Infection - Meningitis Flashcards
Meningococcal septicaemia is the cause of the classic “non-blanching rash” that everybody worries about. What does this rash indicate?
This rash indicates the infection has caused disseminated intravascular coagulopathy (DIC) and subcutaneous haemorrhages.
What does meningococcal septicaemia refer to?
Meningococcal septicaemia refers to the meningococcus bacterial infection in the bloodstream.
What does meningococcal meningitis refer to?
Meningococcal meningitis is when the bacteria is infecting the meninges and the cerebrospinal fluid around the brain and spinal cord.
What are the most common causes of bacterial meningitis in children and adults?
Neisseria meningitidis (meningococcus) and Streptococcus pneumoniae (pneumococcus)
What is the most common cause of bacterial meningitis in neonates?
Group B Streptococcus (GBS). GBS is usually contracted during birth from GBS bacteria that often live harmlessly in the mother’s vagina.
Typical symptoms of meningitis
- fever
- neck stiffness
- vomiting
- headache
- photophobia
- altered consciousness
- seizures
- meningococcal septicaemia can present with a non-blanching rash (other causes of bacterial meningitis do not usually cause the non-blanching rash)
How do neonates and babies present with meningitis?
Neonates and babies can present with very non-specific signs and symptoms, such as hypotonia, poor feeding, lethargy, hypothermia and a bulging fontanelle.
NICE recommend a lumbar puncture as part of the investigations for all children:
- Under 1 months presenting with fever
- 1 to 3 months with fever and are unwell
- Under 1 years with unexplained fever and other features of serious illness
There are two special tests you can perform to look for meningeal irritation:
Kernig’s test involves lying the patient on their back, flexing one hip and knee to 90 degrees and then slowly straightening the knee whilst keeping the hip flexed at 90 degrees. This creates a slight stretch in the meninges. Where there is meningitis it will produce spinal pain or resistance to movement.
Brudzinski’s test involves lying the patient flat on their back and gently using your hands to lift their head and neck off the bed and flex their chin to their chest. In a positive test this causes the patient to involuntarily flex their hips and knees.
Management of bacterial meningitis in a child in the community:
Children seen in the primary care setting with suspected meningitis AND a non blanching rash should receive an urgent stat injection (IM or IV) of benzylpenicillin prior to transfer to hospital as time is so important
In a hospital setting what tests would ideally be done before starting antibiotic therapy for meningitis?
Ideally a blood culture and a lumbar puncture for cerebrospinal fluid (CSF) should be performed prior to starting antibiotics, however if the patient is acutely unwell antibiotics should not be delayed.
What test should be done if meningococcal disease is suspected?
Send bloods for meningococcal PCR. This tests directly for the meningococcal DNA. It can give a result quicker than blood culture depending on local services, and will still be positive after the bacteria has been treated with antibiotics.
Management of bacterial meningitis in a hospital
- Typical antibiotics are:
- Under 3 months – cefotaxime plus amoxicillin (the amoxicillin is to cover listeria contracted during pregnancy)
- Above 3 months – ceftriaxone
Vancomycin should be added to these antibiotics if there is a risk of penicillin resistant pneumococcal infection, for example recent foreign travel or prolonged antibiotic exposure.
Steroids are also used in bacterial meningitis to reduce the frequency and severity of hearing loss and neurological damage. Dexamethasone is given 4 times daily for 4 days to children over 3 months if the lumbar puncture is suggestive of bacterial meningitis.
Bacteria meningitis and meningococcal infection are notifiable diseases, what does this mean?
Public health needs to be informed of all cases
Who is given post exposure prophylaxis for bacterial meningitis and what is given?
This risk is highest for people that have had close prolonged contact within the 7 days prior to the onset of the illness. The risk decreases 7 days after exposure. Therefore, if no symptoms have developed 7 days after exposure they are unlikely to develop the illness.
The usual antibiotic choice for this is a single dose of ciprofloxacin. It should be given as soon as possible and ideally within 24 hours of the initial diagnosis.
