Relationship between Neutrophil-lymphocyte Ratio, Monocyte-Lymphocyte Ratio and Parasitaemia in Determining the Severity of Malaria Infection in Children Immune cell ratios and parasitaemia in children

Abstract

Background: Malaria often presents as a febrile illness which causes noticeable changes in the haematological parameters. There were inconsistencies with the report on the relationship between the haematological parameters and level of parasitaemia. Objectives: This study therefore aimed to ascertain the correlation between the level of parasites in the blood, the neutrophil-lymphocyte ratio (NLR) and the monocyte –lymphocyte ratio (MLR) as a measure of severity of malaria infection. Materials and Methods: This was a cross-sectional study involving three groups of children: complicated malaria, uncomplicated malaria and healthy controls. Haematological profile was done using a haematology auto-analyzer. Parasite density was done using microscopy. The study's data was analyzed utilizing the Statistical product and services solutions (SPSS) version 25. Results: The mean level of NLR and MLR was higher in children with complicated than uncomplicated malaria (p = 0.023); and normal healthy children (p < 0.001). About half 46.3% of the children in the complicated group had parasitaemia in the range of >100-5000 parasites /µL while 47.5% of children in the uncomplicated group had parasitaemia in the range of 500-1000 parasites /µL. The mean parasite density for complicated and uncomplicated groups were 4542.9 and 1666.6/ µL respectively. A positive significant correlation was seen between NLR, MLR and the parasite density in the complicated malaria group {r= 0.623, P=0.022). Conclusion: The NLR and MLR correlate positively with the level of parasitaemia. Consequently, these ratios could serve as a surrogate for the level of parasitaemia and hence the severity of malaria in children.