Which antibiotics and vaccines should be used for meningococcal disease?
A local GP has telephoned to arrange for a four-year-old boy to be admitted to the paediatric ward with suspected meningitis. The child has had a fever, loss of appetite and nausea since yesterday but in the past four hours his condition has deteriorated.
He now has photophobia and a severe headache, and he has become slightly disorientated.
Examination confirms that he is febrile. He has neck stiffness but there is no skin rash. There is no previous medical history of note and childhood vaccinations are all up to date. In the past three months, he has not received any antibacterials or travelled abroad. He lives with his father, mother and two-year-old sister, all of whom are well.
Should the GP give the boy benzylpenicillin before he is brought in to hospital?According to Table 1, section 5.1, BNFC 2011-2012 (p248), benzylpenicillin should only be given to a child with suspected bacterial meningitis without non-blanching rash if he or she cannot be transferred to hospital urgently. The rationale for this is that bacterial meningitis without non-blanching rash progresses less rapidly than meningococcal septicaemia.
On arrival at the hospital a series of investigations are undertaken. His blood pressure (108/64mmHg) and respiratory rate (26 breaths per minute) are within normal limits.
• Peripheral neutrophil count = 22.0x109/L (1.5-7.5x109/L)
• Serum C-reactive protein = 70mg/L (<10mg/L)
• Blood glucose = 4.2mmol/L
He is assessed to exclude the presence of raised intracranial pressure, and a lumbar puncture is performed to remove a sample of cerebral spinal fluid (CSF).
Examination of the CSF shows:
• 240 white blood cells/mm3 (<5 cells/mm3)
• 90 per cent neutrophils
• Protein 6.2g/L (<0.4g/L)
• Glucose 0.9mmol/L
A high white cell count with mostly neutrophils in the CSF, a CSF protein concentration greater than 1g/L, and a CSF glucose concentration less than 50 per cent of the plasma-glucose concentration is consistent with bacterial meningitis.
No organisms are seen on a Gram-stained smear of the CSF. The sample is cultured and a sample is also sent to the reference laboratory to test for Neisseria meningitidis (meningococcus) by polymerase chain reaction (PCR).
What initial antibacterial therapy should be started in hospital? Table 1 also recommends that bacterial meningitis of unknown cause in a four-year-old should be treated with either cefotaxime or ceftriaxone; however, ceftriaxone should not be given simultaneously with infusion fluids containing calcium.
It is not necessary to add vancomycin because the child has no history in the past three months of prolonged or multiple use of other antibacterials or of having travelled to areas outside the UK with highly penicillin- and cephalosporin-resistant pneumococci. If necessary, antibacterial therapy can be adjusted further when the results of culture and sensitivity testing are available.
Should this child also receive dexamethasone? Adjunctive corticosteroids reduce the risk of severe hearing loss and long-term neurological sequelae following bacterial meningitis. According to Table 1, dexamethasone can be considered in this case because there are no signs of meningococcal septicaemia or septic shock, the patient is not immunocompromised, and the meningitis is not related to surgery.
Dexamethasone should preferably be started before or with the first dose of antibacterial, but no later than 12 hours after starting the antibacterial. Dexamethasone is indicated for this child because lumbar puncture reveals a raised CSF white blood cell count with a protein concentration greater than 1g/L.
The next day, there is no growth in the cultured CSF sample. However, later that day the reference laboratory telephones with the result of the PCR: positive for N meningitidis serogroup B.
What is the suggested duration of antibacterial therapy for meningococcal meningitis? For meningococcal meningitis, Table 1 suggests a course of benzylpenicillin, cefotaxime or ceftriaxone, for a total of seven days.
Bacterial meningitis is a notifiable disease. N meningitidis in particular has potential to cause large epidemics. The local public health service is notified about this case within 24 hours of the diagnosis.
What antibacterial prophylaxis should be offered to the index case and his close contacts? Antibacterial prophylaxis should be given to close contacts as soon as possible (ideally within 24 hours) after diagnosis of the index case. Table 2 (section 5.1, BNFC 2011-2012) recommends ciprofloxacin, rifampicin or ceftriaxone for prophylaxis against meningococcal disease. A single dose of ciprofloxacin is preferred in those over one month old, so long as there are no contraindications.
In order to eradicate carriage, the boy should also be given antibacterial prophylaxis as soon as he is able to swallow, but before he is discharged from hospital.
Antibacterial prophylaxis is not necessary for an index case if the infection is treated with ceftriaxone because this antibiotic has been shown to eliminate the bacteria from the nasal passages.
Does meningococcal vaccine have a role in managing the index case and his contacts? Although vaccines are available against other serogroups of N meningitides (A, C, W135, and Y), they confer no protection against serogroup B disease. However, any case of meningitis provides an opportunity to check the meningococcal group C conjugate vaccination status of the index case and contacts and to ensure that they have been fully immunised according to the UK schedule.
The prescribing notes on meningococcal vaccines in section 14.4 BNFC 2011-2012, recommend that meningococcal group C conjugate vaccine is given to anyone under 25 years of age who has not been vaccinated previously with this vaccine; those over one year of age should receive a single dose.
The boy makes a good recovery and six months later the family are planning to travel to Saudi Arabia for the umra pilgrimage.
Which meningococcal vaccine will you recommend for this family? Recurrent meningococcal disease with the same serogroup is rare. However, the child will still be susceptible to meningococcal disease caused by other serogroups that predominate in other parts of the world.
Proof of vaccination with the tetravalent meningococcal vaccine is required for those travelling to Saudi Arabia during the haj and umra pilgrimages (where outbreaks of serogroup A and W135 meningococcal infection have occurred).
According to the prescribing notes on meningococcal vaccines (section 14.4,
BNFC 2011-2012), adults and children travelling to countries at risk should be immunised with the tetravalent meningococcal A, C, W135, and Y conjugate vaccine (Menveo). If an individual has recently received meningococcal group C conjugate vaccine, an interval of at least four weeks should be allowed before administration of the tetravalent conjugate vaccine.
Although the duration of protection has not been established, the tetravalent meningococcal conjugate vaccine is likely to provide longer-lasting protection than the tetravalent unconjugated meningococcal polysaccharide vaccine (ACWY Vax).
Menveo is not licensed for use in children under 11 years of age but its use in this age group is recommended by the Joint Committee on Vaccination and Immunisation.
Based on a case study from the BNF/BNFC e-newsletter, July 2011, available at http://bnfc.org
Citation: The Pharmaceutical Journal URI: 11087012
Recommended from Pharmaceutical Press