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.
- Respiratory support techniques including tracheal intubation, mechanical ventilation, continuous positive airways pressure (CPAP) or biphasic positive airways pressure, or possibly extracorporeal oxygenation techniques
- 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
- Inotropic/vasopressor support
- 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.;
- Renal replacement therapy.
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)
- 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
Investigations
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.
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 | 101-104Neutrophils | Positive | Positive | High | <70% of blood level |
Tuberculous | 101-103 Lymphocytes | Positive or negative | Negative | High or very high | <60% of blood level |
- If the diagnosis is in doubt, give antibiotics microbiology team review at 48°)
- In partially treated bacterial meningitis lymphocytes may be predominate. Protein is often high
- 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
- 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 | Conversation | Localises to pain | |
4 | Spontaneous | Sentences | Withdrawal to pain |
3 | To speech | Words | Abnormal flexion to pain |
2 | Eyes open to pain | Sounds | Extends to pain |
1 | No eye opening | Nothing | 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:-
- Family contacts
- Kissing contacts
- Children under five who have attended a party at which a child was incubating the infection
- Children under five in the same crèche (not school) class
- 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
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
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.
Links
- Ref 1De Gans J, Van de Beek D. Dexamethasone in adults with bacterial meningitis. NEJM 2002;347(20):1594
- Working Group on Bacterial Meningitis - DoHC 1999 Local copy