Bacterial Infections

Question 1

Superficial infection of skin caused by Staphlococcus auerus or Streptococcus pyogens
easily spread in unsanitary conditions
peak occurance during summer/early fall, moist climates
most common in school aged children
Clinical: facial perioral & perinasal, erythemia w/ superficial vesicles that quickly rupture and crust over, amber color, itching common, arise in areas of damaged skin
Diagnosis: presumptive based on clinical presentation, definitive diagnosis requires isolation of causative organisms in culture of skin
TX: topical or systemic antibiotic

Answer 1

Impetigo

Question 2

What is a possible differential diagnosis for impetigo?

Answer 2

Herpes simplex

Question 3

common over wide age range, calcified structures that develops in enlarged tonsillar crypts,
Clinical: enlarged crypts w/ yellowish debris (soft or calcified), variable size, foul smelling, solitary or multiple, radiographically present as radiopacities in midportion of ascending ramus.
Tx: none necessary unless associated w/ clinical symptoms (usu. fall out on own

Answer 3

Tonsillolithiasis

Question 4

convoluted crypts of tonsils commonly filled w/ desquamated cells, foreign debris, and bacteria, soft deposits

Answer 4

tonsillar concretions

Question 5

calcified deposits in tonsillar crypts

Answer 5

tonsilloliths

Question 6

Chronic infection worldwide caused by Treponema pallidum (spirochete), spread by sexual contact, transplacental transmission, contaminated blood exposure, infection progresses through 3 stages, highly infectious in first 2 stages

Answer 6

Syphilis

Question 7

Relatively painless ulceration (chancre), develops 3-90 days after exposure, most affect genital area, 4% are oral –> lip, buccal mucosa, tongue, resolves spontaneously in 3-8 weeks
ulcerations are non-specific and require biopsy for diagnosis
Good prognosis if identified early

Answer 7

Primary syphilis

Question 8

develops 4-10 weeks after initial infection, generalized lymphadenopathy, erythematous maculopapular cutaneous eruption, mucous patches & condylomata lata of oral mucosa, split papules at angles of mouth, can often affect palm of hand and soles of feet
spontaneous resolution w/in 3-12 weeks but relapse may occur during the next year.
untreated pts enter latent period

Answer 8

Secondary syphilis

Question 9

What could be a possible differential for lymphadenopathy?

Answer 9

brachial cleft cyst, TB

Question 10

What could be a differential for a mucous patch related to syphilis?

Answer 10

pre-malignant lesion

Question 11

can someone in the latent period of syphilis still transmit the disease to others?

Answer 11

yes

Question 12

Develops after a latency period of 1-30 years, 30% of pts affected, may affect any tissue (vascular, CNS, skin, bones, soft tissues), gumma formation (necrotic lesions), oral involvement may produce palatal perforation

Answer 12

Tertiary Syphilis

Question 13

What could be a differential diagnosis for palatal perforation from tertiary syphilis?

Answer 13

aggressive lymphoma, nasal inhalation of recreational drugs

Question 14

Saddle nose deformity
saber shins
Hutchinson's Triad:
* malformed incisors/mulberry molars
* ocular interstitial keratitis (opacification of cornea)
*VIII nerve deafness

Answer 14

Congenital Syphilis

Question 15

Describe the histopathology of primary and secondary syphilis.

Answer 15

intense plasmacytic infiltrate

Question 16

Describe the histopathology of tertiary syphilis.

Answer 16

characterized by granulomatous inflammation

Question 17

What stain is used to identify spirochetes?

Answer 17

Warthin Starry stain

Question 18

What is a negative aspect to syphilis screening tests?

Answer 18

they are very sensitive, but not specific to any one type of spirochete

Question 19

When would you use dark-field microscopy?

Answer 19

When you have a non-oral syphilis lesion (b/c other spirochetes can be part of normal oral flora, does not work with oral lesions)

Question 20

What is the treatment for syphilis?

Answer 20

PCN

pcn allergy: use doxycycline, tetracycline, erythromycin

Question 21

caused by Mycobacterium tuberculosis, droplet transmission, endemicc in many areas of the world,
Clinical: on 5-10% infected pts progress to active, low grade fever, night sweats, fatigue, weight loss, chronic bloody cough, oral lesions rather uncommon, solitary chronic painless ulcer or granular lesion most common on gingiva or tongue, diagnose w/ PPD, chest radiograph, biopsy, culture (takes 4-6 wks), molecular testing
TX: combination of antibiotics
prognosis good in immunocompetent pt
emergence of resistant strains

Answer 21

tuberculosis

Question 22

Describe the histopathology of TB.

Answer 22

usually necrotizing granulomatous inflammation (caseous necrosis), multinucleated giant cells, organisms stain using fast acid method (Ziehl-Neelsen stain)

Question 23

caused by actinomyces species that normally inhabit mouth, often associated w/ local trauma, (55% in cervicofacial areas), may follow dental extraction or untx dental disease

Answer 23

Actinomycosis