Biomaterial Database

Extremely low serum pyridoxal 5'-phosphate in children with familial hypophosphatemic rickets. 1991

R D Reynolds, and R S Lorenc, and E Wieczorek, and E Pronicka

Vitamin and Mineral Nutrition Laboratory, Beltsville Human Nutrition Research Center, US Department of Agriculture, MD 20705.

The apparent vitamin B-6 status of 31 children with familial hypophosphatemic rickets (FHR) was determined. All children had alkaline phosphatase activity that was high-normal to elevated for their ages. A sensitive assay for pyridoxal 5'-phosphate (PLP) indicated that 15 of the 31 children had an undetectable (less than 0.2 nmol/L) concentration of the vitamer--the lowest values yet reported in human serum. The 16 remaining children had concentrations of the vitamer so low that they indicated a potential severe vitamin B-6 deficiency. However, none of the children had ever presented with any of the classical vitamin B-6-deficiency symptoms. Treatment of three additional FHR children with 100 mg pyridoxine.HCl/d resulted in a moderate and transient elevation of their serum PLP concentrations, a dramatic elevation of their erythrocyte PLP concentrations, and no improvement in clinical condition. Serum or plasma PLP concentrations are an inappropriate index for determining vitamin B-6 status in people with FHR and perhaps in others with elevated alkaline phosphatase activity.

UI	MeSH Term	Description	Entries
D007015	Hypophosphatemia, Familial	An inherited condition of abnormally low serum levels of PHOSPHATES (below 1 mg/liter) which can occur in a number of genetic diseases with defective reabsorption of inorganic phosphorus by the PROXIMAL RENAL TUBULES. This leads to phosphaturia, HYPOPHOSPHATEMIA, and disturbances of cellular and organ functions such as those in X-LINKED HYPOPHOSPHATEMIC RICKETS; OSTEOMALACIA; and FANCONI SYNDROME.	Diabetes, Phosphate,Familial Hypophosphatemia,Hyperphosphaturia,Phosphate Diabetes,Phosphaturia,Familial Hypophosphatemias,Hypophosphatemias, Familial
D008297	Male		Males
D010710	Phosphates	Inorganic salts of phosphoric acid.	Inorganic Phosphate,Phosphates, Inorganic,Inorganic Phosphates,Orthophosphate,Phosphate,Phosphate, Inorganic
D011732	Pyridoxal Phosphate	This is the active form of VITAMIN B 6 serving as a coenzyme for synthesis of amino acids, neurotransmitters (serotonin, norepinephrine), sphingolipids, aminolevulinic acid. During transamination of amino acids, pyridoxal phosphate is transiently converted into pyridoxamine phosphate (PYRIDOXAMINE).	Pyridoxal 5-Phosphate,Pyridoxal-P,Phosphate, Pyridoxal,Pyridoxal 5 Phosphate,Pyridoxal P
D011736	Pyridoxine	The 4-methanol form of VITAMIN B 6 which is converted to PYRIDOXAL PHOSPHATE which is a coenzyme for synthesis of amino acids, neurotransmitters (serotonin, norepinephrine), sphingolipids, aminolevulinic acid. Although pyridoxine and Vitamin B 6 are still frequently used as synonyms, especially by medical researchers, this practice is erroneous and sometimes misleading (EE Snell; Ann NY Acad Sci, vol 585 pg 1, 1990).	Pyridoxin,Pyridoxine Hydrochloride,Pyridoxol,Pyridoxol Hydrochloride,Rodex
D002648	Child	A person 6 to 12 years of age. An individual 2 to 5 years old is CHILD, PRESCHOOL.	Children
D002675	Child, Preschool	A child between the ages of 2 and 5.	Children, Preschool,Preschool Child,Preschool Children
D004359	Drug Therapy, Combination	Therapy with two or more separate preparations given for a combined effect.	Combination Chemotherapy,Polychemotherapy,Chemotherapy, Combination,Combination Drug Therapy,Drug Polytherapy,Therapy, Combination Drug,Chemotherapies, Combination,Combination Chemotherapies,Combination Drug Therapies,Drug Polytherapies,Drug Therapies, Combination,Polychemotherapies,Polytherapies, Drug,Polytherapy, Drug,Therapies, Combination Drug
D005260	Female		Females
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man