Adult Enterobacter meningitis : A high incidence of coinfection with other pathogens and frequent association with neurosurgical procedures

The clinical characteristics of Enterobacter infection in adult bacterial meningitis were defined. The clinical manifestations and therapeutic outcomes of ten adult patients with Enterobacter infections in acute bacterial meningitis were analyzed. Enterobacter infection was found in 4.5% (10/223) of our adult patients with culture-proven bacterial meningitis. The ten patients comprised seven men and three women aged between 16-69 years (mean 47 years). Coinfections with other pathogens were found in 50% of the cases, the most common pathogen being Klebsiella pneumoniae. Nine of the ten patients had a history of neurosurgery, and seven patients contracted the infection nosocomially. Multiple antibiotic-resistant strains, including resistance to third-generation cephalosporins, were found in three patients with polymicrobial infections. These three patients received iv imipenem/cilastin therapy. The therapeutic results showed that two of the ten patients died; five of the eight surviving patients had neurological sequelae. The predominant coinfection with Enterobacteriaceae in adult Enterobacter meningitis may reflect the fact that most of the cases of polymicrobial Enterobacter infections have a potential gastrointestinal source. A postneurosurgical state was the most important predisposing factor for the development of Enterobacter infection in adult bacterial meningitis in our patients. The strains of the Enterobacter species in adult polymicrobial Enterobacter meningitis were commonly resistant to multiple antibiotics, including third-generation cephalosporins. In light of the high incidence of multiple antibiotic-resistant Enterobacter strains in adult polymicrobial Enterobacter meningitis, the choice of initial empiric antibiotics may include carbapenem (imipenem/cilastin or meropenem). Although the mortality rate was not high in this group of patients, most survivors suffered neurological sequelae.