Infectious Diseases of the Oral Cavity

Question 1

What is the name of the spirochete that causes syphilis?

Answer 1

Treponema pallidum

Question 2

Describe primary syphilis.

Answer 2

• chancre presents as painless ulcer with indurated margin
• most commonly presented on genitals but primary lesions may arise on oral mucosa
• associated with a painless regional lymphadenopathy
• resolves without therapy in 3-12 weeks

Question 3

Describe secondary syphilis.

Answer 3

• develops following latent period of several weeks
• fever, flu-like symptoms, generalized lymphandenopathy
• maculopapular rash develops with variable cutaneous and oral mucosal distribution
• oral mucosal “mucous patches” range from subtle to dramatic in appearance
• symptoms and lesions resolve over a 6 to 8 week period

Question 4

During what stage do serological tests return positive for syphilis?

Answer 4

Secondary

Question 5

Describe tertiary syphilis.

Answer 5

• develops in ~1/3 of untreated patients
• while the most serious aspects of tertiary syphilis consist of cardiovascular/neurovascular manifestations, oral lesions do occur

Question 6

What are two lesions that affect the oral cavity in tertiary syphilis?

Answer 6

1. Syphilitis glossitis
2. Gumma - focal destructive granuloma
   - develops mainly on skin and mucosa, but can affect viscera and bones
   - palate commonly involved (mucosa and bone)

Question 7

Describe congenital syphilis.

Answer 7

• treponema pallidum can cross placental barrier during 3rd trimerster of prgenancy
• congenital manifestations can range from minor flu-like symptoms and skin rash to major organ malformation and spontaneous abortion

Question 8

What is Hutchinson’s triad of congenital syphilis?

Answer 8

• interstitial keratitis (eye infection that often leads to blindness)
• VIII cranial nerve damage (deafness)
• mulberry molars and hutchinson’s incisors

Question 9

Which stages of syphilis have lesions infectious by contact?

Answer 9

• primary and secondary

- tertiary stage has no spirochetes so it’s not transmissible

Question 10

What species causes tuberculosis?

Answer 10

Mycobacterium tuberculosis

Question 11

What caused a change in frequency of oral lesions from bovine tuberculosis?

Answer 11

• routine pasteurization of milk

Question 12

What about TB now causes oral lesions and where are they most common?

Answer 12

• a hematogenous spread of disseminated TB or direct implantation from coughing up infect sputum (most common)
• most common on tongue, palate and gingiva

Question 13

Describe an oral lesions caused by TB.

Answer 13

• present as chronic, indurated ulcer that can be mistake for squamous cell carcinoma, esp. if cervical lymph node involvement.

Question 14

How long are oral lesions caused by TB infectious for?

Answer 14

until 2 weeks after systemic therapy initiated

Question 15

Describe Actinomycosis.

Answer 15

• Caused by actionomyces israeli species
• anaersobic gram-positive filament
• normal oral flora, but also found in carious lesions and necrotic pulp canals

Question 16

What signifies a colony of A. israeli?

Answer 16

• if pus draining from a chronic lesion contains small yellow granules (“sulphur granules)”

Question 17

How do you treat actinomycosis?

Answer 17

long-term, high-dose antibiotic regime and surgical debridement.

Question 18

What is Oral Candidiasis?

Answer 18

an opportunistic infection caused by candida albicans - a commensal form of yeast in most healthy mouths
- occurs commonly in uncontrolled diabetics, AIDS patients, people using predisposing medications (xerostomic inducing)

Question 19

What are examples of predisposing medications to oral candidiasis?

Answer 19

• corticosteroids
• broad spectrum antibiotics
• cancer chemo therapy (immune suppressant causing mouth ulcers)

Question 20

What’s the difference between thrush and atrophic oral candidiasis?

Answer 20

Thrush - pseudomembranous candidiasis (rubs off)

Atrophic - less apparent in diagnosis, but more common than thrush, presents with red area

Question 21

What is definitive for a diagnosis of oral candidiasis?

Answer 21

• cytology smear is superior to culture

Question 22

What type of infection is herpes simplex?

Answer 22

Viral

Question 23

What population of adults are seropositive for HSV-1?

Answer 23

90%

Question 24

Describe primary herpetic gingivostomatitis.

Answer 24

• incubation period - several days to 2 weeks
• prodrome: fever, headache, cervical lympadenopathy
• attached or unattached mucosa
• self-limiting
• acute episode resolves in 7-10 days, without scarring
• virus migrates along periaxonal sheath of trigeminal nerve to trigeminal ganglion, where it may remain in a latent or quiescent state
• reactivation/recurrent lesions occur in 35% of seropositive individuals

Question 25

Describe recurrent herpes simplex.

Answer 25

• mild prodromal symptoms of tingling, burning or pain followed by sequence of erythema, vesicle and secondaey ulceration
• most commonly occur on lip

Question 26

What is Coxsackie Virus (RNA)?

Answer 26

a group of picornaviruses, some of which can produce vesicular lesions of the oral mucosa (with or without skin lesions)

Question 27

What is herpangina?

Answer 27

• lesions involve more posterior areas of mouth and pharynx

- absence of fiery red gingival involvment

Question 28

What causes hand, foot and mouth disease?

Answer 28

Coxsackie A16

Question 29

What do herpangina and hand,food and mouth disease have in common?

Answer 29

They are both self limiting