Specific Cytokine Assay for the Diagnosis and Prognosis of Malaria in Adult Patients in a Holoendemic Lagos, Nigeria

Background: During Plasmodium falciparum infection, cytokines are said to be elevated in the peripheral blood and may contribute to parasite clearance and also, likely to be responsible for many of the symptoms and pathological changes observed during malaria disease. Aim: this study evaluated specific cytokines as possible tool for diagnosis and prognosis of uncomplicated malaria in adult patients. Methods: Prospective 147 apparently malaria adult patients were microscopically screened and parasite load quantified. Blood donors (n=30) were used as control group A (CA) and parasite negative patients (n=26) as control group B (CB). The study took place between Aug. and Dec. 2014. The Cytokines (IL 12 and IL 18) levels were measured using ELIZA method. The data generated were analyzed using SPSS (15) two step cluster analysis for categorical variable and ANOVA excel single factor package was used to test significance differences between test and control groups. Results: Only 34/147 (23.1 %) were malarial positive, with mean parasite density of 2,384 ± 26,191 parasites/μl. Uncomplicated adult malaria had lower (30.2 ± 56.7ng/L) IL-12 concentration when compared with the controls and higher (30.9 ± 36.5ng/L) IL-18 for CA and not for CB. The mean analyses of variance between the groups were not statistically significant at 95% confidence interval: IL- 12 T versus (vs.) CA, P=0.899; IL-12 T vs. CB, P=0.600. For cytokine IL-18 (T) vs. CA, P=0.674; IL-18 (T) vs. CB, P=0.509. There was no significant difference between the two control groups: IL -12 CA vs. CB, P=0.7696 and IL-18 CA vs. CB, P=0.599. Conclusion: Excluding the outliers, the low production of IL-12 with higher level of IL-18 by majority of the patients indicates protective characteristics of pro-inflammatory cytokines studied; this is prognostic in nature. However, the report of mean ratio (IL-12/lL18) of 0.886, 0.955 and 0.916 ng/L for the T, CA and CB respectively were not discriminatory and therefore not diagnostic.