Vitamin B6 status of children with sickle cell disease.
OBJECTIVE
In vitro, vitamin B(6) has antisickling properties, but the effect of vitamin B status on the health of children with sickle cell disease-SS (SCD-SS) is not well described. The purpose of this study was to assess vitamin B(6) status of children with SCD-SS ages 3 to 20 years and determine its relationship to growth, dietary intake, and disease severity.


METHODS
Vitamin B(6) status was assessed by serum pyridoxal 5-phosphate (PLP) concentration in subjects with SCD-SS and by urinary 4-pyridoxic acid (4-PA) concentration in other subjects with SCD-SS and healthy control children. Concentration of PLP was compared with anthropometric measures of growth and nutritional status, dietary intake, hematologic indices, and frequency of SCD-related illness.


RESULTS
The PLP concentration of subjects with SCD-SS was 15.6 +/- 15.2 nmol/L. Seventy-seven percent had a PLP concentration below the deficiency criterion (20 nmol/L) suggested by the Dietary Reference Intakes (1998). Controlling for alkaline phosphatase, age, and gender, PLP concentration was associated positively with weight, body mass index, and arm circumference -scores and negatively with reticulocyte count. Urinary 4-PA was lower in children with SCD-SS versus controls, although 4-PA/creatinine values did not differ between groups.


CONCLUSIONS
Children with SCD-SS had apparently low serum PLP concentrations in the absence of excess vitamin B(6) excretion, suggesting low vitamin B(6) status. Low serum PLP concentration was associated with indicators of poor nutritional status and may be related to increased hemolysis in children with SCD-SS.
Nelson
Melissa C
MC
Division of Gastroenterology and Nutrition, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104-4399, USA.
Zemel
Babette S
BS
Kawchak
Deborah A
DA
Barden
Elizabeth M
EM
Frongillo
Edward A
EA
Coburn
Stephen P
SP
Ohene-Frempong
Kwaku
K
Stallings
Virginia A
VA
D000293:Adolescent; D000328:Adult; D000410:Alanine Transaminase / Q000378:metabolism; D000469:Alkaline Phosphatase / Q000378:metabolism; D000755:Anemia, Sickle Cell / Q000453:epidemiology / Q000378:metabolism*; D000886:Anthropometry; D001219:Aspartate Aminotransferases / Q000378:metabolism; D015415:Biomarkers / Q000032:analysis; D002648:Child; D002664:Child Nutritional Physiological Phenomena; D002675:Child, Preschool; D004032:Diet; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D009752:Nutritional Status; D015143:Philadelphia / Q000453:epidemiology; D011732:Pyridoxal Phosphate / Q000097:blood; D011735:Pyridoxic Acid / Q000652:urine; D025101:Vitamin B 6 / Q000378:metabolism*
D015415:Biomarkers; D011735:Pyridoxic Acid; D011732:Pyridoxal Phosphate; D025101:Vitamin B 6; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase; D000469:Alkaline Phosphatase