There is a potentailly harmful myth that cerebrospinal fluid leaks should be treated with antibiotic prophylaxis [1]. This lacks an evidence
base and there are sound practical reasons why this practice will not be . This issue was addressed by a Working Group of the British
Society for Antimicrobial Chemotherapy [2]. The reasons put forward were:

1. Commonly used antibiotics such as cephalosporins penetrate the non
-inflamed meninges poorly

2. Antibiotics are unlikely to eradicate potential pathogens such as
the pneumococcus from the upper respiratory tract. Conversely treatment
may lead to colonisation with antibiotic resistant strains such as those
resistant to penicillin [3]. These may then replace the more easily
treatable sensitive strains in any future episodes of meningitis.

Published reviews have failed to show that prophylactic treatment is
effective and as such should be discouraged.

Resistance of microbes to antimicrobial agents is rising throughout
the world. Indiscriminate use of these agents is often to blame and is
associated with bacterial superinfections by organisims such as MRSA,
antibiotic associated diarrhoea and drug specific side effects. Reduction
in antibiotic use may not reverse this trend in rising resistance but will
attenuate it as well as protecting patients against drug side effects and
health care systems against the financial costs. Prudent and appropriate
prescribing of antibiotics must be the ultimate goal.

[1]. Santarius T, Antoun NM, Kirollos RW. Minerva. Brit Med J 2002;
325: 554.

[2]. Antimicrobial prophylaxis in neurosurgery and after head injury.
Lancet 1994; 344: 1547-1551.

[3]. Heikkinen T, Saeed KA, McCormick DP, Baldwin C, Reisner BS,
Chonmaitree T. A single intramuscular dose of ceftriaxone changes
nasopharyngeal bacterial flora in children with acute otitis media. Acta
Paediatr 2000; 89: 1316-1321.