ID - Meningitis

Question 1

name the common symptoms of meningitis

Answer 1

1. headache
2. neck stiffness
3. fever
4. photophobia
5. seizures

Question 2

name the common signs of meningitis

Answer 2

1. signs of meningeal irritation:
   
   • nuchal rigidity
   • +ve Kernig’s sign (pain and resistance on passive knee extension when hips are fully flexed)
   • +ve Brudzinski’s sign (hips flex on bending head forwards)
   • +ve JOLT test (worsened headache on rapidly moving head from side to side)
2. non-blanching petechial/purpuric rash (meningococcal meningitis)
3. cranial and peripheral n. examination: paresis (partial paralysis) and focal neurological deficits (inc.. abnormal pupils)
4. signs of shock, e.g. tachycardia, hypotension, resp. distress, altered mental state, decreased UO
5. bulging fontanelle (in infants)

Question 3

name the causative agents of meningitis in neonates, 2-5 yrs, 5-30 yrs and elderly/immunocompromised

Answer 3

• neonates: E. coli, L. monocytogenes, group B streptococci
• 2-5 yrs: H. influenzae type B
• 5-30 yrs: N. meningitides, S. pneumoniae, H. influenzae type B
• elderly: S. pneumoniae, L. monocytogenes, TB

Question 4

which Ix should be performed in a pt with suspected meningitis?

Answer 4

1. Lumbar puncture - perform immediately if no signs of RICP (do CT head if doubt)
2. Bloods
   - FBC: raised WCC
   - CRP: raised
   - UandEs: assess renal function
   - coagulation screen: ?DIC
   - blood culture and whole blood PCR for N. meningitidis (in children and young adults)
   - blood glucose
   - ABG: ?metabolic acidosis/sepsis
3. Bedside tests
   - urine, stool and nasal swab: culture and virology
4. Imaging
   - CXR: >lung abscess
   - MRI head: if ?complications

Question 5

how would you manage a pt with suspected meningitis in a pre-hospital situation?

Answer 5

Single dose of IV BENZYLPENICILLIN (or IM if vein not available) at earliest opportunity:

• <1 yr - 300 mg
• 1-9 yrs - 600 mg
• > 10 yrs - 1,200 mg

Question 6

how would you initially manage a pt with meningitis?

Answer 6

1. empirical antibiotic therapy (immediately after LP or straight away if LP delayed >30 mins): IV CEFTRIAXONE +/- ACYCLOVIR.
2. DEXAMETHASONE 8.3 mg every 6 hrs for 4 days (steroids reduce risk of hearing loss and neurological sequelae).
3. Supportive: fluids, analgesia, antipyretics…

Question 7

how would you adjust antibiotic Tx once causative MO identified?

Answer 7

• N. meningitidis: IV CEFTRIAXONE 7 days min.
• Group B streptococci: IV CEFOTAXIME 14 days min.
• Listeriosis: add IV amoxicillin
• Herpes simplex: acyclovir

Question 8

how can meningitis cause an acute adrenal crisis?

Answer 8

WATERHOUSE-FRIDERICHSEN SYNDROME: bilateral adrenal gland haemorrhage causing adrenal insfficiency