OSPE Haemophilus influenzae- Bacterial meningitis

Question 1

case

Answer 1

-high grade fever, headache and vomiting.
-signs of meningism.
-CSF was sent for Gram stain and culture.

Question 2

Gram-stain

Answer 2

• pus cells seen
• Both intracellular and extracellular GNCB seen
• Pleomorphic: Few bacillary and even filamentous forms
• Presumptive diagnosis: Hib meningitis

Question 3

culture

Answer 3

Requires :
*X factor: Hemin,present freely in the blood
* V factor: NAD, present inside RBCs

Chocolate agar
* RBCs lysed due to heating
* NAD released
* NADase inactivated by heat

Blood agar: Satellitism

Specialized media for H.influenzae:
1. Levinthal’s agar
2. Fildes’ agar

Question 4

Serotyping

Answer 4

Latex agglutination test