Meningococcal disease

What organism causes meningitis?

Streptococcus pneumoniae (pneumococcus) and Neisseria meningitidis (meningococcus), which are common in children and adults

Group B Streptococcus and E. coli, which are common in babies under 3 months old.

• Haemophilus influenzae type b (Hib) used to be common but is now rare in areas with vaccination

what bacteria causes meningococcal meningitis

 Neisseria meningitidis, a Gram-negative diplococcus.

where does neisseria meningitis colonise

The nasopharynx (10–25% carriage).

Which virulence factor allows Nm to attach to epithelial cells?

 Type IV pili (T4P) -  Long attachment organelles which bacterium use to intimately  attach to certain receptors.

What enzyme helps Nm evade mucosal immunity?

IgA protease - Protease cleave IgA which is produced in the humoral response to pathogen preventing from doing function, meaning bacteria not cleared and can continue to establish self in upper air way

What clinical sign is a red flag for meningococcal disease?

Non-blanching rash.

 How does Nm cross the BBB?

Via T4P adherence (PilE/PilV → CD147), paracellular entry, or transcytosis.

What is pleocytosis?

Increased white blood cells in CSF.

First-line antibiotic for suspected meningococcal meningitis in ≥3 months old?

IV ceftriaxone.

Duration of antibiotic therapy for confirmed meningococcal meningitis?

7 days.