Table 1.
Study participants characteristics at admission
| All young infant admissions (N=12 271)* | Young infant admissions KHDSS residents (N=4421) | Young infant admissions non-KHDSS residents (N=7850) | P value | |
| Demographics | ||||
| Age in days | ||||
| 0–2 | 7856 (64) | 2731 (62) | 5125 (65) | <0.001 |
| 3–7 | 1384 (11) | 468 (11) | 916 (12) | |
| 8–28 | 1506 (12) | 587 (13) | 919 (12) | |
| >28 | 1525 (12) | 635 (14) | 890 (11) | |
| Sex (female) | 5245 (43) | 1900 (43) | 3345 (43) | 0.70 |
| Reported born premature | 2970 (24) | 1019 (23) | 1951 (25) | 0.005 |
| Reported low birth weight | 1782 (15) | 581 (13) | 1201 (15) | <0.001 |
| Born at KCH | ||||
| Yes | 6757 (55) | 2743 (62) | 4014 (51) | <0.001 |
| No | 5514 (45) | 1678 (38) | 3836 (49) | |
| Anthropometry | ||||
| Weight (kg) | ||||
| <1.5 | 1767 (14) | 566 (13) | 1201 (15) | <0.001 |
| 1.5 to <2.5 | 3211 (26) | 1128 (26) | 2083 (27) | |
| ≥2.5 | 7193 (59) | 2684 (61) | 4509 (57) | |
| Missing | 100 (0.8) | 43 (1.0) | 57 (0.7) | |
| MUAC (cm) | ||||
| <9 | 3933 (32) | 1342 (30) | 2591 (33) | <0.001 |
| 9–10 | 2492 (20) | 862 (20) | 1630 (21) | |
| 10–11 | 2926 (24) | 1035 (23) | 1891 (24) | |
| ≥11 | 2622 (21) | 1056 (24) | 1566 (20) | |
| Missing | 298 (2.4) | 126 (2.9) | 172 (2.2) | |
| Clinical features | ||||
| Axillary temperature | <0.001 | |||
| <36°C | 3553 (29) | 1358 (31) | 2195 (28) | |
| 36–37.5°C | 4692 (38) | 1711 (39) | 2981 (38) | |
| >37.5°C | 3948 (32) | 1318 (30) | 2630 (34) | |
| Respiratory rate/min† | ||||
| Bradypnoea | 540 (4.4) | 188 (4.3) | 352 (4.5) | 0.56 |
| Normal | 7333 (60) | 2647 (60) | 4686 (60) | |
| Tachypnoea | 4158 (34) | 1490 (34) | 2668 (34) | |
| Missing | 240 (2.0) | 96 (2.2) | 144 (1.8) | |
| Heart rate/min‡ | ||||
| Bradycardia | 396 (3.2) | 158 (3.6) | 238 (3.0) | 0.11 |
| Normal | 8162 (67) | 2910 (66) | 5252 (67) | |
| Tachycardia | 3667 (30) | 1331 (30) | 2336 (30) | |
| Missing | 46 (0.4) | 22 (0.5) | 24 (0.3) | |
| Hypoxia§ | 2668 (22) | 932 (21) | 1736 (22) | 0.19 |
| Lower chest wall indrawing | 5562 (45) | 2051 (46) | 3511 (45) | 0.13 |
| Wheeze | 112 (0.9) | 46 (1.0) | 66 (0.8) | 0.41 |
| Stridor | 62 (0.5) | 19 (0.4) | 43 (0.6) | 0.48 |
| Breathing difficulty | 5966 (49) | 2172 (49) | 3794 (48) | 0.44 |
| Cyanosis | 560 (4.6) | 210 (4.8) | 350 (4.5) | 0.54 |
| Capillary refill >2 s | 301 (2.6) | 105 (2.4) | 196 (2.5) | 0.81 |
| Temperature gradient | 710 (5.8) | 258 (5.8) | 452 (5.8) | 0.73 |
| Weak pulse | 463 (3.8) | 157 (3.6) | 306 (3.9) | 0.05 |
| Lethargy | 971 (7.9) | 325 (7.4) | 646 (8.2) | 0.15 |
| Impaired consciousness¶ | 792 (6.5) | 250 (5.7) | 542 (6.9) | 0.007 |
| Bulging fontanel | 111 (0.9) | 32 (0.7) | 79 (1.0) | 0.21 |
| Stiff neck | 48 (0.4) | 10 (0.2) | 38 (0.5) | 0.05 |
| Convulsions | 689 (5.6) | 197 (4.5) | 492 (6.3) | <0.001 |
| Sunken eyes | 134 (1.1) | 44 (1.0) | 90 (1.2) | 0.44 |
| Reduced skin turgor | 308 (2.5) | 97 (2.2) | 211 (2.7) | 0.19 |
| Pallor | 633 (5.2) | 221 (5.0) | 412 (5.3) | 0.55 |
| Laboratory features | ||||
| Meningitis** | 98 (0.8) | 33 (0.8) | 65 (0.8) | 0.87 |
| Haemoglobin (<110 g/L)†† | 1207 (9.8) | 476 (11) | 731 (9.3) | 0.02 |
| HIV antibody positive | 441 (3.6) | 142 (3.2) | 299 (3.8) | 0.11 |
| Malaria slide positive | 5 (0.04) | 4 (0.09) | 1 (0.01) | 0.02 |
| Bacteraemia | 590 (4.8) | 170 (3.9) | 420 (5.4) | <0.001 |
| White blood cells (109cells/L)‡‡ | ||||
| <4 | 134 (1.1) | 54 (1.2) | 80 (1.0) | <0.001 |
| 4–20 | 8738 (71) | 3228 (73) | 5510 (70) | |
| >20 | 2202 (18) | 690 (16) | 1512 (19) | |
| Unavailable | 1197 (9.8) | 449 (10) | 748 (9.5) | |
| Platelets (109 /L)§§ | ||||
| <150 | 1615 (13) | 586 (13) | 1029 (13) | 0.59 |
| ≥150 | 9455 (77) | 3387 (77) | 6068 (77) | |
| Unavailable | 1201 (9.8) | 448 (10) | 753 (9.6) | |
| Blood glucose (mmols/L) | ||||
| <2.6 | 2479 (20) | 882 (20) | 1597 (20) | 0.29 |
| 2.6–7.0 | 5086 (41) | 1875 (42) | 3211 (41) | |
| >7.0 | 688 (5.6) | 231 (5.2) | 457 (5.8) | |
| Unavailable | 4018 (33) | 1433 (32) | 2585 (33) |
*Eligible admissions were young infants aged <60 days admitted from 2009 to 2019.
†Tachypnoea: respiratory rate ≥60 breaths/min, bradypnoea: respiratory rate <30 breaths/min.
‡Tachycardia: heart rate >160 beats/min, bradycardia: heart rate <100 beats/min.
§Hypoxia: oxygen saturation <90%.
¶Impaired consciousness level if ‘prostrate’ or ‘unconscious’.
**Meningitis: positive CSF culture, or positive CSF microscopy, or positive CSF antigen test, or elevated CSF WBC count (≥0.02x 10⁹ cells/Lin young infants aged 0–28 days OR, ≥0.01x109 cells/L in young infants aged 29–59 days) PLUS a positive blood culture for a known pathogen.
††Anaemia: haemoglobin <110g/L.
‡‡Normal values WBC 4–20×109 cells/L, leucopenia WBC <4×109cells/L, leucocytosis WBC >20×109 cells/L.
§§Normal values platelets ≥150×10⁹ /L, thrombocytopenia <150×10⁹/L.
CSF, cerebrospinal fluid; KCH, Kilifi County Hospital; KHDSS, Kilifi Health and Demographic Surveillance System; MUAC, mid-upper arm circumference; WBC, white blood cell.