Adult meningitis



Important points

  • Neck stiffness is absent in 18% of patients.
  • Skin rashes are significantly more common in meningococcal than in pneumococcal meningitis. Notably the initial rash in meningococcal infection may be non-specific and up to 50% of patients with meningococcal meningitis do not have a rash on first presentation.
  • Fundoscopic abnormalities are unusual.
  • Papilloedema, although an uncommon manifestation of rapid onset raised intra-cranial pressure is a definite contra-indication to lumbar puncture without prior CT
  • Cranial nerve palsies (notably affecting nerves III, IV, VI and VII) and focal neurological signs occur in 10-30% of cases. They may be an early sign in Listeria monocytogenes meningitis.
  • Abnormal mental states found in 85% of patients (may be only sign in the elderly).
  • Seizures occur in about 30%. Pneumococcal more than meningococcal.
  • Tuberculous meningitis may present with an abrupt onset of meningeal signs but more commonly presents as a slow onset of vague illness with fever, developing headache and mental state changes. In some patients fever is minimal. 16 - 50% have evidence of TB outside the CNS (pulmonary or miliary). Discuss cases with the duty microbiology consultant. A viral prodrome with headache, confusion and less meningitic features is suggestive of viral encephalitis. Discuss with duty consultant virologist.

Table III Clinical symptoms and signs in 132 adults with community acquired bacterial meningitis in Iceland.

  • Fever (>30ºC) on admission 97%
  • Fever > one day 12%
  • Neck stiffness 82%
  • Abnormal mental states 66%
    • Confused or lethargic 45%
    • Only responsive to pain 8%
    • Unresponsive to pain 11%
  • Triad of fever, neck stiffness and Impaired consciousness 51%
  • Seizures 10% 
  • Rash 52%
    • petechial, purpuric or maculopapular

Management algorithm


Resus Management

Airway Management

  • Consider RSI in all patients with airway compromise
  • Contact the ICU Registrar at an early stage

Breathing Management

Early assisted ventilation is required if there is:

  • Hypoxaemia persisting despite administration of high flow oxygen and/ or
  • Hypercapnia and/or
  • A vulnerable airway and/or
  • Prolonged or uncontrolled seizures and/or
  • Heart failure arising from myocardial depression
  • Clinical signs of raised intracranial pressure
  • A declining conscious level

Circulatory Management

Treatment aims are adequate cardiac output/oxygen delivery and therefore organ perfusion.

  • Patients should be kept euvolaemic (not fluid restricted reduce cerebral oedema).
  • Fluid resuscitation with CVP response to fluid.
  • Consider inotropes early, if no response to fluid.
  • Swan to monitor cardiac output 
  • Beware Coagulopathy  (DIC & thrombocytopenia). Treatment is given if coagulopathy is severe or symptomatic, or prophylactically prior to invasive procedures.

Disability (Neurological) Management

  • Patients with obvious significant raised intra-cranial pressure should be electively intubated and given appropriate therapy to reduce ICP.
  • Routine use of intracranial pressure monitoring is not recommended. It should be considered in individual patients with evidence of markedly raised intracranial pressure such as papilloedema or pupillary signs.
  • Mannitol should be considered in patients with impaired conscious levels, lateralising neurological signs, markedly raised opening pressure at lumbar puncture or evidence of cerebral oedema on brain scanning
  • Patients with seizures requiring mechanical ventilation and neuromuscular paralysis should have continuous electroencephalogram monitoring to exclude ongoing seizure activity.
  • Nurse patients head up at 30°
  • Avoid neck lines

Renal Management

Renal replacement therapy should be considered (WP) if there is:

  • Persisting oliguria despite restoration of adequate cardiac output, or
  • Hyperkalaemia, or
  • Severe metabolic acidosis, or
  • Severe metabolic acidosis secondary to renal failure, or
  • Fluid overload, or
  • Need for intravascular compartment space for administration of drugs or nutrition.

Intensive care units should be involved early.

The following patients require intensive care unit facilities and expertise:

  • Those with central nervous system depression.
  • Those with airway or respiratory instability (? protected airway / hypoxaemia)
  • Those with cardiovascular instability with hypotension not responding promptly to fluid challenges, oliguria persisting for more than 2-3 h or increasing metabolic acidosis
  • Those with neurological impairment and/or seizures;

There are five life support interventions which are best carried out in an intensive care unit.

  1. Respiratory support techniques including tracheal intubation, mechanical ventilation, continuous positive airways pressure (CPAP) or biphasic positive airways pressure, or possibly extracorporeal oxygenation techniques.
  2. Specialised cardiovascular monitoring possibly including monitoring of cardiac output, blood gas, studies, peripheral artery cannulation for arterial blood gas analysis and continuous monitoring for arterial blood gas analysis, and continuous monitoring of blood pressure or for other haemodynamic monitoring techniques, e.g. oesophageal Doppler ultrasounography or echocardiography.
  3. Inotropic/vasopressor support.
  4. Specialised neurological monitoring including ICP monitoring, jugular venous bulb catheterisation for monitoring of jugular venous bulb saturation, cerebral venous lactate measurement, middle cerebral artery Doppler blood flow measurement, and continuous EEG monitoring.;
  5. Renal replacement therapy.

Back to Management algorithm

Antimicrobial Therapy

  • All adult patients should receive their first dose of 2G Ceftriaxone Bd.
  • Add vancomycin intravenously 500 mg 6 hourly if 
    • LP to be delayed in patients without a typical meningococcal rash OR
    • Patient from an area where penicillin resistant pneumococci common (Spain e.g.)
  • For adults aged over 50 years or immunocompromised, add IV ampicillin PLUS Gentamicin (listeria) (Antibiotic guidelines page)
  • Discuss with the duty microbiology consultant.
  • With a clear history of anaphylaxis to beta-lactams contact the microbiologist who may suggest  
    • chloramphenicol intravenously 25 mg/kg 6 hourly plus 
    • vancomycin iv 500 mg 6 hourly. (for penicillin/ chloramphenicol resistant pneumococci) plus
    • Additional co-trimoxazole should be given in those over 50 years young.

For all patients with meningitis (not septicaemia) give dexamethasone 10 mg iv 6 hourly before or with antibiotics (Ref 1)


Control of Infection Action: to be taken after admitting or seeing a patient with suspect/confirmed Meningococcal Meningitis or Septicaemia in the ED

  • Patient should be admitted to a side-room and barrier nursed
  • Contact the Hospital Control of Infection team. (See Infection control Manual)
  • Arrange for treatment of patient and prophylaxis of appropriate contacts
  • Contact Community Health Service appropriate to county of residence of your patient

Further bloods/swabs

All patients

  • Blood Culture
  • Throat swab (or petechiae aspirate)
  • EDTA blood sample for meningococcal PCR
  • Clotted blood sample for viral serology

Additional specimens

  • Throat swab (viral)
  • Faeces for virology
  • CSF for bacteriology
  • CSF for virology (please specify if encephalitis or meningitis suspected)

An EDTA specimen should be taken at the time of first blood sampling so that it can be sent for polymerase chain reaction studies if needed.
A baseline clotted blood sample for serological testing should be collected within 24 h.

Back to Management algorithm


Contacts and admission

  • Close contacts should be given prophylaxis if meningococcal infection is likely.
  • The consultant responsible for the patient's care should be informed of the admission as soon as is reasonable.
  • If bacterial meningitis is possible the relevant Consultant in Communicable Disease control should be contacted without delay. Prophylaxis in the community should not normally be undertaken by admitting clinicians.

Contraindications to lumbar puncture

Signs of raised ICP

  • Changing level of consciousness
  • Focal neurological signs
  • Severe mental impairment

Cardiovascular compromise

  • Impaired peripheral perfusion, Hypotension

Respiratory compromise

  • Tachypnoea, abnormal breathing pattern
  • Hypoxia

CSF findings in acute meningitis

 

Cells

Gram stain

Bacterial antigen detection

Protein g/l
(normal 0.1-0.4)

Glucose mmol/l
(normal 2.3-4.5)

Viral
101-103 Lymphocytes
Negative
Negative
Normal or slightly high
Usually normal
Bacterial
101-104 Neutrophils
Positive
Positive
High
<70% of blood level
Tuberculous
101-10 Lymphocytes
Positive or negative
Negative
High or very high
<60% of blood level
  1. If the diagnosis is in doubt, give antibiotics microbiology team review at 48°)
  2. In partially treated bacterial meningitis lymphocytes may be predominate. Protein is often high.
  3. The CSF is usually normal in meningococcal septicaemia and it may be microscopically and biochemically normal in 5-10% of patients in the early stages of meningococcal meningitis subsequently confirmed by culture of the same specimen
  4. Microbacterium tuberculosis is seen in the initial CSF in only about 40% of samples from patients who have tuberculous meningitis. Initial suspicion may have to rely on the finding of low cerebrospinal glucose level and a high protein level in patients with a lymphocytic meningitis. However, in early tuberculous meningitis the CSF may show a polymorphonuclear response and even the protein level may occasionally be normal. Consult with the on call microbiologist.

Prognosis

There is a good correlation between the GCS and clinical outcome.

In one review:

  • 80% of those with GCS > 12 had a good neurological outcome
  • 88% with a GCS < 8 had a poor outcome.

Adverse prognosis

  • Presence of a haemorrhagic diathesis.
  • Focal neurological signs.
  • Deteriorating conscious level.
  • Multi-system organ failure.
  • A rapidly developing rash.
  • Age 60 years or more.

Glasgow Coma Score

Score

Eye Opening

Verbal

Motor

6

Obeys commands

5

Speech orientated , localises to pain

4

Spontaneous eye opening

Confused speech

Withdrawal to pain

3

Eye open to speech

Incoherent words

Abnormal flexion to pain

2

Eyes open to pain

Only sounds

Extends to pain

1

No eye opening

No sounds

No movements


Prophylaxis

Meningococcal meningitis is an uncommon but sometimes fatal infection. Incidence in the UK is about 0.9 cases per 100,000 population per annum. During outbreaks the rate can rise tenfold. It is quite common for individuals to carry meningococci in their throats and remain well. 10% to 20% of the population may do so at any given moment. During so-called outbreaks situations carrier rates can rise to over 50%. About 1% of those carried are associated with risk of development of clinical meningitis. The body rapidly becomes immune to even these strains so that the risk of clinical meningitis seems to be associated with the time just after one of these dangerous strains has been picked up, rather than during the entire duration of carriage. Transmission of dangerous strains of meningococci to contacts of a case can occur. Thus risk of clinical disease in a contact is 500-800 times greater than in the normal unexposed population, at round 4.2 per thousand. The organisms are usually spread by direct transfer in droplets of saliva or pharyngeal secretion from one person to another, by direct physical contact or through the air. This risk is entirely restricted to close contacts. These include persons living in the same household and "kissing" contacts. In order to prevent such people from developing meningitis, prophylaxis with rifampicin is usually given. This will protect them and will also, by clearing carriage of the dangerous strain in these people, prevent the possibility of their passing the strain on to a third party at some later date. Prophylaxis is recommended for:-

  1. Family contacts.
  2. Kissing contacts.
  3. Children under five who have attended a party at which a child was incubating the infection.
  4. Children under five in the same crèche (not school) class.
  5. Health care workers only recommended chemoprophylaxis if “mouth or nose is directly exposed to respiratory droplets and/or secretions from a case of meningococcal disease". This type of exposure may occur during procedures, such as resuscitation or airways management, when a mask has not been worn, with 1 metre of the case.” We would not recommend chemo for ambulance staff, unless fulfil this criteria.

Prophylactic Drugs : Either rifampicin or ciprofloxacin

Back to Management algorithm


Notes on rifampicin

  • May reduce effectiveness of contraceptive pill
  • Soft contact lenses may be permanently damaged
  • May cause pink/orange staining of saliva, tears ant urine
  • Not recommended in pregnancy or breast feeding mothers
  • See eBNF for interactions with other medications
  • Side effects include : anorexia, vomiting, diarrhoea, rash, jaundice, itch, 'flu like temperature
Dose of Rifampicin
Prophylactic dose in meningococcus
(syrup contains 100 mg / 5 ml)
0 - 2 months 20 mg (1 ml syrup) Bd for 2 days
3 - 11 months 40 mg (2 ml syrup) Bd for 2 days
1 - 5 years 150 mg (7.5 ml syrup) Bd for 2 days
6 - 12 years 300 mg (as capsule) Bd for 2 days
Adults 600 mg Bd for 2 days
If rifampicin may be required, please ID registrar

Prophylaxis drugs - CUH

Meningitis prophylaxis drugs (plus info) are kept in a box in the DDA press in the clean utility room. These are supplied by public health but it includes rifampicin liquid & capsules. These may be supplied to family contacts, staff etc out of hours.



Content by Dr Íomhar O' Sullivan 26/03/2001. Reviewed by Dr ÍOS 01/07/2003, 08/01/2005, 26/02/2007. Last review Dr ÍOS 1/12/17