M12- Oral spirochaetes

Question 1

Describe spirochaetes.

Answer 1

• Gram -ve cell wall
– most spirochaetes do not stain well with Gram s stain
• Fastidious
– extremely difficult to grow in the laboratory
– either on agar or in broth

Question 2

where is spirochetes very common?

Answer 2

-in the mouth
– Usually associated with deep periodontal pockets
– numbers increase dramatically in periodontitis

Question 3

Describe the shape of spirochaetes.

Answer 3

• Spirochaetes are helical bacteria
• central protoplasmic cylinder (cell)
• contains 3-5 axial filaments or endoflagellae within the outer cell envelope
(moves with corkscrew action)

Question 4

what genus is in spirochaetes?

Answer 4

Treponema

Question 5

what is lime disease?

Answer 5

– Tickborne(zoonotic), temeperate countries
– Miceprimaryreservoir,tickto deer, deer tick to man
– Slow growing, microaerophilic, spirocheate

Question 6

what is the primary infection of lymes disease?

Answer 6

red spot at bite site, enlarges with pale area in the middle

Question 7

what are the symptoms of lymes disease?

Answer 7

– Headache, drowsiness,mild fever, joint/muscle pain, swollen lymph glands

Question 8

what do 15% of people develop 1-5 weeks after bite?

Answer 8

neuro borrelia

Question 9

what are the symptoms of neuro borrelia?

Answer 9

• back pain (between shoulders, worse at night)
• distorted (numb) feeling at the site of the bite
• may present as meningitis (fever, headache, stiff neck)
• chronic - slow developing destruction of the nervous system

Question 10

what organism causes syphillus?

Answer 10

treponema pallidum

Question 11

what are the primary symptoms of syphillus? (3 days- 3 months)

Answer 11

-painless sore ‘chancre’

penis,vulva, mouth

Question 12

what are the secondary symptoms of syphillus? (2 weeks- 24 months)

Answer 12

-rash and ‘flu-like’ symptoms

lymph nodes, liver, spleen skin

Question 13

what are the latent symptoms of syphillus? (1-30 years)?

Answer 13

occasional rash
(liver/spleen dormant and periodic reactivation )

Question 14

what are the tertiary symptoms of syphillus? (1- >30 years)?

Answer 14

neuro and/or cardio vascular

(madness, paralysis , CV lesions , heart failure etc

Question 15

what is congenital syphilis?

Answer 15

vertical transmission / mother infant to infant

Question 16

what is the treatment of syphilis?

Answer 16

penicillin

3 injections -1 per week for latent syphilis

Question 17

what can increases in syphilis be related to?

Answer 17

certain burrows

Question 18

what species has a loose association at edge of sub gingival plaque?

Answer 18

oral treponemes

Question 19

Name two treponeme species and identify which one is in the red complex.

Answer 19

– Treponema vincentii

– Treponema denticola

Question 20

Describe T. denticola.

Answer 20

• Larger Genome than T. pallidum
• One of 60 species in Dental Plaque
• Asaccharolytic
• Most proteolytic member of the red complex
• Can attach to gingival fibroblast and induce cytotoxicity and cell death
• Stress responses
– Super oxide dismutase (SOD) activity
–Arginine deaminase (arginine to ammonia increasing pH)

Question 21

what is T.denticola commonly associated with in chronic perio lesions?

Answer 21

P. gingivalis

Question 22

where do T. denticola and P. gingivalis found to co-aggregate?

Answer 22

in vitro

Question 23

where are T. denticola and P. gingivitis grown?

Answer 23

in mixed biofilms

Question 24

what is Acute necrotising ulcerative gingivitis (NG)?

Answer 24

An acute painful true infection of the gingivae

relatively rare in developing countries

Question 25

what is NG associated with?

Answer 25

immunosuppression :
– Poor & neglected oral hygiene
– Plaque retentive factors (overhangs, crowded teeth, calculus)
– Smoking
– Malnutrition,
– Systemic illness ; HIV
– Stress

Question 26

what are symptoms of NG?

Answer 26

inflammation, spontaneous bleeding, grey pseudomembrane, intense pain & even clear evidence of tissue destruction

Question 27

how can NG be described?

Answer 27

rapidly destructive non-communicable gingival infection of complex aetiology

Question 28

what is the historical view of NG?

Answer 28

Historical view a fuso-spirochaetal complex (based on microscopy) – Fusobacterium nucleatum & Treponema vincentii

Question 29

what is often present in large number in NG?

Answer 29

prevotella intermedia

Question 30

what is the current view of NG?

Answer 30

more polymicrobial with multiple species of Spirochaetes & Fusiform bacteria found in lesions

Question 31

How does NG present?

Answer 31

• Acutely Inflamed – red/shiny
• Bleeding
• Ulcers
• Pseudomembrane covers lesions
– Leucocytes
– Erythrocytes
– Fibrin
– Necrotictissue  
– Bacteria

Question 32

what effect does release of volatile compounds H2S in NG have?

Answer 32

bad smell

Question 33

What is Vincent’s angina?

Answer 33

• Infection of Pharynx
• Unilateral sore throat
• Increased intensity over several days
• Referred Earache
• Bad taste in mouth
• Halatosis
• Deep ulcer of one tonsil

Question 34

Treponema vincentii (murine abscess model).

Answer 34

• Spirocheates mixture required
(40%)
• Cell associated proteolytic enzymes
– Production of Trypsin-Like Proteases
– N-acetyl-b-glucosaminidase
• Fusobacterium spp required
– Provide essential growth factors
– Suprisingly relatively few (3%)

Question 35

Name 3 treatments of NG.

Answer 35

• Intensive local oral hygiene
– e.g. use of ultrasonic scaler
• Oral hygiene advice and mouth-rinses 
– e.g. chlorhexidine
• Short course of Antibiotics 
– metronidazole therapy
– 200mg for 5 days

Question 36

what is cancrum oris (NOMA)?

Answer 36

• severe gangrenous disease of soft tissue
• severe form of ANUG
• seen in children in developing countries

Question 37

what is the typical patient of cancrum oris (NOMA)?

Answer 37

– Malnourished,

– < 10 yrs & may have a recent history of measles or leukemia

Question 38

what causes cancrum oris (NOMA)?

Answer 38

Original gingival infections spread into the cheeks & face.
– causing extensive tissue loss and facial disfigurement