Bacterial meningitis
Bacterial meningitis is defined as "bacterial infections of the leptomeninges and subarachnoid space, frequently involving the cerebral cortex, cranial nerves, cerebral blood vessels, spinal cord, and nerve roots. The type of causative organism varies with age and clinical status (e.g., post-operative, immunodeficient, or post-traumatic states). Clinical manifestations include the acute onset of fever, stiff neck, altered mentation, seizures, and focal neurologic deficits. Death may occur within 24 hours of disease onset. Pathologic features include a purulent exudate in the subarachnoid space, and diffuse inflammation of neural and vascular structures."[1][2]
Treatment
Antibiotics
Corticosteroids
Corticosteroids probably benefit patients with meningitis if they are proven to have a bacterial etiology, especially if they have a Glasgow Coma Scale of less than 12 or are infected by streptococcus pneumonia.
One randomized controlled trial of 301 patients from the United States (76 were infected with streptococcus pneumonia) found benefit when:[3]
- 10 mg of dexamethasone is given every six hours for four days starting 15 to 20 minutes before antibiotics
- patients had either had an initial Glasgow Coma Scale of less than 12 or were infected by streptococcus pneumonia
However, a subsequent randomized controlled trial of 465 patients from Africa (277 were infected with streptococcus pneumonia) no benefit was found in any group - including those patients infected with streptococcus pneumonia. [4] This study did not analyze by Glasgow Coma Scale.
A third randomized controlled trial of 435 patients from Vietnam found benefit when:[5]
- Dexamethasone 0.4 mg per kilogram of body weight every 12 hours for 4 days (about half received this before starting antibiotics)
- Patients with confirmed bacterial meningitis
The underlying prevalence of human immunodeficiency virus may explain the contradicting results. Although none of the studies explicitly excluded patients with HIV, in the American study (which showed benefit) patients were excluded if they "had a history of active tuberculosis or fungal infection". Whereas in the African study (which showed no benefit), 90% of the patients were positive for HIV. In the Vietnamese study, which showed some benefit, only 1% of patients had HIV.
References
- ↑ National Library of Medicine. Bacterial meningitis. Retrieved on 2008-01-04.
- ↑ van de Beek D, de Gans J, Tunkel AR, Wijdicks EF (2006). "Community-acquired bacterial meningitis in adults". N. Engl. J. Med. 354 (1): 44–53. DOI:10.1056/NEJMra052116. PMID 16394301. Research Blogging.
- ↑ de Gans J, van de Beek D (2002). "Dexamethasone in adults with bacterial meningitis". N. Engl. J. Med. 347 (20): 1549–56. DOI:10.1056/NEJMoa021334. PMID 12432041. Research Blogging.
- ↑ Scarborough M, Gordon SB, Whitty CJ, et al (2007). "Corticosteroids for bacterial meningitis in adults in sub-Saharan Africa". N. Engl. J. Med. 357 (24): 2441–50. DOI:10.1056/NEJMoa065711. PMID 18077809. Research Blogging.
- ↑ Nguyen TH, Tran TH, Thwaites G, et al (2007). "Dexamethasone in Vietnamese adolescents and adults with bacterial meningitis". N. Engl. J. Med. 357 (24): 2431–40. DOI:10.1056/NEJMoa070852. PMID 18077808. Research Blogging.