Table 2.
Laboratory, EEG and radiological findings stratified by disease severity
| Laboratory findings | All patients n = 153 |
Severity | p value‡ | |||
|---|---|---|---|---|---|---|
| Mild n = 48 | Moderate n = 83 | Severe n = 22 | ||||
| Blood | ||||||
| Leukocytes (at admission) × 10 9/L, median (IQR), n = 152 | 10.1 (7.3–12.1) | 9.7 (6.9–11.7) | 10.1 (7.4–12.0) | 11.5 (7.4–13.0) | 0.420 | |
| CRP (highest value registered during stay) mg/L, median (IQR) | 19.0 (8.0–41.0) | 12.0 (5.0-21.5) | 18.0 (8.0–41.0) | 30.0 (26.0–66.0) | < 0.001*† | |
| Hyponatremia ξ, | n (%) | 97 (63.4) | 25 (52.1) | 56 (67.5) | 16 (72.7) | 0.131 |
| (Lowest value registered during stay) mmol/L, median (IQR), n = 97 | 133 (130–134) | 133 (130–134) | 134 (132–136) | 129 (128–132) | < 0.001*† | |
| CSF | ||||||
| Lumbar puncture, n (%) | 144 (94.1) | 42 (87.5) | 80 (96.4) | 22 (100.0) | 0.051 | |
| Pleocytosis (> 5 leukocytes, x 10 9/L), n (%) n = 143a | 132 (92.3) | 36 (85.7) | 75 (94.9) | 21 (95.5) | 0.164 | |
| Leukocytes x 10 9/L, median (IQR), n = 132b | 71 (35–130) | 66 (28–122) | 67 (36–131) | 96 (53–150) | 0.182 | |
| % monocytes, median (IQR) | 77 (48–91) | 78 (2–39) | 77 (54–91) | 69 (28.5–88.5) | 0.655 | |
| Glucose ratio, median (IQR), n = 126 | 0.6 (0.5–0.6) | 0.6 (0.5–0.6) | 0.6 (0.5–0.6) | 0.6 (0.5–0.7) | 0.340 | |
| Protein, g/L, median (IQR), n = 144 | 0.69 (0.54–0.93) | 0.59 (0.48–0.77) | 0.71 (0.57–0.92) | 0.83 (0.62–0.97) | 0.025* | |
| Albumin ratio, median (IQR), n = 97 | 12.3 (9.1–17.0) | 9.4 (8.0–13.0) | 12.6 (10.0-17.8) | 16.3 (14.0-21.6) | 0.005* | |
| EEG and radiological findings | ||||||
|
EEG suggesting encephalitis (performed n = 59), n % |
46/59 (78.0) | 0/6 (0) | 31/38 (81.6) | 15/15 (100) | < 0.001* | |
|
CT caput suggesting encephalitis (performed n = 110), n % |
3/110 (2.7) | 0/32 (0) | 2/58 (3.5) | 1/20 (5.0) | - | |
|
MRI cerebri suggesting encephalitis (performed n = 96), n % |
17/96 (17.7) | 0/18 (0) | 11/60 (18.3) | 6/18 (33.3) | 0.018* | |
The median blood neutrophil, lymphocyte, and platelet counts were within the normal range (not shown in Table 2), with the exception of the white blood cell count, which was slightly above the normal range. We identified 22 (18.2%) patients (8 with mild disease, 9 with moderate disease and 5 with severe disease) with increased transaminase levels. No significant differences in blood test results between the study groups were observed
IQR, interquartile range; TBE, tick-borne encephalitis; CSF, cerebrospinal fluid; S, serum; EEG, electroencephalography; CT, computerized tomography; MRI, magnetic resonance imaging
‡ Kruskal–Wallis test, Fisher’s exact test or Pearson’s chi-square test were used as appropriate
† Details significant for comparison test with Bonferroni adjustment: CRP, mild vs. severe (adj. p value < 0.001), moderate vs. severe (adj. p value = 0.012); hyponatremia, mild vs. moderate (adj. p value = 0.030), mild vs. severe (adj. p value = 0.033), moderate vs. severe (adj. p value < 0.001); Sp-protein, mild vs. severe (adj. p value = 0.013); Albumin ratio, milld vs. moderate (adj. p value = 0.044); mild vs. severe (adj. p value = 0.002)
ξ Hyponatremia: only values less than the normal range were recorded; not applicable
* p value < 0.05
a143/144 CSF samples were analyzed for leukocytes
bLeukocytes in CSF are shown for CSF samples with pleocytosis
A cA value < 10.2 was considered consistent with an intact blood‒brain barrier. Albumin ratio = CSF-albumin: Serum-albumin