M12- Oral spirochaetes Flashcards
Describe spirochaetes.
• 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
where is spirochetes very common?
-in the mouth
– Usually associated with deep periodontal pockets
– numbers increase dramatically in periodontitis
Describe the shape of spirochaetes.
• Spirochaetes are helical bacteria
• central protoplasmic cylinder (cell)
• contains 3-5 axial filaments or endoflagellae within the outer cell envelope
(moves with corkscrew action)
what genus is in spirochaetes?
Treponema
what is lime disease?
– Tickborne(zoonotic), temeperate countries
– Miceprimaryreservoir,tickto deer, deer tick to man
– Slow growing, microaerophilic, spirocheate
what is the primary infection of lymes disease?
red spot at bite site, enlarges with pale area in the middle
what are the symptoms of lymes disease?
– Headache, drowsiness,mild fever, joint/muscle pain, swollen lymph glands
what do 15% of people develop 1-5 weeks after bite?
neuro borrelia
what are the symptoms of neuro borrelia?
- 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
what organism causes syphillus?
treponema pallidum
what are the primary symptoms of syphillus? (3 days- 3 months)
-painless sore ‘chancre’
penis,vulva, mouth
what are the secondary symptoms of syphillus? (2 weeks- 24 months)
-rash and ‘flu-like’ symptoms
lymph nodes, liver, spleen skin
what are the latent symptoms of syphillus? (1-30 years)?
occasional rash (liver/spleen dormant and periodic reactivation )
what are the tertiary symptoms of syphillus? (1- >30 years)?
neuro and/or cardio vascular
(madness, paralysis , CV lesions , heart failure etc
what is congenital syphilis?
vertical transmission / mother infant to infant
what is the treatment of syphilis?
penicillin
3 injections -1 per week for latent syphilis
what can increases in syphilis be related to?
certain burrows
what species has a loose association at edge of sub gingival plaque?
oral treponemes
Name two treponeme species and identify which one is in the red complex.
– Treponema vincentii
– Treponema denticola
Describe T. denticola.
• 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)
what is T.denticola commonly associated with in chronic perio lesions?
P. gingivalis
where do T. denticola and P. gingivalis found to co-aggregate?
in vitro
where are T. denticola and P. gingivitis grown?
in mixed biofilms
what is Acute necrotising ulcerative gingivitis (NG)?
An acute painful true infection of the gingivae
relatively rare in developing countries
what is NG associated with?
immunosuppression : – Poor & neglected oral hygiene – Plaque retentive factors (overhangs, crowded teeth, calculus) – Smoking – Malnutrition, – Systemic illness ; HIV – Stress
what are symptoms of NG?
inflammation, spontaneous bleeding, grey pseudomembrane, intense pain & even clear evidence of tissue destruction
how can NG be described?
rapidly destructive non-communicable gingival infection of complex aetiology
what is the historical view of NG?
Historical view a fuso-spirochaetal complex (based on microscopy) – Fusobacterium nucleatum & Treponema vincentii
what is often present in large number in NG?
prevotella intermedia
what is the current view of NG?
more polymicrobial with multiple species of Spirochaetes & Fusiform bacteria found in lesions
How does NG present?
• Acutely Inflamed – red/shiny • Bleeding • Ulcers • Pseudomembrane covers lesions – Leucocytes – Erythrocytes – Fibrin – Necrotictissue – Bacteria
what effect does release of volatile compounds H2S in NG have?
bad smell
What is Vincent’s angina?
- Infection of Pharynx
- Unilateral sore throat
- Increased intensity over several days
- Referred Earache
- Bad taste in mouth
- Halatosis
- Deep ulcer of one tonsil
Treponema vincentii (murine abscess model).
• 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%)
Name 3 treatments of NG.
• 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
what is cancrum oris (NOMA)?
- severe gangrenous disease of soft tissue
- severe form of ANUG
- seen in children in developing countries
what is the typical patient of cancrum oris (NOMA)?
– Malnourished,
– < 10 yrs & may have a recent history of measles or leukemia
what causes cancrum oris (NOMA)?
Original gingival infections spread into the cheeks & face.
– causing extensive tissue loss and facial disfigurement
