Table 6. Comparative analysis of clinical presentation, lab results and diagnoses at day zero.
LD versus HD (low versus high-density parasitemia).
| HD parasitemia sd-mRDT+/us-qPCR+ |
LD parasitemia sd-mRDT-/us-qPCR+ |
LD versus HD parasitemia | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PREVALENCE | CRUDE BIVARIATE ANALYSIS | ADJUSTED (Age) | ||||||||||
| Signs and Symptoms | % | Total = 198 | % | Total = 76 | RRcrude | 95% CI | p-value | RRadj | 95% CI | p-value | ||
| Danger signs present | 2.0 | 4 | 1.3 | 1 | 0.7 | (0.1–2.4) | 0.7 | 0.4 | (0.1–2.1) | 0.4 | ||
| Respiratory distress | 0.5 | 1 | 1.3 | 1 | 1.8 | (0.2–3.4) | 0.5 | 1.3 | (0.1–3.2) | 0.8 | ||
| Cough | 44.4 | 88 | 39.5 | 30 | 0.9 | (0.6–1.3) | 0.5 | 0.7 | (0.5–1.1) | 0.2 | ||
| Pharyngitis | 1.0 | 2 | 1.3 | 1 | 1.2 | (0.2–3.0) | 0.8 | 1.0 | (0.1–2.9) | 1.0 | ||
| Abdominal pain | 12.6 | 25 | 6.6 | 5 | 0.6 | (0.2–1.2) | 0.2 | 1.1 | (0.5–2.0) | 0.9 | ||
| Loss of appetite | 2.5 | 5 | 3.9 | 3 | 1.6 | (0.4–2.6) | 0.5 | 1.3 | (0.4–2.7) | 0.6 | ||
| Vomit | 24.2 | 48 | 26.3 | 20 | 1.1 | (0.7–1.6) | 0.7 | 1.0 | (0.6–1.5) | 0.9 | ||
| Diarrhea | 8.1 | 16 | 14.5 | 11 | 1.5 | (0.9–2.3) | 0.12 | 1.3 | (0.7–2.1) | 0.4 | ||
| Fever only | 23.2 | 46 | 13.2 | 10 | 0.6 | (0.3–1.0) | 0.07 | ∼ | 0.6 | (0.3–1.1) | 0.09 | ∼ |
| FWSb | -- | -- | 43.4 | 33 | – | – | – | – | – | – | ||
| Lab results and measures | Mean | 95% CI | Mean | 95% CI | RRcrude | 95% CI | p-value | RRadj | 95% CI | p-value | ||
| Temperature (°C) | 39.0 | (38.8–39.1) | 38.3 | (38.1–38.5) | 0.4 | (0.3–0.5) | <0.001 | a | 0.4 | (0.3–0.6) | <0.001 | a |
| Preconsult fever duration | 1.7 | (1.5–1.8) | 1.3 | (1.1–1.5) | 0.7 | (0.6–1.0) | 0.02 | a | 0.7 | (0.6–1.0) | 0.06 | ∼ |
| Hemoglobin (g/dL) | 8.9 | (8.5–9.2) | 9.6 | (9.2–10.1) | 1.3 | (1.0–1.6) | 0.02 | a | 1.6 | (1.2–2.1) | 0.00 | a |
| Median | IQR | Median | IQR | RRcrude | 95% CI | p-value | RRadj | 95% CI | p-value | |||
| CRP (mg/L)e | 10.0 | (10.0-40.0) | 0.0 | (0.0-10.0) | 1.0 | (0.9–1.0) | 0.02 | a | 1.0 | (0.9–1.0) | 0.05 | a |
| PCT (ug/L) | 5.5 | (0.6-21.1) | 0.3 | (0.1-0.4) | 0.7 | (0.5–1.0) | 0.04 | a | 0.7 | (0.5–1.0) | 0.07 | ∼ |
| Diagnoses | % | Total = 198 | % | Total = 76 | RRcrude | 95% CI | p-value | RRadj | 95% CI | p-value | ||
| Anemia (moderate-to-severe)c | 74.0 | 77/104 | 56.5 | 26/46 | 0.6 | (0.3–1.0) | 0.04 | a | 0.3 | (0.1–0.7) | 0.001 | a |
| Sickle cell disease (HbSS)d | 14.9 | 13/87 | 10.0 | 4/40 | 0.7 | (0.3–1.5) | 0.5 | 0.7 | (0.3–1.6) | 0.5 | ||
| Sickle cell trait (HbAS)d | 0.0 | 0/87 | 0.0 | 0/40 | ||||||||
| Malnutrition | 5.6 | 11 | 9.2 | 7 | 1.4 | (0.7–2.3) | 0.3 | 1.2 | (0.6–2.1) | 0.6 | ||
| Severe malnutrition | 1.5 | 3 | 5.3 | 4 | 2.1 | (0.8–3.1) | 0.1 | 1.6 | (0.5–2.9) | 0.3 | ||
| Severe illness | 11.6 | 23 | 11.8 | 9 | 1.0 | (0.5–1.7) | 1.0 | 1.1 | (0.6–1.8) | 0.8 | ||
| URTI | 5.6 | 11 | 13.3 | 10/75 | 1.8 | (1.0–2.7) | 0.04 | a | 1.5 | (0.8–2.4) | 0.2 | |
| Pneumonia | 23.7 | 47 | 13.2 | 10 | 0.6 | (0.3–1.0) | 0.06 | ∼ | 0.6 | (0.3–1.1) | 0.08 | ∼ |
| HIV | 0.5 | 1/185 | 1.5 | 1/68 | 1.9 | (0.2–3.5) | 0.5 | 1.7 | (0.2–3.5) | 0.6 | ||
| Suspected viral infection | 0.5 | 1 | 42.1 | 32 | 5.3 | (4.4–5.5) | <0.001 | a | 5.3 | (4.4–5.5) | <0.001 | a |
| Suspected bacterial infection | 0.5 | 1 | 1.3 | 1 | 1.8 | (0.2–3.4) | 0.5 | 2.5 | (0.3–3.6) | 0.3 | ||
ap < 0.05 and considered as statistically significant
bFWS is diagnosed using sd-mRDT, and it is thus not present in HD infection.
cModerate-to-severe anemia: Hb < 9 g/dL.
dHbSS only investigated in samples with sufficient blood volume (i.e., 40/78 LD, 87/198 HD, and 895/2,527).
eCRP was measured using a categorical quantitation test. Four categories exist: <10 mg/L, 10–40 mg/L, 40–80 mg/L, and >80 mg/L. The lower limit of this range is represented in the table. See S2 Table for the definition of severe illness and severe malnutrition.
CRP, C-reactive protein; FWS, fever without source; HbAS heterozygote, sickle cell trait; HbSS homozygote, sickle cell disease; HD, low-density Pf infection; HIV, human immunodeficiency virus; LD, low-density Pf infection; PCT, procalcitonin; RR, risk ratio; RRadj, adjusted RR; RRcrude, crude (unadjusted) RR; Sd-mRDT, standard malaria rapid diagnostic test; URTI, upper respiratory tract infection; us-qPCR, ultrasensitive quantitative PCR.