Characteristics of the study subjects
Table (1) shows that 50.0% and 55.7% of malaria-infected patients were females and older than 30 years, with a median age of 33.0 ± 22.0 years (range: 1–47). On the other hand, 52.0% and 53.0% of malaria-negative subjects were females and aged older than 30 years, with a median age of 31.0 ± 26.0 years (range: 1–67). The median density of P. falciparum was 677.5 600.1 parasites/µl of blood (range: 26–10040). The majority of P. falciparum-infected patients (64.6%) showed a low-level parasitemia, while only 1.0% of patients showed a high-level parasitemia.
Table 1
Characteristics of malaria patients and malaria-negative subjects in Kosti city of the White Nile State, Sudan (2018)
Characteristics
|
P. falciparum-infected patients (N = 192)
|
Malaria-negative subjects (N = 200)
|
n (%)
|
n (%)
|
Gender
|
|
|
Male
|
96 (50.0)
|
96 (48.0)
|
Female
|
96 (50.0)
|
104 (52.0)
|
Age (years)
|
|
|
≤30
|
85 (44.3)
|
94 (47.0)
|
>30
|
107 (55.7)
|
106 (53.0)
|
Median ± IQR
|
33.0 ± 22.0
|
31.0 ± 26.0
|
Range
|
1–47
|
1–67
|
P. falciparum density (parasites/μl)
|
|
N/A
|
Median ± IQR
|
677.5 ± 600.1
|
Range
|
26–10040
|
Parasitaemia level
|
|
N/A
|
Low
|
124 (64.6)
|
Moderate
|
66 (34.4)
|
High
|
2 (1)
|
IQR, interquartile range; N/A, not applicable.
Comparison of RBC indices between P. falciparum-infected patients and malaria-negative individuals
The median indices of Hb concentration, RBC count, MCH and MCHC were significantly lower in P. falciparum-infected patients compared to malaria-negative individuals. In contrast, MCV was not significantly different between both groups (Table 2).
Table 2
RBC indices in P. falciparum-infected patients and malaria-negative subjects in Kosti city of the White Nile State, Sudan (2018)
Indices
|
P. falciparum-infected patients (n = 192)
|
Malaria-negative subjects (n = 200)
|
P-value
|
Median ± IQR
|
Hb concentration (g/dL)
|
11.6 ± 3.8
|
14.0 ± 2.2
|
<0.001
|
RBC count (×1012/L)
|
4.5 ± 1.0
|
4.7 ± 0.7
|
0.001
|
MCV (fL)
|
86.0 ± 12.0
|
87.0 ± 9.8
|
0.452
|
MCH (pg)
|
28.5 ± 3.0
|
29.0 ± 2.8
|
<0.001
|
MCHC (g/dL)
|
31.5 ± 3.0
|
32.5 ± 2.5
|
0.037
|
IQR, interquartile range; Hb, hemoglobin; RBC, red blood cell; MCV, mean corpuscular volume; MCH, mean corpuscular hemoglobin; MCHC, mean corpuscular hemoglobin concentration.
Comparison of WBC and platelet indices between P. falciparum-infected patients and malaria-negative individuals
The median total WBC count was higher in P. falciparum-infected patients compared to malaria-negative individuals, but the difference was not statistically significant. The median percentages of neutrophils and lymphocytes were significantly lower in P. falciparum-infected patients. Meanwhile, the median platelet count was significantly lower in P. falciparum-infected patients compared to malaria-negative individuals (Table 3).
Table 3
WBC and platelet indices in P. falciparum-infected patients and malaria-negative subjects in Kosti city of the White Nile State, Sudan (2018)
Indices
|
P. falciparum-infected patients (n = 192)
|
Malaria-negative subjects (n = 200)
|
p-value
|
Median ± IQR
|
Total WBC count (×109/L)
|
7.0 ± 4.0
|
6.5 ±3.00
|
0.275
|
Neutrophil count (%)
|
37.0 ± 11.0
|
38.0 ± 8.0
|
0.001
|
Lymphocyte count (%)
|
24.0 ± 12.0
|
26.0 ± 18.0
|
0.004
|
Monocyte count (%)
|
5.0 ± 2.0
|
5.0 ± 2.0
|
0.021
|
Platelet count (×109/L)
|
140.0 ± 38.0
|
230.0 ± 115.0
|
<0.001
|
WBC, white blood cell; IQR, interquartile range.
Comparison of hematological cytopenias between P. falciparum-infected patients and malaria-negative subjects
The prevalence of anemia was significantly higher among patients infected with P. falciparum compared to malaria-negative subjects (60.4% vs. 29.5%, respectively), where P. falciparum-infected patients were 3.6-fold more likely to have anemia. Meanwhile, the prevalence of thrombocytopenia was significantly higher among patients infected with P. falciparum compared to malaria-negative subjects (72.4% vs. 5.0%, respectively), where P. falciparum-infected patients were approximately 50-fold more likely to be thrombocytopenic. In contrast, there was no statistically significant difference between both groups regarding leucopenia (Table 4).
Table 4
Hematological cytopenias among patients with falciparum malaria and malaria-negative subjects in in Kosti city of the White Nile State, Sudan (2018)
Hematological abnormality
|
P. falciparum-infected patients
(N = 192)
|
Malaria-negative subjects
(N = 200)
|
OR (95% CI)
|
P-value
|
n (%)
|
n (%)
|
Anemia
|
116 (60.4)
|
59 (29.5)
|
3.6 (2.4–5.5)
|
<0.001
|
Thrombocytopenia
|
139 (72.4)
|
10 (5.0)
|
49.8 (24.5–101.4)
|
<0.001
|
Leucopenia
|
24 (12.5)
|
22 (11.6)
|
0.9 (0.5–1.6)
|
0.754
|
OR, odds ratio; CI, confidence interval.