References for this Review were identified by searches of Medline and PubMed between 1969 and February, 2008, with the term “bacterial meningitis” in conjunction with “diagnosis”, “therapy” and “prevention”. Abstracts and reports from meetings were not included. The final reference list was generated on the basis of originality and relevance to the aims of the Review.
ReviewThe diagnosis and management of acute bacterial meningitis in resource-poor settings
Introduction
Acute bacterial meningitis is at least ten times more common in developing countries than in the rest of the world1 and is almost always fatal without treatment.2 Survival depends on accurate diagnosis and the early administration of antibiotics,3 neither of which is easy to achieve when resources are limited. Additional factors, such as advanced HIV infection, malnutrition, and antibiotic-resistant bacteria, complicate the management of the infected patient. For these reasons, acute bacterial meningitis presents an exceptional challenge to physicians working in resource-poor settings. We have focused this review on the common clinical problems that arise when a patient with acute bacterial meningitis presents to a doctor and we review the evidence available to resolve these problems in settings with limited resources.
Section snippets
Clinical features
The clinical features of acute bacterial meningitis usually develop over 24–48 hours but their nature varies according to the age of the patient. Panel 1 outlines the common symptoms and signs of bacterial meningitis in older children and adults. The triad of headache, neck stiffness, and photophobia is difficult to assess in young children and other features should be sought. Irritability, reduced conscious level, a bulging fontanel, poor feeding, cyanosis, “staring eyes”, and seizures outside
Blood tests
The microscopic search for malarial parasites is an important blood test in regions where malaria is endemic. The test has a negative predictive value greater than 95%,31 although this is commonly not appreciated.32 A negative blood film from a febrile patient should prompt a thorough search for an alternative diagnosis. In seriously ill children from regions where malaria is endemic, a blood film that is positive for malaria is hard to interpret, and analysis of the CSF is often needed to
Diagnostic prediction rules and algorithms
Many hospitals in low-income countries do not have culture facilities. Clinicians, therefore, rely heavily on clinical features and simple laboratory data to make a diagnosis. Several diagnostic rules have been proposed that use the clinical features at presentation to predict the diagnosis of bacterial meningitis4, 73, 74 or to distinguish pyogenic from other types of meningitis (table 1).42, 75, 76, 77, 78 However, only two such rules have been developed for resource-poor settings (table 2).
Choice of antibiotic therapy
Ceftriaxone has become affordable to many developing countries since its patent expired in 2005.79, 80 In 2007, WHO guidelines for the treatment of bacterial meningitis in Africa recommended ceftriaxone as first-line therapy.81 Nevertheless, penicillin (ampicillin/amoxicillin or benzylpenicillin) and chloramphenicol are still used in many developing countries. The authors of a recent systematic review and meta-analysis compared the efficacy of third-generation cephalosporins with conventional
Dexamethasone
Adjunctive corticosteroids have long been suggested for the treatment of bacterial meningitis, although evidence that confirms their beneficial effect has been hard to obtain. The authors of a European trial of 301 adults showed that dexamethasone significantly reduced death and neurological sequelae.102 Consequently, adjunctive corticosteroid therapy has been widely adopted in many high-income countries.87 Whether the same recommendations should apply to the developing world is uncertain. The
Fluid resuscitation
A patient with acute bacterial meningitis must first be examined for signs of hypovolaemia and for compensated or decompensated shock, which needs urgent treatment. Treatment guidelines are best developed for meningococcal disease,107 but septic shock is also common in pneumococcal and other meningitides, particularly when they present late.
Half of all children and a third of all adults that present with bacterial meningitis are hyponatraemic.108, 109 Until recently, the syndrome of
Prevention
Bacterial meningitis can be prevented by vaccination and by antibiotic chemoprophylaxis.113 The latter is reserved for localised outbreaks caused by N meningitidis and the aim is to eradicate nasopharyngeal colonisation and transmission. Ceftriaxone, rifampicin, and ciprofloxacin are the most effective antibiotics,113 although rifampicin resistance can develop quickly, and cases of fluoroquinolone-resistant N meningitidis have been reported.114, 115 Chemoprophylaxis is rarely used in
Conclusions
In resource-poor settings, the management of bacterial meningitis is particularly difficult because of factors such as late presentation of the disease, a wide differential diagnosis, and the limited range of diagnostic facilities and therapeutic options. Advances such as the use of diagnostic algorithms, urine dipsticks, and the wider accessibility to ceftriaxone have been made. In the broader context of development, further improvements in outcome from bacterial meningitis could be achieved
Search strategy and selection criteria
References (124)
- et al.
Diagnosis of acute bacterial meningitis in children at a district hospital in sub-Saharan Africa
Lancet
(2001) - et al.
Tuberculous meningitis: many questions, too few answers
Lancet Neurol
(2005) - et al.
Primary and opportunistic pathogens associated with meningitis in adults in Bangui, Central African Republic, in relation to human immunodeficiency virus serostatus
Int J Infect Dis
(2006) - et al.
The medical management of central nervous system infections in Uganda and the potential impact of an algorithm-based approach to improve outcomes
Int J Infect Dis
(2007) - et al.
Assessment of inpatient paediatric care in first referral level hospitals in 13 districts in Kenya
Lancet
(2004) - et al.
Diagnosis of adult tuberculous meningitis by use of clinical and laboratory features
Lancet
(2002) - et al.
Meningococcal meningitis with ‘normal’ cerebrospinal fluid
J Infect
(1994) - et al.
Cryptococcal meningitis in Lilongwe and Blantyre, Malawi
J Infect
(1994) - et al.
Rapid diagnosis of bacterial meningitis with reagent strips
Lancet
(1995) - et al.
Does the use of urinary reagent strip tests improve the bedside diagnosis of meningitis?
Trans R Soc Trop Med Hyg
(1999)