Infectious Diseases: Meningitis

Question 1

Outline the pathophysiology of meningitis.

Answer 1

Infection/inflam of the meninges

Question 2

Outline the aetiology of meningitis.

Answer 2

0-3m = group B strep, e.coli, listeria

3m-6y = strep pneumonia, Neisseria meningitidis, H.influenza

6-60y = strep pneumonia, Neisseria meningitidis

> 60y = strep pneumonia, Neisseria meningitidis, listeria

Question 3

What are the signs and symptoms of meningitis?

Answer 3

Early:

• Headache
• Leg pains
• Cold hands/feet
• Abnormal skin colour
• Fever

Later:

• Meningism = stiff neck, photophobia, Kernigs sign (pain + resistance on passive knee extension with hip fully flexed)
• Decreased conscious level, coma
• Seizures
• Petechial rash - non-blanching
• Sepsis = slow cap refill, decreased BP, increased temp, increased pulse

Question 4

How would you investigate meningitis?

Answer 4

Bloods = FBC, U+Es, LTF, glucose, coag (on LP don’t want the pt to bleed)

Blood cultures, throat swabs, rectal swabs

LP (do not perform in RICP) = CSF for C+S

CT head

CXR

VBG

Ophthalmoscopy

Question 5

How would you manage meningitis?

Answer 5

A-E assessment

Dexamethasone 4-10mg/6h IV = reduced RICP/inflam

Start Abx

• <3m = IV cefotaxime + oral amoxicillin
• 3m-50y = IV cefotaxime
• > 50y = IV cefotaxime + oral amoxicillin

IV fluids

Isolate for 1st 24h

Careful monitoring

Household/close contacts = rifampicin or oral ciprofloxacin

Question 6

What are the complications of meningitis?

Answer 6

Encephalitis

Residual paralysis/focal neurology

Hearing loss

Cerebral abscess

Sepsis - DIC

Death

Question 7

What is a notifiable disease?

Answer 7

Suspected case/diagnosed case that needs to be reported = fill out form to notify that proper officer of local health protection team (HPT)

Question 8

Which of the following is NOT a notifiable disease?

A. Botulism 
B. HIV 
C. Legionnaire’s disease 
D. Measles 
E. Tuberculosis

Answer 8

HIV

Question 9

What are the different types of meningitis? What organisms are commonly involved?

Answer 9

Bacterial = meningococcal, pneumococcal

Viral = enteroviruses, herpes simplex, HIV, mumps

Parasitic = microscopic amoeba

Fungal = cryptococcus

Non-infectious = RA, SLE

Question 10

How can infection spread to the meninges?

Answer 10

Haematogenous spread

Direct = surgery, open skull fracture

Question 11

What are the risk factors for meningitis?

Answer 11

Immunocompromised = listeria most common MO

Sinusitis

Mastoiditis

Pneumonia - haematogenous spread

Skull fracture

Question 12

Outline the signs you would be looking for in order to identify a source of infection regarding meningitis

Answer 12

Cold sores/genital vesicles = HSV

LNs, dermatitis, candidiasis, uveitis = HIV

Bleeding +/- red eye = leptospirosis

Parotid swelling = mumps

Sore throat, jaundice, nodes = glandular fever

Splenectomy scar = immunodef

Question 13

What are the signs of RICP?

Answer 13

CT head (midline shift, tentorial herniation)

Changes in consciousness

Optic disk swelling

Severe vomiting