Time to positive culture can differentiate post-neurosurgical coagulase-negative Staphylococci other than S epidermidis meningitis from contamination: A case-control observational study.

OBJECTIVE To explore the characteristics of coagulase-negative Staphylococci other than Staphylococci epidermidis (Nse-CoNS) meningitis and to apply cerebrospinal fluid (CSF) times to positivity culture (TTPC) for the precise differentiation of meningitis from contamination. METHODS We conducted a case-control study to accomplish the following: First, we retrospectively reviewed records of post-neurosurgical patients' CSF that yielded Nse-CoNS from January to October 2019 at the Beijing Tiantan Hospital; 17 clinical and 12 laboratory characteristics were reviewed. Second, we investigated the TTPC of the Nse-CoNS, the cutoffs, and corresponding parameters to differentiate Nse-CoNS meningitis from contamination. RESULTS In this study, a total of 146 patients with Nse-CoNS CSF culture positive were enrolled. The average TTPC in the Nse-CoNS meningitis group was significantly shorter than in the contamination group (20.2 ± 5.0 hours and 30.2 ± 12.6 hours, respectively, P < .05). The area under curve (AUC) of the model was 0.802. A TTPC of 20.0 hours had 94.3% sensitivity and a negative value of 90.2% for predicting Nse-CoNS meningitis. CONCLUSIONS Nse-CoNS meningitis often causes confusion in clinical diagnosis. In this study, we evaluated the clinical predictive factors of Nse-CoNS meningitis and confirmed that the median TTPC in the Nse-CoNS meningitis group was significantly shorter than in the contamination group. A TTPC shorter than 20.0 hours was associated with Nse-CoNS meningitis, while a TTPC longer than 20.0 hours was associated with Nse-CoNS contamination. This information will be helpful for the rapid diagnosis of Nse-CoNS meningitis.