Clinical Characteristics of Adult Escherichia coli Meningitis

SUMMARY: The clinical characteristics and therapeutic outcomes of adult meningitis due to Escherichia coli alone have not been examined adequately. In this study, we analyzed the clinical and laboratory data of 15 adult patients with monomicrobial E. coli meningitis. The 15 patients, collected over a period of 18 years (January 1986 - December 2003), included 7 men and 8 women, aged 45 - 77 years. They accounted for 5% (15/306) of our cases of adult bacterial meningitis with single pathogen infection. This study also revealed that a postneurosurgical state is the most important factor predisposing adult patients to develop E. coli meningitis. In this study, all of the tested E. coli strains showed susceptibility to imipenem and/or meropenem, however, E. coli strains that are not susceptible to third-generation cephalosporin have emerged since 2001. As to the therapeutic results of these 15 cases, all 4 patients without appropriate antibiotic treatment died and the other 11 patients with appropriate antibiotic treatment showed a mortality rate of 27%. The emergence of third-generation cephalosporin non-susceptible E. coli strains in adult bacterial meningitis, as shown in this study, has created a therapeutic challenge in choosing initial empirical antibiotics for treating adult patients with post-neurosurgical meningitis. Our results emphasize that the timely use of appropriate antibiotics is essential for the management of this potentially fatal central nervous system infection. However, it should be noted that the number of cases examined in this study is too small to reach a therapeutic conclusion regarding adult E. coli meningitis, and further largescale studies will be needed for this purpose.