Infants biotin

The physiologic sequelae of biotin deficiency are almost unexplored. Severe skin lesions, especially seborrheic dermatitis and Leiner s disease (Erythroderma desquamativum or exfoliative dermatitis), were increased in young infants bom of mothers on a restricted diet low in eggs, livers, and other biotin-rich foods. After biotin administration the lesions healed. There are claims that excess biotin produces a fatty liver characterized by heightened cholesterol content. Choline has no effect in the prevention of biotin-fatty livers (G2, M2). In mice with transplanted tumors, both the tumors and the blood levels of biotin are below normal (R8). More recent studies established a protection with avidin, the biotin-binding fraction of egg white, against tumor formation (K4). More data along these lines are still needed for confirmation. 

INDYK HE et al. (2000), Determination of biotin and folate in infant formula and milk by optical biosensor-based immunoassay , JAOCS, 83(5), 1141-8. 

Determination of biotin in cereals, multivitamin tablet, fruit juice, infant milk, yogurt, meat, and vegetables... 

Biotin (68) is an essential growth factor for many microorganisms, but biotin deficiency is not normally found in man, except perhaps in infants. Its only therapeutic use is in the treatment of seborrhoeic dermatitis of infancy, but it has been tried for the treatment of some forms of baldness. Another heterocyclic sulfur compound, lipoic acid (69), serves as a prosthetic group in several enzymes but it has not been associated with any deficiency disease and has no therapeutic use. 

Biotin 0.15-0.3 mg/day. The discovery that biotin deficiency in young chickens can lead to sudden death resulted in a recommendation to supplement infant formulations with biotin.3 Desthiobiotin, in which the sulfur has been removed and replaced by two hydrogen atoms, can replace biotin in some organisms and appears to lie on one pathway of biosynthesis. b/C Oxybiotin, in which the sulfur has been replaced by oxygen, is active for many organisms and partially active for others. No evidence for conversion to biotin itself has been reported, and oxybiotin may function satisfactorily in at least some enzymes. 

The literature contains very little on methods for biotin determination in foods. Microbiological assays of biotin predominate in food work (19,180). Table 23 summarizes a recent HPLC method for the analysis of biotin in infant formula. 

Biotin and biotin analogs Infant formula Protein precipitation using concentrated hydrochloric acid neutralization with 6 M NaOH lipid extraction with n-hexane Precolumn Microsorb C18 (15 X 4.6 mm, 5 jam Rainin). Analytical Microsorb C18 (250 X 4.6 mm, 5 /zm Rainin). Isocratic 100 mM phosphate buffer, pH 7.0 + methanol (80 + 20, v/v). 0.4 ml/min. Postcolumn reaction system UV absorbance at 220 nm followed by streptavidin-fluorescein isothiocyanate (2.0 mg/L) knitted open tubular reaction system (10.0 m x 0.5-mm ID) at a flow rate External standardization. 184 Linear range = 0.08-1.00 fjM biotin. LoD = 0.02 /zM or 97 pg biotin at SNR = 3. Repeatability CV 3.5% for biotin in infant formula. 

Children with biotinidase deficiency are usually treated with 5-10 mg of oral biotin. We often use the same dose for infants as we do for older children. This obviously means that the dose of biotin per body weight is decreasing as the child gets older. How might one determine if the dose of biotin is adequate or if higher doses are necessary ... 

The bioassay was used to determine the bioavailability of zinc in milk-base and soy-base infant formulas (7). The results are shown in Figure 2 and Table 1. The low zinc basal diet contained (%) spray dried egg white powder, 20 com oil, 10 non-nutritive fibre, 3 starch, 25 biotin, 0.0004 vitamin mixture, 1 salt mixture, excluding zinc, 4 dextrose, 37. 

The affected infants have a normal plasma concentration of biotin and excrete normal amounts of biotin in the urine. Skin fibroblasts have extremely low activities of aU four biotin-dependent carboxylases when they are cultured in media containing approximately physiological concentrations of biotin. But, culture with considerably higher concentrations of biotin results in normal activity of aU four carboxylases. The defect is in the affinity of holocarboxylase synthetase for biotin (its is 20- to 70-fold higher than normal). 

The problem is a functional deficiency of biotin, due both to inability to release free biotin from dietary biocytin and also to failure of the normal recovery of free biotin by biotinidase action on the biocytin released by proteolysis of biotin-containing enzymes. Normal intakes of biotin are inadequate to meet the requirements of these patients the provision of pharmacological doses of free biotin provides an adequate amount to meet requirements without the need for reutUization. The delayed development of clinical and biocheimcal abnormalities is a result of the accumulation of biotin by the fetus, so that at birth the infant has adequate stores of the vitamin. 

Cot Death Cot death, or Sudden Infant Death Syndrome, when an apparently healthy child dies suddenly, and from no apparent cause, has some similarities with the fatty liver and kidney syndrome in birds. It has been suggested that it may result from marginal biotin deficiency, together with a precipitating metabolic stress. 

There is circumstantial evidence to support this suggestion, because the liver content of biotin is lower in infants who have died from cot death than in infants who have died from known causes. By parallel with the fatty liver and kidney syndrome, it has been suggested that a modest metabolic stress, such as a mild fever, causes a higher requirement for gluconeogenesis than can be met, resulting in acute hypoglycemia. There are rapid postmortem changes in... 

Heard GS, Hood RL, and Johnson AR (1983) Hepatic biotin and the sudden infant death syndrome. Medical Journal of Australia 2, 305-6. 

Vitamin D is partly produced by the skin on exposure to sunlight vitamin K and biotin are produced in part by intestinal bacteria and vitamin B12 is especially well-stored. Hence, it is uncommon to have a deficiency of these vitamins on the basis of dietary intake alone. Infants, who have less bacterial intestinal flora and relatively little stores of vitamin K have a greater need than adults for vitamin K in the diet. 

Biotinidase deficiency is an autosomal recessive disorder with an estimated incidence of 1 in 72,000-126,0(X). Many newborn-screening programs of genetic diseases include testing for this enzyme. Prompt treatment with oral biotin administration of 5-20 mg/d in affected infants will prevent clinical consequences. If the treatment is delayed, neurological manifestations (e.g., hearing loss and optic atrophy) and developmental delay occur and may not revert to normal. 

The normal recommended intake for biotin is age-dependent Infants require 10-20 pg/day, children 25-30 pg/day and adolescents and adults 30-100 pg/day. Biotin deficiency is rare, but can lead to seborrhoea (excessive secretion of sebmn from the sebaceous glands in the skin), dermatitis, loss of appetite, muscular pain, lethargy, and nervous disturbances (Tab. 7.3). [109]... 

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