fungi-like bacteria. aerobic gram-positive bacteria nocardia, rhodococcus, actinomadular,...
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Fungi-like Bacteria
Fungi-like Bacteria
Aerobic gram-positive bacteria
Nocardia, Rhodococcus, Actinomadular,
treptomyces, …
Anaerobic gram-positive bacteria
Actinomyces, Peptostreptococcus, Propionibacterium,
Lactobacillus,…
Actinobacteria Actinobacteria (Actinomycetes)(Actinomycetes)
ActinomycetesActinomycetesFilamentous, Branching BacilliNonmotileMay produce mycelium
Gram + and may be acid-fastliving normally in oral cavity, tonsils and intestines and also in soil.Some aerobic and some anaerobicActinomyces and Nocardia primary genera involved in Actinomycosis
ActinomycesActinomyces
Actinomycosis (Lumpy jaw)
Non-spore forming (mostly) anaerobic gram-positive bacteria
Colonize the upper respiratory tract, oral cavity
The most common cause is A. israelii, a normal flora
Modified acid fast (1% instead of 20% H2SO4) : Negative
An Endogenous infection & Painful bscesses in Cervicofacial• Common complication of tooth extraction,
poor oral hygiene and rampant dental caries.• Oral Actinomyces play significant role in
development of plaque and dental caries.Thoracic Abdominal
The outbreak is unrelated to age, sex, season, or occupation.
ActinomycosisActinomycosis
Actinomycosis (cont.)Actinomycosis (cont.)
Starts with a trauma moving bacteria inside the mucosa.
Actinomycosis characterized by:
- abscesses grow larger as the disease progresses, often over months.
- A chronic granolomatous disease.
- Purulent
PathogenesisPathogenesis
AbscessAbscess and lesions with fibrous walls and pus with sulfur granules develop.
GranulesGranules include: macrophages, other histologic cells, fibrin and bacteria. The edges of bacteria have come out of these granules.
Symptoms and signs of ActinomycosisSymptoms and signs of Actinomycosis
Laboratory DiagnosisLaboratory Diagnosis
Prompt transport of specimens to laboratory in anaerobic device
Direct examination
“Sulfur granule” (10x) Exudate from an abdominal wound
infection
Lab diagnosis:by Exudates, Pus and drainage samples
MicroscopicExamined for granules (1 mm), yellow colorCrushed between two slides.
CultureWashed several time in sterile distilled waterCrushed with sterile glass rod, and inoculated onto media.
Laboratory DiagnosisLaboratory Diagnosis
Direct examination
The delicate filamentous bacilli (arrow) at the peripheral of crushed gra
nule
Laboratory DiagnosisLaboratory Diagnosis
Culture
BHI, BA, Thioglycolate broth
Aerobic condition Anaerobic condition
370C 370C
Molar tooth colony
NOCARDIANOCARDIAAerobic
Saprophytes in soil, water
Branching filament
Fragmentation rod, coccoid form
Gram-positive beaded form
Nocardia asteroidesNocardia asteroidesNocardia brasiliensisNocardia brasiliensis
GPB, Catalase +, urease +, parafine hydrolysis
Colonies: grow in about 1 week, irregular, outstanding, different pigments (white, orange, red).
NOCARDIANOCARDIA Cell wall; mycolic acid (wax-like cell wall)
Modified acid fast (1% instead of 20% H2SO4)
Acid fast
Nocardia causes mostly opportunistic infections (in AIDS, Tuberculosis….)
TransmissionTransmission
Normally found in soil, these organisms cause occasional sporadic disease in humans sporadic disease in humans and animalsanimals.
Noccardia is an oral microfloraoral microflora. Also in the normal normal gingiva and periodontal pockets gingiva and periodontal pockets along with other species, such as Actinomyces.
Nocardia brasiliensisNocardia brasiliensis causes lobar pneumonia lobar pneumonia (pulmonary disease similar to TB).
Fever
abscess
chest pain
different from TB by lack of granoluma.
NocardiosisNocardiosisIt is most common in men with a compromised immune system.
In patients with brain infection, mortality exceeds 80%.
In other forms, mortality is 50%, even with appropriate therapy.
TreatmentTreatment
Penicillin for 6-12 months
NocardiosisNocardiosis
Laboratory DiagnosisLaboratory Diagnosis
Direct examination
Sputum, pus, tissue biopsy
Gram’stain Modified acid fast : positive
GPB, branching
Laboratory DiagnosisLaboratory Diagnosis
Culture
BHI, SDA, BA, Thayer-martin agar
- Glabrous, folded, heaped
- White to pink, orange
Nocardia brasiliensis, SDA, 300C, 9 days
Laboratory DiagnosisLaboratory Diagnosis
IdentificationIdentification
Biochemical test: 1. Resistant to Lysozyme
2. Paraffin hydrolysis
Lysozyme test
Right : resistant to lysozyme
Left : not grow in the presence of
lysozyme
IsolationIsolation
Paraffin baiting techniqueParaffin baiting techniqueGlass rod coat with paraffinMcClung’s carbon free brothIncubate 370C, 2 weeks
Laboratory DiagnosisLaboratory Diagnosis
StreptomycesStreptomyces
Antibiotic production
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