To investigate the incidence, etiology and risk factors in patients with chronic meningitis who underwent cerebrospinal fluid drainage.

Clinical data of patients diagnosed with tubercular meningitis and fungal meningitis in Huashan Hospital, Fudan University from June 2011 to October 2016 were collected. The continuous data were compared by Mann-Whitney test. The categorical variables were analyzed by Fisher’s exact test.

Total of 29 patients with cerebrospinal fluid drainage (including external ventricular drainage and lumbar drainage) were enrolled, among whom, 6 patients underwent more than once drainage, thus a total of 35 cases were enrolled. Nine cases (25.7%) with secondary infection were identified. All the 9 CSF samples were collected for bacterial culture, 8 were positive with 3 of Staphylococcus epidermidis, 3 of Klebsiella pneumoniae, 2 of Acinetobacter baumannii, one of methicillin-resistant Staphylococcus aureus (MRSA) (Klebsiella pneumoniae and Acinetobacter baumannii were cultured in one patient successively). In the group of external ventricular drainage, patients who developed secondary infection were drained longer than those without secondary infection. The median time of patients in the two groups were 77 days and 24 days, respectively, with no significant difference. Further analysis showed that it was more likely to develop secondary infection for patients underwent external ventricular drainage whose Ommaya reservoirs were punctured more times compared with those without secondary infection, with significant difference (U = 12.0, P = 0.0059).

Secondary infection remained a common complication of cerebrospinal fluid drainage, and were comparatively induced by Gram positive cocci and Gram negative bacilli. More frequent puncture of Ommaya reservoir could increase the incidence of secondary infection.