Table 2. Patient characteristics and comparisons between patients with or without a confirmed viral aetiology.
| Patient characteristics | Whole group (n = 291) | Unknown/possible causes (n = 192)$ | Confirmed/probable viral aetiology (n = 93) | Diag. vs. undiag. P value (OR; 95%CI) |
| Demographics | ||||
| Male | 190 (65) | 125 (65) | 61 (66) | 1 (1.02; 0.59–1.78) |
| Age | 25 (19–34) | 26 (20–35) | 22 (17–32) | 0.005 |
| Referral from other hospital | 235 (89) | 151 (88) | 78 (92) | 0.62 (1.21; 0.55–2.67) |
| Hospitalization (days) | 10 (7–18) | 10 (7–20) | 9 (6–15) | 0.005 |
| Symptom | ||||
| Day of illness | 6 (3–8) | 6 (4–9) | 5 (3–7) | 0.13 |
| History of fever | 263 (91) | 168 (88) | 90 (99) | 0.002 (12.85; 1.71–96.60) |
| Vomiting | 143 (53) | 86 (48) | 54 (62) | 0.028 (1.78; 1.06–3.01) |
| Headache | 234 (82) | 148 (79) | 82 (90) | 0.023 (2.40: 1.10–5.20) |
| Convulsion | 77 (29) | 57 (32) | 19 (24) | 0.19 (0.64; 0.33–1.21) |
| Sign | ||||
| Fever at admission | 181 (62) | 118 (62) | 61 (66) | 0.51 (1.19; 0.69–2.08) |
| Neck stiffness | 162 (65) | 103 (64) | 56 (68) | 0.48 (1.23; 0.68–2.27) |
| Cranial nerve palsies | 17 (6) | 11 (6) | 6 (7) | 0.79 (1.14; 0.33–3.52) |
| Skin rash | 15 (5) | 8 (4) | 6 (7) | 0.39 (1.58; 0.44–5.39) |
| GCS≤9 | 83 (29) | 62 (32) | 21 (23) | 0.09 (0.61; 0.32–1.11) |
| GCS = 15 and No focal Neurological signs | 75 (28) | 51 (27) | 24(28) | 0.89(0.59; 1.04–1.85) |
| Laboratory | ||||
| CSF WC (cells/mm3) | 93 (24–247) | 58 (12–176) | 180 (82–371) | <0.001 |
| CSF protein (g/l) | 0.8 (0.48–1.12) | 0.75(0.4–1.1) | 0.87(0.57–1.19) | 0.31 |
| CSF lactate (mmol/l) | 2.3 (1.8–2.89) | 2.3(1.8–2.9) | 2.4(1.8–2.7) | 0.97 |
| CSF/blood glucose | 0.6 (0.52–0.68) | 0.62 (0.52–0.71) | 0.59(0.53–0.66) | 0.20 |
| Antiviral treatment | 71 (24) | 46(24) | 25(27) | 0.66(1.16; 0.63–2.12) |
| Acyclovir | 41* | 24(12.5) | 18(19) | |
| Valacyclovir | 30 | 22(11.5) | 7(8) | |
| Outcome at discharge | ||||
| Death | 28 (10) | 15 (8) | 13 (14) | 0.48 |
| Severe sequelae | 49 (17) | 33 (17) | 15 (16) | |
| Moderate sequelae | 17 (6) | 11 (6) | 6 (7) | |
| Mild sequelae | 12 (4) | 9 (5) | 2 (2) | |
| Full recovery# | 183 (63) | 122 (64) | 57 (61) |
Note: Data are Number (%) of patients, denominators may vary slightly; continuous variables were reported as median, interquartile range; Diag: diagnosed, undiag: undiagnosed;
the 6 patients with bacterial DNA detected in CSF alone or together with EBV DNA were not included in this patient group. As comparison found not statistical difference in clinical outcomes and patient characteristics between patients with possible viral diagnoses and those with no diagnoses (data not shown) except for CSF WCC: median 170 cells/mm3 (IQR 70–305) vs. 54 (IQR 11–160), respectively (P = 0.03), clinical data of these two groups were combined and compared against patient group of definitive or probable viral diagnosis;
*of whom one was treated with intravenous acyclovir on admission and one had oral acyclovir 5 days after admission before being treated with intravenous acyclovir.
full recovery was based on clinical evaluation at hospital discharge and did not include cognitive assessment, learning, etc.