Volume 28, Number 2—February 2022
CME ACTIVITY - Synopsis
Clinical and Laboratory Characteristics and Outcome of Illness Caused by Tick-Borne Encephalitis Virus without Central Nervous System Involvement
Petra Bogovič
, Andrej Kastrin, Stanka Lotrič-Furlan, Katarina Ogrinc, Tatjana Avšič Županc, Miša Korva, Nataša Knap, and Franc Strle
, Andrej Kastrin, Stanka Lotrič-Furlan, Katarina Ogrinc, Tatjana Avšič Županc, Miša Korva, Nataša Knap, and Franc Strle
Table 3
Basic demographic, clinical, and laboratory characteristics of febrile illness caused by tick-borne encephalitis virus infection with or without subsequent central nervous system involvement*
| Characteristic | Febrile illness followed by CNS involvement, n = 52 |
Febrile illness with possible later CNS involvement, n = 4 |
Febrile illness without later CNS involvement, n = 6 |
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|---|---|---|---|---|---|---|
| Sex | ||||||
| F | 26 (50.0, 35.8–64.2) | 2 (50.0, 6.8–93.2) | 3 (50.0, 11.8–88.2) | |||
| M |
26 (50.0, 35.8–64.2) |
2 (50.0, 6.8–93.2) |
3 (50.0, 11.8–88.2) |
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| Median age, y (IQR) |
50 (40.75–62) |
52 (51.75–55) |
45.5 (34.5–55) |
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| Underlying illnesses |
22 (42.3, 28.7–56.8) |
0 (0, 0–60.2) |
3 (50.0, 11.8–88.2) |
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| History of tick bite† |
45/51 (88.2, 76.1–95.6) |
3/4 (75.0, 19.4–99.4) |
5/6 (83.3, 35.9–99.6) |
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| Median incubation period, d (IQR)‡ |
6 (4.5–9.5)§ |
9 (9–9)¶ |
6.5 (3–11)# |
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| Median duration of illness before first evaluation, d (IQR) |
5 (3.75–7) |
5.5 (5–6.25) |
5 (4.25–6.5) |
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| Clinical manifestation | ||||||
| Body temperature >37.5°C | 51/52 (98.1, 89.7–100) | 3/4 (75.0, 19.4–99.4) | 6 (100, 54.1–100) | |||
| Median body temperature, °C (IQR)** | 38.5 (38–39) | 38.3 (38.05–38.45) | 39 (38.625–39) | |||
| Chills | 10 (19.2, 9.6–32.5) | 1 (25.0, 0.6–80.7) | 1 (16.7, 0.4–64.1) | |||
| Headache | 47 (90.4, 79.0–96.8) | 2 (50.0, 6.8–93.2) | 6 (100, 54.1–100) | |||
| Myalgias | 27 (51.9, 37.6–66.0) | 3 (75.0, 19.4–99.4) | 3 (50.0, 11.8–88.2) | |||
| Arthralgias | 22 (42.3, 28.7–56.8) | 3 (75.0, 19.4–99.4) | 2 (33.3, 4.3–77.7) | |||
| Gastrointestinal symptoms | 24 (46.2, 32.2–60.5) | 2 (50.0, 6.8–93.2) | 3 (50.0, 11.8–88.2) | |||
| Abdominal pain | 1 (1.9, 0.1–10.3) | 1 (25.0, 0.6–80.7) | 0 (0, 0–45.9) | |||
| Nausea, vomiting | 22 (42.3, 28.7–56.8) | 2 (25.0, 0.6–80.7) | 2 (33.3, 4.3–77.7) | |||
| Diarrhea | 6 (11.5, 4.4–23.4) | 2 (50.0, 6.8–93.2) | 1 (16.7, 0.4–64.1) | |||
| Malaise or fatigue | 52 (100, 93.2–100) | 4 (100, 39.8–100) | 5 (83.3, 35.9–99.6) | |||
| Respiratory symptoms | 7 (13.4, 5.6–25.8) | 0 (0, 0–60.2) | 1 (16.7, 0.4–64.1) | |||
| Sore throat | 7 (13.4, 5.6–25.8) | 0 (0, 0–60.2) | 1 (16.7, 0.4–64.1) | |||
| Cough |
1 (1.9, 0.1–10.3) |
0 (0, 0–60.2) |
0 (0, 0–45.9) |
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| Median duration of illness, d (IQR) |
7 (6–8)†† |
8 (7–9)‡‡ |
9 (7.5–9.75) |
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| Hospitalization | ||||||
| No. hospitalized patients | 20 (38.5, 25.3–53.0) | 2 (50.0, 6.8–93.2) | 3 (50.0, 11.8–88.2) | |||
| Median duration, d (IQR) |
4 (1–6)§§ |
4.5 (3.75–5.25) |
4 (2.5–5) |
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| Laboratory findings | ||||||
| Median blood leukocyte count, × 109/L (IQR) | 2.2 (1.8–2.85)¶¶ | 1.7 (1.675–1.95) | 2.95 (2.5–4.15) | |||
| Blood leukocyte count <4 × 109/L | 50 (100, 92.9–100) | 4 (100, 39.8–100) | 4 (66.7, 22.3–95.7) | |||
| Blood leukocyte count >10 × 109/L | 0 (0, 0–7.1) | 0 (0, 0–60.2) | 0 (0, 0–45.9) | |||
| Median blood platelet count, × 109/L (IQR) | 125.5 (108.25–152.75)¶¶ | 110 (86–134.25) | 139 (118.5–162.5) | |||
| Blood platelet count <140 × 109/L | 34 (68.0, 53.3–80.5) | 3 (75.0, 19.4–99.4) | 3 (50.0, 11.8–88.2) | |||
| Serum C-reactive protein elevated,
>5 mg/L |
3/50 (6.0, 1.3–16.6)## |
0 (0, 0–60.2) |
1 (16.7, 0.4–64.1)*** |
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| Liver tests, µkat/L (IQR) | ||||||
| Median aspartate aminotransferase | 0.605 (0.4575–0.84)††† | 1.05 (0.59–3.55) | 0.62 (0.5075–0.845) | |||
| Elevated >0.58 | 26 (54.2, 39.2–68.6) | 3 (75.0, 19.4–99.4) | 4 (66.7, 22.3–95.7) | |||
| Median alanine aminotransferase | 0.535 (0.4–0.82)††† | 1.285 (0.48–3.5225) | 0.56 (0.3475–0.78) | |||
| Elevated >0.77 µkat/L |
13 (27.1, 15.3–41.9) |
2 (50.0, 6.8–93.2) |
2 (33.3, 4.3–77.7) |
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| No. patients with >1 abnormal liver test result | 29/48 (60.4, 45.3–74.2) |
3 (75.0, 19.4–99.4) |
4 (66.7, 22.3–95.7) |
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*Values are no. (%, 95% CI) except as indicated. CNS, central nervous system; IQR, interquartile range. †Tick bite within 4 weeks before onset of illness. ‡Time (d) from tick bite to onset of illness calculated only in patients with 1 bite. §Data available for 27 patients. ¶Data available for 1 patient. #Data available for 4 patients. **The highest temperature in the course of the illness. ††Data available for 45 patients. ‡‡Data available for 2 patients. §§Data available for 17 patients. ¶¶Data available for 50 patients. ##Median 6, range 6–9. ***Value 45. †††Data available for 48 patients.
Page created: December 02, 2021
Page updated: January 21, 2022
Page reviewed: January 21, 2022
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