Listeria And Actinomycetes

Question 1

Listeria motility

Answer 1

Differential motility

• pEritrichous flagella at room temp, atrocious at 37° C

Tumbling motility (end on end)

Question 2

Psychrotrops meaning

Answer 2

Bacteria that can grow < 20° C

Question 3

Antons test

Answer 3

Inoculation in eye of guinea pig : produces keratoconjunctivitis

Question 4

Selective medium

Virulence factors

Answer 4

PALCAM agar

• LLO (listerolysin)
• proteins A and B
• Act A

Question 5

Listeriosis

Transmission
Clinical

Answer 5

Ingestion of raw milk, cheese, deli meats refrigerated foods

Clinical :
1. Pregnant females
- Chorioamnionitis - spontaneous abortion, still births
- Granulomatous infantiseptica (skin pustules and visceral abscesses)

2. Elderly
   Meningitis
   2nd m/c cause of meningitis
3. Healthy adults
   - gastroenteritis
4. Perinatal
   Neonatal meningitis and septicemia

Question 6

Actinomyces

Answer 6

Non capsulated, non sporing , non motile

Molar tooth colonies : nutrient agar , blood agar

Question 8

Nocardia :

________ saprophyte
______ acid fast
Uses ________ as sole source of growth (what technique for isolation)

Answer 8

Soil
Partially (containers mycolic acid in cell wall)
Carbon as source (Paraffin bait technique) m

Question 9

CMN group ( mycolic acid present)

Answer 9

Corynebacteria : non acid fast
Mycobacterium: acid fast
Nocardia : partially acid fast

Question 10

Nocardiosis

Transmission
Types
Tx

Answer 10

Transmission
1. Cutaneous nocardiosis : traumatic implantation
- Cellulitis
- Spiritrichoid lesions
- Actinomycetoma ( sinuses with granules)

2. Pleuropulmonary
   - Inhalation
   - in immunocompromised
   - penumonia + pleural effusion+ cavities

Question 11

Actinomycese vs Nocardia

Gas requirements
ZN stain
Location
Disease
DOC

Answer 11

Actino. Nocardia
1. Anaerobes. Aerobes
2. Non acid fast. Partially
3. Commensals. Environment
4. Endogenous. Exogenous
5. Penicillin. Sulfonamides