Meningitis pneumococcal

Penicillin is the dmg of choice for the treatment of group B streptococcal, meningococcal and pneumococcal infections but, as discussed earlier, CSF concentrations of penicillin are significantly influenced by the intensity of the inflammatoiy response. To achieve therapeutic concentrations within the CSF, high dosages are required, and in the case of pneumococcal meningitis should be continued for 10-14 days. 

Development of resistance to P -lactam antibiotics, including penicillins and cephalosporins, has significantly impacted the management of bacterial meningitis. Approximately 17% of United States pneumococcal CSF isolates are resistant to penicillin, and 3.5% of CSF isolates are resistant to cephalosporins.26 The Clinical and Laboratory Standards Institute (CLSI) has set a lower ceftriaxone susceptibility breakpoint for pneumococcal CSF isolates (1 mg/L) than for isolates from non-CNS sites (2 mg/L). Increasing pneumococcal resistance to penicillin G... 

High-dose penicillin G traditionally has been the drug of choice for the treatment of pneumococcal meningitis. However, due to increases in pneumococcal resistance, the preferred empirical treatment now includes a third-generation cephalosporin in combination with vancomycin.13 All CSF isolates should be tested for penicillin and cephalosporin resistance by methods endorsed by the CLSI. Once in vitro sensitivity results are known, therapy may be tailored (Table 67-3). Patients with a history of type I penicillin allergy or cephalosporin allergy may be treated with vancomycin. Treatment should be continued for 10 to 14 days, after which no further maintenance therapy is required. Antimicrobial prophylaxis is not indicated for close contacts. 

There is concern regarding administration of dexamethasone to patients with pneumococcal meningitis caused by penicillin- or cephalosporin-resistant strains, for which vancomycin would be required. Animal models indicate that concurrent steroid use reduces vancomycin penetration into the CSF by 42% to 77% and delays CSF sterilization due to reduction in the inflammatory response.23 Treatment failures have been reported in adults with resistant pneumococcal meningitis who were treated with dexamethasone, but the risk-benefit of using dexamethasone in these patients cannot be defined at this time. Animal models indicate a benefit of adding rifampin in patients with resistant pneumococcal meningitis whenever dexamethasone is used.21,23... 

Streptococcus pneumoniae is the most common bacterial cause of community-acquired respiratory tract infections. S. pneumoniae causes approximately 3000 cases of meningitis, 50,000 cases of bacteremia, 500,000 cases of pneumonia, and over 1 million cases of otitis media each year. The increasing prevalence of drug-resistant S. pneumoniae has highlighted the need to prevent infection through vaccination. Both licensed pneumococcal vaccines are highly effective in preventing disease from the common S. pneumoniae serotypes that cause human disease. 

Kozar, M. Krahmer, M. Fox, A. Gray, B. M. Failure to detect muramic acid in normal rat tissues but detection in cerebrospinal fluid from patients with pneumococcal meningitis. Infect. Immun. 2000, 68, 4688 1698. 

Purpuric and petechial skin lesions typically indicate meningococcal involvement, although the lesions may be present with H. influenzae meningitis. Rashes rarely occur with pneumococcal meningitis. 

S. pneumoniae is the leading cause of meningitis in adults. Pneumococcal meningitis occurs in the very young (less than 2 years of age) and the very old. 

The Gram-positive bacterium Streptococcus pneumoniae is an important cause of respiratory tract infections, bacteremia, and meningitis. In this strain, the cell wall anchored pneumococcal surface protein A (PspA) has been demonstrated to bind lactoferrin [181]. PspA and closely related proteins in a variety of pneumococcal isolates are most likely involved in the sequestration of iron from lactoferrins, and finally contribute to the virulence of these bacteria. However, the means by which the pneumococcus acquires iron at the mucosal surface during invasive infection is not well understood at the molecular level [182],... 

In most cases one week of i.v. penicillin is adequate for meningococal meningitis. Ten to 14 days is recommended for pneumococcal meningitis. Two to 3 weeks for Listeria and group B streptococcal meningitis and 3 weeks is necessary for gramnegative meningitis. 

McMaster P et al. The emergence of resistant pneumococcal meningitis implications for empiric therapy. Arch Dis Child 2002 87 207-210. 

Salmonella and Haemophilus infections and meningococcal and pneumococcal meningitis. 

See footnote 3 in Table 51-2 for guidelines on the treatment of penicillin-resistant pneumococcal meningitis. 

There are few clinically relevant examples of antimicrobial antagonism. The most striking example was reported in a study of patients with pneumococcal meningitis. Patients who were treated with the combination of penicillin and chlortetracycline had a mortality rate of 79% compared with a mortality rate of 21% in patients who received penicillin monotherapy (illustrating the first mechanism set forth below). 

Meningococcal disease (purulent meningitis) commonly occurs in children, but is also observed in adults. Without antibiotic treatment, the mortality rate is high (85%), and, even with this treatment, cured patients can suffer serious and permanent neurological deficiencies.165 These facts, together with the emergence of antibiotic-resistant strains,8 prompted the rapid development of a commercial vaccine. This vaccine was developed almost simultaneously with the pneumococcal vaccine. 

Health Protection Agency (UK) (2005b). Numbers of laboratory confirmed pneumococcal meningitis cases in England and Wales, 1996-2005. Available at http // www.hpa.org.uk/webw/HPAweb HPAwebStandard/HPAweb C/1195733815884 p=1203409671918cases.htm [Accessed 3 July 2008],... 

Randomised clinical trials have demonstrated a significant beneficial effect of dexamethasone on mortality and morbidity in pneumococcal meningitis, although no benefit was seen for patients with meningococcal meningitis. Steroid treatment is now recommended routinely with or before the first dose of antibiotics, beyond which time dexamethasone begins to lose its effectiveness (van de Beek et al., 2004). 

The duration of therapy for meningococcal meningitis is at least 5 days (usually 7 days), 10-14 days for pneumococcal meningitis and at least 10 days for H. influenzae meningitis. Steroid therapy should continue for 4 days. 

Lorenzl S, Kodel U, Frei K, Pfister HW (1996) Effect of the bradykinin B2 receptor antagonist Hoel40 in experimental pneumococcal meningitis in the rat. Eur J Pharmacol 308 335-341 Lumenta DB, Plesnila N, Klasner B, Baethmann A, Pruneau D, Schmid-Elsaesser R, Zausinger S (2006) Neuroprotective effects of a postischemic treatment with a bradykinin B2 receptor antagonist in a rat model of temporary focal cerebral ischemia. Brain Res 1069 227-234 Mac Donald CL, Dikranian K, Bayly P, Holtzman D, Brody D (2(X)7) Diffusion tensor imaging reliably detects experimental traumatic axonal injury and indicates approximate time of injury. J Neurosci 27 11869-11876... 

Knowledge of the likely pathogens (and their current local susceptibility rates to antimicrobials) in the clinical situation. Thus cephalexin may be a reasonable first choice for lower urinary tract infection (coliform organisms — depending on the prevalence of resistance locally), and benzylpenicillin for meningitis in the adult (meningococcal or pneumococcal). 

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