Commensal and Pathogenic Microorganisms Flashcards
What kind of infection is candida infection?
Candida is an opportunistic infection.
What are the 5 signs of inflammation?
Local hyperthermia, fever
Hyperemia (redness)
Tissue swelling
Burning pain
Functional impairment
How common are infectious disease deaths?
> 10 million deaths annually
Most occur in children especially from resp and diarrhoeal infections
US 2 of the top 10 causes of death are infectious.
What are the classifications of infectious?
According to clinical appearance
What are the types of infections according to clinical appearance?
Acute infections
Chronic infections
Acute exacerbation of chronic infection
What are eg of types of infection based on etiological agent?
Bacterial
Viral
Fungal
Parasitic
What are eg of types of infection based on source of infection?
Odontogenic
Secondary infections of lesions such as cyst or tumours
Infections that arise from contaminated wound or trauma
Iatrogenic infections
Why are commensal microflora so important?
1/10 cells in our body are human cells
They protect our body from invasion by pathogenic microorganisms
Where is oral microflora located?
Oral biofilm covers teeth, mucosal surfaces, and the gingival sulcus
What is the oral microflora composed of?
Aerobic gram-positive cocci
Anaerobic gram-positive cocci
Anaerobic gram-negative rods
What kind of relationship is there between human and oral microflora?
Mutualism
What kind of microbial organisms are present in the gingival crevice/pocket?
In health, aerobic. In disease, anaerobic
What factors affect the growth of microorganisms in the oral cavity?
Temperature
pH
Nutrients
Host defenses
Host genetics
Antimicrobial agents and inhibitors
What life changes influence the oral microflora?
Loss of teeth
Age
Eruption of teeth
Dentures
Why are streptococci very cariogenic?
They can grow on hard tissue
Which streptococci are associated most with endocarditis?
In order of most common to least common:
S. mitior
S. sanguis
S. mutans
Which oral streptococci are associated most with endocarditis?
In order of most common to least common:
S. mitior
S. sanguis
S. mutans
Which streptococci are most cariogenic?
S. mutans > S. sanguis > S.mitior
What changes occur to oral microbiota during disease?
Fungal-bacterial dysbiosis
Altered PRR, TLR, NOD-like, C-type lectin receptor expression
Candida invasion
Epithelial damage
What causes odontogenic infections?
Odontogenic infections arise from teeth and have a characteristic flora. They arise from indigenous bacteria that normally live on the host.
They are often initiated by caries, periodontal disease, and pulpitis and spread beyond teeth to the alveolar process and to the deeper tissues of the face, oral cavity, head, and neck
Which bacterial species are likely to cause odontogenic infections?
5 main species that are likely to cause infection.
How should odontogenic infections be treated?
Broad spectrum antibiotics such as Amoxycillin
How does bacterial composition differ by type of infection?
Early infections appearing as a cellulitis are predominantly aerobic streptococcal infections. Oedema is a sign of aerobic
Late, chronic abscesses may be characterized as anaerobic infections
What are the types of odontogenic infections?
Periapical (starting from a periapical abscess)
Periodontal (Starting from a periodontal pocket or from pericoronitis)
Where does the infection typically go following a periapical infection?
Infection erodes through the thinnest bone. (easiest pathway)
When the apex is below the attached muscle vestibular abscess results.
If apex is higher than muscle attachment, the adjacent fascial space is involved.
What are the types of host defense mechanisms?
Local defenses: Intact anatomic barrier and indigenous bacteria
Humoral defenses: Immunoglobulins, and complement
Cellular defenses: Phagocytes and lymphocytes
What are some causes of medical compromise in some patients?
Uncontrolled metabolic disease: Diabetes, alcoholism, and malnutrition
Suppressing disease: Leukaemia, lymphoma, and malignancy
Suppressing drugs: Chemotherapeutic agents, and immunosuppressives
What is tubercolosis?
A chronic granulomatous disease caused by various strains of mycobacteria usually seen in humans.
How common is TB?
nearly 8.6 million infected with TB disease
Increased in prevalence due to multi-drug resistant tubercolosis
What are the oral manifestations in tubercolosis?
0.5 - 1% of all TB patients show them
Saliva is very contagious
Lesions form on oral mucosa.
Cervical lymphadenopathy: Tender, irregular, and enlarged.
What are the measures of immune system reaction in TB?
Erythrocyte sedimentation rate
WBC count
Differential WBC count
Neutrophils
Basophils
