Protean infectious types and frequent association with neurosurgical procedures in adult Serratia marcescens CNS infections: report of two cases and review of the literature.

Serratia marcescens is a rare pathogen of adult central nervous system (CNS) infection. We report on the clinical features and therapeutic outcomes of two adult patients with such infections. The clinical characteristics of 13 other reported adult cases are also included for analysis. The 15 cases were nine males and six females, aged 19-83 years, in whom, underlying post-neurosurgical states and ear operation were noted in 93% (14/15). Fever and conscious disturbance were the most common clinical manifestations of these 15 cases, followed by hydrocephalus, seizures, and wound infections. The manifestation types were protean, including meningitis and focal suppurations such as brain abscess, cranial and spinal epidural abscess, cranial subdural abscess, and infected lumbar pseudomeningocele. One case of S. marcescens CNS infection was diagnosed postmortem; the other 14 were diagnosed by the positive culture from CSF or pus. Antibiotic therapy with or without neurosurgical intervention was the management strategy in 14/15 cases. The therapeutic results showed a high mortality rate.