Table 3.
Comparison of laboratory results on presentation
| All | IBI | Probable AEFI | Possible AEFI | UTI | P value (IBI vs probable AEFI) | |
| Number of participants | 188 (100) | 40 (21) | 97 (52) | 24 (13) | 27 (14) | – |
| Laboratory results—routine blood tests | ||||||
| WCC on presentation (109/L) | 16.1 (10.4–19.7 (101) | 14.2 (8.6–19.0 (3) | 16.7 (13.6–19.4) (71) | 16.7 (12.3–20.7) (12) | 18.7 (10.5–20.6) (15) | 0.113 |
| Percentage of WCC on presentation above laboratory reference range for age (15×109/L) (%) | 54 | 46 | 62 | 58 | 58 | – |
| NC on presentation (109//L) | 7.4 (5.3–11.6) (101) | 7.0 (3.1–10.8) (3) | 8.6 (6.0–11.9) (71) | 5.7 (3.8–8.0) (12) | 8.8 (7.2–11.8) (15) | 0.697 |
| Percentage of NC on presentation above laboratory reference range for age (8×109//L) | 45% | 43% | 50% | 25% | 58% | – |
| LC on presentation (109//L) | 5.3 (3.0–7.2) (101) | 4.7 (2.8–6.0) (3) | 5.1 (3.2–7.3) (71) | 7.7 (5.7–9.8) (12) | 4.9 (2.7–6.4) (15) | 0.231 |
| CRP on presentation (mg/L) | 26 (9–74) (104) | 46 (8–146) (6) | 16 (10–28) (70) | 12 (7–60) (12) | 65 (44–88) (16) | 0.012 |
| Percentage (%) of CRP on presentation above laboratory reference range for age (5 mg/L) | 87 | 82 | 89 | 83 | 100 | – |
| Highest WCC in first 72 hours (109//L) | 16.3 (10.6–19.7) (98) | 15.0 (9.1–19.1) (2) | 17.4 (13.8–19.2) (70) | 16.2 (11.1–20.7) (11) | 18.7 (10.5–20.6) (15) | 0.406 |
| Highest NC in first 72 hours (109//L) | 7.4 (5.4–11.7) (98) | 7.2 (3.4–11.5) (2) | 9.2 (6.0–11.8) (70) | 5.6 (3.6–7.5) (11) | 8.8 (7.2–11.8) (15) | 0.732 |
| Highest LC in first 72 hours (109//L) | 5.8 (3.5–7.6) (98) | 5.5 (3.4–7.2) (2) | 5.7 (3.3–7.4) (70) | 7.9 (5.8–9.7) (11) | 5.5 (2.7–6.4) (15) | 0.609 |
| Highest CRP in first 72 hours (mg/L) | 31 (11–77) (102) | 58 (11–151) (5) | 19 (10–30) (70) | 16 (8–56) (11) | 65 (44–88) (16) | 0.007 |
| Blood cultures | ||||||
| Pathological growth | 37 (20) | 37 (92) | 0 (0) | 0 (0) | 0 (0) | – |
| Negative | 51 (27) | 3 (8) | 26 (27) | 12 (50) | 10 (37) | |
| Contaminant | 4 (2) | 0 (0) | 3 (3) | 0 (0) | 1 (4) | |
| Not determined/not performed | 96 (51) | 0 (0) | 68 (70) | 12 (50) | 16 (59) | |
| Urine dipstick | ||||||
| Leucocyte positive | 36 (51) | 10 (71) | 3 (12) | 3 (38) | 20 (91) | 0.004 |
| Nitrite positive | 15 (21) | 4 (29) | 0 (0) | 1 (12) | 10 (45) | 0.010* |
| Not determined/not performed | 118 (63) | 26 (65) | 71 (73) | 16 (67) | 5 (19) | 0.154 |
| Laboratory results—lumbar puncture testing | ||||||
| Culture | ||||||
| Positive | 6 (11) | 5 (21) | 0 (0) | 0 (0) | 1 (12) | – |
| No growth | 48 (89) | 19 (79) | 13 (100) | 9 (100) | 7 (88) | |
| No LP culture | 134 (71) | 16 (40) | 84 (87) | 15 (62) | 19 (70) | |
| Biochemistry | ||||||
| Protein (mg/L) | 340 (248–535) (136) | 305 (240–514) (17) | 334 (276–529) (84) | 579 (352–01) (15) | 282 (234–364) (20) | 0.442 |
| Glucose (mmol/L) | 3.2 (2.9–3.6) (135) | 3.4 (2.6–3.8) (16) | 3.0 (2.9–3.4) (84) | 3.1 (2.9–3.2) (15) | 3.4 (3.2–3.8) (20) | 0.978 |
| Lactate (mmol/L) | 1.3 (1.1–1.5) (152) | 1.6 (1.0–2.3) (30) | 1.3 (1.2–1.5) (86) | 1.2 (1.1–1.4) (16) | 1.3 (1.1–1.4) (20) | 0.152 |
| Cell count | ||||||
| WCC (106/L) | 0 (0–2) (137) | 0 (0–2) (19) | 0 (0–2) (84) | 4 (2–6) (15) | 0 (0–0) (19) | 0.562 |
| PMNs (106/L) | 0 (0–0) (137) | 0 (0–0) (19) | 0 (0–0) (84) | 2 (0–2) (15) | 0 (0–0) (19) | 0.696 |
| Lymphocytes (106/L) | 0 (0–2) (137) | 0 (0–2) (19) | 0 (0–2) (84) | 2 (2–6) (15) | 0 (0–0) (19) | 0.464 |
Categorical variables are reported as number (percentage of total, %) (number of missing results). Continuous variables are reported as median (IQR) (number of missing results). P values are reported for comparison between IBI and probable AEFI groups and are adjusted for age and sex. P values <0.05 are highlighted in bold.
*Indicates comparison using Fisher’s exact test, unadjusted for age or sex.
AEFI, adverse event following immunisation; CRP, C-reactive protein; IBI, invasive bacterial infection; LC, lymphocyte count; NC, neutrophil count; PMN, polymorphonuclear leucocyte; UTI, urinary tract infection; WCC, white cell count.