The Seeplex Meningitis ACE detection kit detected causative pathogens for 37 cases (47.4%) that tested negative in the conventional studies. Two patients had single bacterial infection with GBS and LM, and CSF analysis revealed bacterial and undetermined features, respectively. Single viral infections were evident in 16 patients with HEV, 9 with VZV, 3 with HSV-1, and 1 each with HSV-2 and EBV. All the cases with positive results for viruses showed viral or undetermined features in CSF analysis. Five patients showed simultaneous infection with 2 bacterial or viral pathogens: 2 tested positive for both SP and HEV and 1 each tested positive for SP and HSV-1, SP and VZV, and EBV and HSV-1. One of the cases positive for both SP and HEV had CSF findings compatible with bacterial meningitis, while the others had features consistent of viral meningitis, with lymphocyte dominance and high glucose level. Sequencing of amplicons showed no evidence of false-positive cross-reactivity; the rates of BLAST match were 98-100%. CSF samples obtained from the remaining 34 patients did not test positive with the Seeplex kit. Sequential work-up with conventional studies showed that 1 patient each was infected with EBV, VZV, SP, HEV, and HSV-1 and had consistent CSF findings. The pathogenic agents in the other 29 patients could not be identified, although CSF analysis indicated that 6 had bacterial infection, 13 had viral infection, and the remaining 10 had indeterminate findings. None of the control cases showed false-positive results.