Demographics and risk factors for S. aureus invasive blood infections bacteremia
| Variable | All infants receiving sepsis evaluations (n= 3279) | Infants without bacteremia (n=3102) | Infants with non-S. aureus bacteremia (n = 118) | Infants with S. aureus bacteremia* (n=59) | P value (SA vs. non-SA bacteremia vs. non-infected) |
|---|---|---|---|---|---|
| Birthweight, grams (median; 25-75th) | 2050; 865-2920 | 2090; 895-2933 | 1400; 709-2650 | 1010; 700-2700 | 0.006 |
| Preterm (<37 weeks) (n,%) < 28 28-34 34-37 | 890, 27% 653, 20% 668, 20% | 821, 26% 612, 20% 638, 21% | 43, 37% 26, 22% 25, 21% | 26, 44% 15, 25% 5, 8% | 0.001 |
| Postnatal age at diagnosis, days (median; 25-75th) | 41; 10-99 | 41; 10-99 | 37; 16-101 | 39; 19-89 | 0.35 |
| Gender (n,%) Male Female | 1824, 56% 1452, 44% | 1726, 56% 1373, 44% | 66, 56% 52, 44% | 32, 54% 27, 46% | 0.97 |
| Race (n,%)~ White Black Asian Multiracial Other/unknown | 1520,46% 739, 23% 134, 4% 141, 4% 745, 23% | 1450, 47% 679, 22% 127, 4% 134, 4% 712, 23% | 43, 36% 39, 33% 7, 6% 5, 4% 24, 20% | 27, 46% 21, 36% 0, 0% 2, 3% 9, 15% | 0.014 |
| Hispanic ethnicity (n,%) | 537, 17% | 512, 17% | 19, 16% | 6, 10% | 0.43 |
| Temperature instability (n,%)** Fever Hypothermia | 1083, 33% 762, 23% 356, 11% | 1014, 33% 704, 23% 340, 11% | 48, 41% 39, 33% 13, 11% | 21, 36% 19, 32% 3, 5% | 0.18 0.008 0.39 |
| Receiving ventilatory support (n,%)** Conventional HFOV@ | 2075, 63% 1567, 48% 508, 15% | 1961, 63% 1496, 48% 465, 15% | 71, 61% 49, 42% 22, 19% | 43, 72% 22, 37% 21, 36% | 0.24 0.1 <0.001 |
| Hypotension (n,%)** | 695, 21% | 655, 21% | 24, 20% | 16, 27% | 0.52 |
| ECMO (n,%)** | 129, 4% | 120, 4% | 4, 3% | 5, 8% | 0.19 |
| Steroid use (n,%)** | 605, 18% | 562, 18% | 24, 20% | 19, 32% | 0.02 |
| Central line present (n,%)** | 1834, 56% | 1721, 56% | 70, 59% | 43, 73% | 0.02 |
| Length of stay, days (median, 25-75th)# Survivors | 103; 41-204 105; 43-209 | 102; 41-203 105; 42-209 | 121; 46-198 125; 54-214 | 125; 37-253 142; 109-285 | 0.60 0.04 |
| Any death (n,%)# Death<30 days | 593/3028, 20% 260/3028, 9% | 549/2873, 19% 239/2873, 8% | 27/100, 27% 11/100, 11% | 17/55, 31% 10/55, 18% | 0.02 0.02 |
*S. aureus was present in both blood and urine in one episode, and both blood and respiratory cultures in 17 episodes. **Variables measured as ‘yes’ when present on day of sepsis evaluation. ~Race comparison done excluding ‘other/unknown’ category. #251 subjects still in hospital; excluded from length of stay and mortality calculations. @Patients transitioned between conventional ventilator and HFOV on same day were classified in the HFOV group.