase of HSV1?

After primary infection an inactive form of the virus resides in sensory nerve cells which can reactivate to re-infect mucosal surfaces

37

What is a cold sore?
What can be used as treatment?

¥ Reactivation from nerves causes active infection
¥ various stimuli
¥ aciclovir therapy or suppression
¥ not all reactivations are symptomatic
¥ Aciclovir does not prevent latency

38

Does everyone get clinical recurrence of cold sores? what is herpetic whitlow?

Although multiple cycles of latency and active infection possible and natural history is for decreasing frequency Only half of infected people get clinical recurrences

¥ recurrent intra-oral lesions are rarely HSV

Herpetic whitlow is the infection around finger nail – wear gloves!

39

What is the lab confirmation of HSV?

¥ Swab of lesion in virus transport medium
Ð detection of viral DNA by PCR

40

What is herpangina?

¥ Vesicles/ulcers on soft palate

41

What causes herpangina? who is afected? what is the diagnosis?

¥ coxsackie viruses (not HSV)
Ð enterovirus
¥ similar patient age range to 1ry HSV gingivostomatitis
¥ diagnosis clinically or by PCR test of swab in viral transport medium

42

What is hand foot and mouth disease caused by?

¥ coxsackie viruses (enteroviruses)

43

What kind of outbreaks are common for hand, foot and mouth disease? What is the diagnosis?

¥ family outbreaks common
¥ diagnosis clinically or by PCR test of swab in viral transport medium

44

What is ramsay hunt syndrome?

Ramsay Hunt syndrome (herpes zoster oticus) is caused by the reactivation of the varicella zoster virus in the geniculate ganglion of the seventh cranial nerve.

45

What are the clinical features of ramsay hunt syndrome?

auricular pain is often the first feature
facial nerve palsy
vesicular rash around the ear
other features include vertigo and tinnitus

46

What is the management of ramsay hunt syndrome?

oral aciclovir and corticosteroids are usually given