DIMINISHED VITAMIN-B-12 LEVELS IN PATIENTS WITH SEVERE SICKLE-CELL DISEASE

Objective. The aim of this study was to estimate the levels of vitamin B-12 in patients with severe sickle cell disease compared to normal controls. Complete blood count, iron studies and vitamin B-12 levels were obtained in 85 consecutive patients with severe sickle cell disease (56 males, 29 females, aged 14-49 years) and 100 healthy blood donors (67 males, 33 females, aged 17-60 years) as a normal control group. Results. Thirty-seven of the 85 patients (43.5%) had serum vitamin B-12 levels below normal values (mean 84.3+/-28.7, range 7-145 pmol L(-1)) without macrocytosis or hypersegmented neutrophils. The mean level of vitamin B-12 in the remaining 48 patients (56.5%) was normal (mean 233.3+/-73.9, range 152-435 pmol L(-1)) which is below the mean of normal control levels (mean 327.7+/-168.7, range 178-897 pmol L(-1)). Patients with low B-12 achieved a significant symptomatic improvement when treated with vitamin B-12, 1 mg intramuscularly weekly for 12 weeks when compared with patients with normal B-12 levels. Conclusion. We conclude that many patients with severe sickle cell disease may suffer from unrecognized vitamin B-12 deficiency.