Storage related haematological and biochemical changes in Plasmodium falciparum infected and sickle cell trait donor blood.

Background: In sub-Saharan Africa where sickle cell trait (SCT) and malaria is prevalent, significant proportions of blood donors may be affected by one or more of these abnormalities. The haemato-biochemical properties of SCT and asymptomatic malaria in donor blood have not been evaluated. This study evaluated the haemato-biochemical impact of SCT and asymptomatic malaria infections in citrate-phosphate-dextrose-adenine (CPDA-1) stored donor blood units.

Methods: Fifty-milliliters of sterile CPDA-1 anti-coagulated blood were drained into the sample pouch attached to the main blood bag. Ten units each of sickle cell/malaria negative, sickle cell and malaria positive blood were analyzed. Baseline and weekly haematological profiling and week 1, 3 and 5 concentrations of plasma haemoglobin, % haemolysis, sodium, potassium and chloride and lactate dehydrogenase (LDH) were assayed. Differences between baseline and weekly data were determined using one-way analysis of variance (ANOVA) and Kruskal-Wallis test, whereas differences between baseline parameters and week 1-3 data pairs were determined using paired t-test. P -value < 0.05 was considered statistically significant.

Results: Storage of SCT and malaria infected blood affected all haematological cell lines. In the SCT donors, red blood cells (RBC) (4.75 × 1012 /L ± 1.43baseline to 3.49 × 1012 /L ± 1.09week-5 ), haemoglobin (14.45 g/dl ± 1.63baseline to 11.43 g/dl ± 1.69week-5 ) and haematocrit (39.96% ± 3.18baseline to 33.22% ± 4.12week-5 ) were reduced. In the asymptomatic malaria group, reductions were observed in RBC (5.00 × 1012 /L ± 0.75baseline to 3.72 × 1012 /L ± 0.71week-5 ), haemoglobin (14.73 g/dl ± 1.67baseline to 11.53 g/dl ± 1.62week-5 ), haematocrit (42.72% ± 5.16baseline to 33.38% ± 5.80week-5 ), mean cell haemoglobin concentration (35.48 g/dl ± 1.84baseline to 35.01 g/dl ± 0.64week-5 ) and red cell distribution width coefficient of variation (14.81% ± 1.54baseline to 16.26% ± 1.37week-5 ). Biochemically, whereas plasma LDH levels significantly increased in asymptomatic malaria blood donors (319% increase at week 5 compared to baseline), SCT blood donors had the most significant increase in plasma potassium levels at week 5 (382% increase). Sodium ions significantly reduced in SCT/malaria negative and sickle cell trait blood at an average rate of 0.21 mmol/L per day. Moreover, elevations in lymphocytes-to-eosinophils and lymphocytes-to-neutrophils ratios were associated with SCT and malaria positive blood whilst elevation lymphocytes-to-basophils ratio was exclusive to malaria positive blood.

Conclusion: Severe storage lesions were significant in SCT or malaria positive donor blood units. Proper clinical evaluation must be done in prospective blood donors to ensure deferral of such donors.