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