Apparent vitamin B6 deficiency in sickle cell anemia

Abstract

In 16 patients with sickle cell anemia, plasma pyridoxal phosphate (PLP) concentrations were significantly lower than in 16 controls (p < 0.0001) whereas sickle cell anemia erythrocyte PLP concentrations were significantly elevated (p < 0.0005), possibly reflecting a greater affinity of PLP to the sickle Hb β chain compared to the normal β chain. Oral supplementation of five patients with 50 mg pyridoxine twice daily for 2 months resulted in increased plasma and erythrocyte PLP levels and a slight, but not significant, increase in erythrocyte cell number, Hb, concentration, and hematocrit. In one subject there was also a reduction in the frequency and duration of painful crises and a virtual elimination of hospitalizations for the treatment of the painful crises. Since pyridoxal and PLP have been shown to have antisickling properties in vitro, these studies suggest that pyridoxine supplementation may also be of therapeutic benefit in vivo in sickle cell anemia.