Table 2.
Factors associated with methemoglobinemia in a pediatric fever cohort
| MHb ≤2 % N = 1364 (66 %) |
MHb >2 % N = 689 (34 %) |
Bivariate OR (95 % CI) |
P-value | Multivariate OR (95 % CI) |
P-value | |
|---|---|---|---|---|---|---|
| Demographic characteristics | ||||||
| Age, months | 17 [9, 26] | 18 [9, 30] | 1.00 (1.00, 1.01) | 0.268 | 1.00 (1.00, 1.01) | 0.370 |
| Age <6 months | 98 (7.2) | 53 (7.7) | 1.08 (0.76, 1.52) | 0.677 | ||
| Male (%) | 734 (54.4) | 382 (56.1) | 1.07 (0.89, 1.29) | 0.461 | ||
| Clinical findings at admission | ||||||
| Fever (≥38o C) | 402 (39.1) | 276 (27.6) | 0.59 (0.49, 0.72) | <0.001 | 0.74 (0.60, 0.92) | 0.005 |
| Underweight, <-2 WAZ | 303 (22.6) | 150 (22.3) | 0.97 (0.77, 1.21) | 0.775 | ||
| Systolic BP | 105.5 (15.3) | 104.2 (7.0) | 0.99 (0.99, 1.00) | 0.094 | ||
| Diastolic BP | 58.4 (13.3) | 55.6 (13.4) | 0.98 (0.98, 0.99) | <0.001 | 0.99 (0.98, 1.00) | 0.130 |
| Age-specific elevated respiratory rate, per min | 693 (52.7) | 398 (59.8) | 1.34 (1.11, 1.62) | 0.002 | ||
| Deep breathing | 282 (20.7) | 213 (31.0) | 1.72 (1.40, 2.12) | <0.001 | ||
| Vomiting | 399 (29.3) | 272 (39.6) | 1.58 (1.30, 1.91) | <0.001 | 1.36 (1.09, 1.70) | 0.007 |
| Diarrhea | 424 (31.2) | 176 (25.6) | 0.82 (0.64, 0.) | 0.008 | 0.82 (0.64, 1.04) | 0.107 |
| Blantyre coma score | ||||||
| 0 1 2 3 4 5 |
21 (1.6) 13 (1.0) 22 (1.6) 45 (3.4) 63 (4.7) 1173 (87.7) |
26 (3.9) 9 (1.3) 25 (3.7) 41 (6.1) 48 (8.6) 514 (76.4) |
0.78 (0.71, 0.85) | <0.001 | ||
| Capillary refill time | ||||||
| < 2 seconds | 1180 (89.5) | 515 (77.0) | ||||
| 2- <3 sec | 90 (6.8) | 102 (15.2) | ||||
| ≥ 3 sec | 49 (3.7) | 49 (3.7) | 1.81 (1.52, 2.16) | <0.001 | 1.36 (1.11, 1.66) | 0.003 |
| Pretreatment with antibiotics | 428 (31.6) | 240 (35.5) | 1.19 (0.98, 1.45) | 0.079 | ||
| Pretreatment with sulfadoxine pyremethamine | 16 (1.2) | 14 (2.1) | 1.76 (0.85, 3.63) | 0.125 | ||
| Subcostal retractions | 236 (17.3) | 172 (25.0) | 1.59 (1.27, 1.98) | <0.001 | ||
| Laboratory test results at admission | ||||||
| Lactate, mmol/L | 2.5 [1.8, 4.0] | 3.4 [2.2, 8.5] | 1.14 (1.11, 1.16) | <0.001 | 1.08 (1.05, 1.11) | <0.001 |
| Glucose, mmol/L | 7.1 (2.3) | 7.9 (3.3) | 1.11 (1.07, 1.15) | <0.001 | ||
| Oxygen saturation (Sp02) | 98 [96, 100] | 98 [95, 99] | 0.97 (0.95, 0.99) | 0.015 | ||
| Severe anemia, Hb < 5 g/dL or pallor | 182 (13.3) | 233 (33.8) | 3.32 (2.66, 4.14) | <0.001 | 1.99 (1.51, 2.61) | <0.001 |
| Suspected hemoglobinopathy | 41 (3.0) | 41 (6.0) | 2.04 (1.31, 3.18) | 0.002 | 1.97 (1.17, 3.32) | 0.011 |
| Lab-confirmed malaria1 | 883 (64.8) | 498 (72.5) | 1.43 (1.17, 1.74) | 0.001 | 1.34 (1.07, 1.69) | 0.011 |
Mean (SD) for normally distributed variables. Median [IQR] for non-normally distributed variables. Number (%) for categorical variables
1Positive by microscopy or RDT (HRP2/pLDH or pLDH)
Factors significantly associated with methemoglobinemia in bivariate or multivariate analysis in bold