Clinical and Laboratory Factors Associated with Splenic Dysfunction Among Sickle Cell Disease Patients in a malaria endemic region

Background

Although loss of splenic function is the expected natural course for individuals with sickle cell disease (SCD), factors such as high HbF and coexistence of alpha thalassemia may ameliorate this process. We evaluated factors associated with two surrogate markers of spleen dysfunction - Howell-Jolly bodies (HJB) and argyrophilic inclusion (AI) red cell counts among SCD patients.

Methods

Cross-sectional data of 182 SCD patients (median age 11 years;1- 45 years) and 102 normal controls (median age 12 years;1-32 years) were evaluated. Blood tests including full blood count, serum chemistry and HPLC were performed. The HJB and AI red cell counts were performed on peripheral blood smears.

Results

The percentages of HJB- and AI- red cells rose significantly with increasing age in the SCD group. On regression analysis, frequency of HJB red cells associated positively with MCH (β = 0.289; P = 0.001) and negatively with HbF (β = -0.259; P = 0.002). The AI red cell counts also associated positively with MCH (β = 0.321; P=0.001) and negatively with HbF (β = -0.242; P = 0.020).

Conclusion

Data from this study indicates that the negative association of HbF with both markers of splenic dysfunction among our SCD patients residing in a malaria-endemic region is similar to findings elsewhere of its ameliorating effect on splenic dysfunction.