Univariable associations between clinical variables and risk of serious bacterial infection (SBI) in children presenting to the emergency department
| Clinical variable | N* | SBI, n (%) | OR | 95% CI | p Value | |
|---|---|---|---|---|---|---|
| Age group | Infants (1–11 months) | 701 | 26 (3.7) | 1.35 | 0.31 to 5.81 | 0.784 |
| Preschool (12–59 months) | 855 | 31 (3.6) | 1.32 | 0.31 to 5.62 | ||
| School age (5–11 years) | 323 | 15 (4.6) | 1.70 | 0.38 to 7.65 | ||
| Adolescents (12–15 years) | 72 | 2 (2.8) | 1.00 | – | ||
| Sex | Male | 1081 | 39 (3.6) | 1.00 | – | 0.562 |
| Female | 850 | 35 (4.1) | 1.15 | 0.72 to 1.83 | ||
| Risk factor for infection† | No | 1898 | 66 (3.5) | 1.00 | – | <0.0001 |
| Yes | 53 | 8 (15.1) | 4.93 | 2.23 to 10.9 | ||
| Developmental delay | No | 1923 | 70 (3.6) | 1.00 | – | 0.003 |
| Yes | 28 | 4 (14.3) | 4.41 | 1.49 to 13.1 | ||
| Consciousness level (AVPU score) | Alert | 1913 | 70 (3.7) | 1.00 | – | 0.027 |
| Responds to voice | 18 | 0 (0.0) | 0.00 | – | ||
| Responds to pain | 5 | 2 (40.0) | 17.6 | 2.86 to 107.7 | ||
| Unresponsive | 1 | 0 (0.0) | 0.00 | – | ||
| State variation | Awake | 1909 | 68 (3.6) | 1.00 | – | <0.0001 |
| Eyes close briefly | 31 | 6 (19.4) | 6.50 | 2.57 to 16.4 | ||
| Falls asleep | 1 | 0 (0.0) | 0.00 | – | ||
| Temperature‡ | 35.0–36.4°C | 426 | 9 (2.1) | 0.82 | 0.37 to 1.82 | <0.0001 |
| 36.5–37.5°C | 780 | 20 (2.6) | 1.00 | – | ||
| 37.5–38.4°C | 205 | 17 (4.4) | 1.86 | 1.01 to 3.43 | ||
| ≥38.5°C | 305 | 28 (9.2) | 4.10 | 2.39 to 7.05 | ||
| Tachycardia | Not tachycardic | 974 | 22 (2.3) | 1.00 | – | 0.0001 |
| Tachycardic | 651 | 39 (6.0) | 2.76 | 1.61 to 4.71 | ||
| Capillary refill time | <2 s | 1755 | 65 (3.7) | 1.00 | – | <0.0001 |
| ≥2 s | 40 | 7 (17.5) | 5.52 | 2.34 to 13.0 | ||
| Hydration status | Well hydrated | 1834 | 58 (3.2) | 1.00 | – | <0.0001 |
| Dry mucous membranes | 102 | 12 (11.8) | 4.08 | 2.11 to 7.90 | ||
| Reduced skin turgor | 9 | 4 (44.4) | 24.5 | 6.30 to 95.3 | ||
| Hypotension§ | Not hypotensive | 1947 | 74 (3.8) | 1.00 | – | 0.691 |
| Hypotensive | 4 | 0 (0.0) | 0.00 | – | ||
| Tachypnoea | Not tachypnoeic | 656 | 19 (2.9) | 1.00 | – | 0.028 |
| Tachypnoeic | 932 | 48 (5.2) | 1.82 | 1.06 to 3.13 | ||
| Hypoxia | Not hypoxic | 1620 | 49 (3.0) | 1.00 | – | <0.0001 |
| Mild hypoxia | 265 | 16 (6.0) | 2.06 | 1.15 to 3.68 | ||
| Severe hypoxia | 66 | 9 (13.6) | 5.06 | 2.36 to 10.9 | ||
| Purpuric rash | None | 1666 | 66 (4.0) | 1.00 | – | 0.641 |
| Purpuric rash | 16 | 1 (6.3) | 1.62 | 0.21 to 12.4 | ||
| Petechial rash | None | 1666 | 66 (4.0) | 1.00 | – | 0.793 |
| Petechial rash | 42 | 2 (4.8) | 1.21 | 0.29 to 5.13 | ||
| Macular rash | None | 1757 | 70 (4.0) | 1.00 | – | 0.184 |
| Macular rash | 194 | 4 (2.1) | 0.51 | 0.18 to 1.41 |
* N indicates the total number children in a particular category. Note that the sum of N across all categories of a particular variable is equal to the total number of children for which data were available for that variable. For most variables this is less than the total number of children (1032) included in the analysis due to missing data for that particular variable.
† Identified risk factors for bacterial infection in this analysis included neutropaenia, sickle cell disease, primary ciliary dyskinesia, Down's syndrome, glycogen storage disease 1b, Hunter's syndrome, Hurler's syndrome, cryptogenic cirrhosis, biliary atresia, vesico-ureteric reflux, hydronephrosis, congenital pneumonia and a documented history of recurrent bacterial infections.
‡ Temperature categories 35.0–36.4°C and 36.5–37.5°C were combined in the multivariate analysis to allow temperature to be modelled as a linear variable. No children had a temperature <35.0°C in this study.
§ Blood pressure recordings were only available for 94 children; the remaining children were classified as not hypotensive for the purposes of the analysis.