Asymptomatic malaria infection among children with Sickle Cell Anaemia: The role of IL-10 and possible predisposing factors
Introduction: malaria is a major contributor to morbidity and mortality of under five children with Sickle cell anaemia (SCA) in malaria endemic regions. Asymptomatic malaria infection carriers constitute a reservoir for malaria transmission which could be detrimental in patients with SCA despite the use of malaria chemoprophylaxis. This study, therefore, determined the prevalence of asymptomatic malaria, levels of IL-10 and association between asymptomatic malaria infection, possible predisposing factors and levels of IL-10 in children living with Sickle cell anaemia. Methods: a case-control study was conducted involving children aged 2-16 years; 60 children with SCA in steady state and 40 control subjects with HbAA. Blood samples were collected by veni-puncture and asymptomatic malaria infection was detected using Rapid diagnostic test (RDT), Giemsa-stained thin and thick blood films and nested Polymerase Chain Reaction (PCR) technique. Serum IL-10 levels were determined using ELISA method. Results: among patients with SCA, two samples (3.3%) were positive for RDT, three samples (5%) were positive for microscopy, and four samples (6.7%) were positive for nested PCR technique. None of the patients in the control group was positive for Plasmodium falciparum detection using the three diagnostic methods. The mean ± (SD) of IL-10 levels in SCA patients with asymptomatic malaria (9.14(1.08)pg/ml) was significantly higher than those without asymptomatic malaria (4.8(2.62) pg/ml) (P<0.0001). Conclusion: this study demonstrated accurate diagnosis of asymptomatic malaria infection using PCR-based technique. We established that asymptomatic malaria is present in steady state SCA children and is associated with elevated IL-10 levels.