AUTHOR=Williams Brock A. , Mayer Cara , McCartney Heather , Devlin Angela M. , Lamers Yvonne , Vercauteren Suzanne M. , Wu John K. , Karakochuk Crystal D. 

TITLE=Detectable Unmetabolized Folic Acid and Elevated Folate Concentrations in Folic Acid-Supplemented Canadian Children With Sickle Cell Disease

JOURNAL=Frontiers in Nutrition

VOLUME=8

YEAR=2021

URL=https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2021.642306

DOI=10.3389/fnut.2021.642306

ISSN=2296-861X

ABSTRACT=<p>Sickle cell disease (SCD) is an inherited hemoglobinopathy caused by a variant (rs344) in the <italic>HBB</italic> gene encoding the β-globin subunit of hemoglobin. Chronic hemolytic anemia and increased erythropoiesis and RBC turnover in individuals with SCD can result in increased needs for folate and other B-vitamins. We assessed B-vitamin status, and the distribution of folate forms, including unmetabolized folic acid (UMFA), in Canadian children with SCD supplemented with 1 mg/d folic acid (current routine practice). Non-fasted serum and plasma samples were analyzed for concentrations of folate, and vitamins B-2, B-6, and B-12. Eleven individuals (45% male; SCD type: HbSS <italic>n</italic> = 8, HbSC <italic>n</italic> = 2, HbSβ<sup>0</sup>-Thal <italic>n</italic> = 1), with a median (IQR) age of 14 (7, 18) years, were included. Total folate concentrations were 3–27 times above the deficiency cut-off (10 nmol/L), and 64% of children had elevated folate levels (&gt;45.3 nmol/L). UMFA (&gt;0.23 nmol/L) was detected in all children, and 36% of participants had elevated levels of UMFA (&gt;5.4 nmol/L). All children were vitamin B-12 sufficient (&gt;150 pmol/L), and the majority (55%) had sufficient B-6 status (&gt;30 nmol/L). Among this sample of Canadian children with SCD, there was limited evidence of B-vitamin deficiencies, but UMFA was detectable in all children.</p>