Relationship between ultrasound-measured spleen, liver and anthropometry of children living in a rural community in southwest Nigeria: a cross-sectional study.

BACKGROUND: Ultrasonography is noninvasive, relatively inexpensive and useful for resource-poor settings. US spleen and liver sizes have been observed to differ among populations, so there is a need for reference values for different geographic populations. OBJECTIVE: To describe the sizes of the spleen and liver of children living in a rural community in southwest Nigeria and assess the relationship between these measurements and the children's anthropometry. MATERIALS AND METHODS: We conducted a community-based cross-sectional study among 358 apparently healthy children ages 1-14 years. We obtained the participants' weights, heights, body mass index and body surface area. They underwent US imaging to obtain longitudinal measurements of their spleen and liver. We used independent t-test to compare means, and linear regression analysis to assess relationships between continuous data. The significance level was set as P < 0.05. RESULTS: There were more girls (181; 50.6%). Most children were ages 1-5 years (172; 48.0%). The body surface area had significantly strong positive relationships with US spleen size (r = 0.769; R2 = 0.592; P < 0.0001) and US liver size (r = 0.819; R2 = 0.671; P < 0.0001) but body mass index had weak positive relationships. CONCLUSION: This study contributes to data on US spleen and liver sizes of Nigerian children. The findings buttress observations that body surface area strongly correlates with US spleen and liver measurements. It is recommended that more studies be conducted among Nigerian children to generate a robust pool of data that are useful for creating homogeneous formulae to ease interpretation of US measurements of these intraabdominal organs.

Towards malaria control in Nigeria: implications of the malaria parasite rate and spleen rate among children living in a rural community in southwest Nigeria.

BACKGROUND: The World Health Organization prioritizes malaria surveillance for accurate tracking of progress of intervention programmes. The malaria parasite rate (PR) and spleen rate (SR) are economical surveillance tools. There has been a global decline in the burden of malaria over the last decade, but most African countries, like Nigeria, have a slow rate of decline. There is a need for adequate malaria surveillance to guide malaria control strategies and policymaking. METHODS: A community-based cross-sectional study was conducted among 363 children ages 1-15 y in rural southwest Nigeria. The participants' PR was determined by microscopy and the SR was determined by palpation and ultrasonography. The associations between PR and SR and other covariates were assessed. RESULTS: The PR was 26.7% and the SR was 12.9%. There was no significant association between PR or SR across age groups, but low social class was significantly associated with PR (55 [33.5%], p=0.004) and SR (29 [17.3%], p=0.013). The odds of having splenomegaly doubled with malaria parasitaemia (odds ratio 2.03 [95% confidence interval 1.06 to 3.88). CONCLUSIONS: The PR and SR suggest that the study area is meso-endemic. The PR in the study area was almost equal across age groups; our findings suggest there may be a need for policy review to plan malaria intervention programmes and include older children, not just children <5 y of age. Routine malaria surveillance using simple tools such as the PR and SR are necessary for reviewing malaria control programmes in the community.