CALCA and bacterial meningitis: Table 3 shows the efficacy of PCT (with diagnostic cut-off point > 0.5 ng/ml) compared to TLC (> 11,000/mm3), CSF TLC (> 10 cells/mm3), CSF neutrophil count (> 60%), CSF glucose (< 60% of blood glucose) and CSF protein (> 45 mg/dl) for diagnosis of bacterial meningitis.