Serum biotin in Japanese children: Enzyme-linked immunosorbent assay measurement

Association between Serum Biotin Levels and Cedar Pollinosis in Japanese Schoolchildren

Biotin is a water-soluble B complex vitamin and coenzyme of five types of carboxylase and plays crucial roles in fatty acid, glucose, and amino acid metabolism. Nutritional biotin deficiency and defective enzymes essential for biotin metabolism cause inflammatory diseases such as eczema-like dermatitis and Crohn's disease; however, little is known about the pathophysiological roles of biotin. This study investigated the relationship between biotin metabolism and human allergic sensitization and diseases by measuring serum levels of biotin, total immunoglobulin E (IgE) and allergen-specific IgEs in more than 400 Japanese schoolchildren aged 6 to 12. The prevalence of allergic diseases, and environmental and life-style factors were also examined by a questionnaire. Like total IgE, serum biotin levels of children showed a log-normal distribution. Meanwhile, Spearman's rank correlation analysis showed weak but significant positive associations between serum biotin levels and total IgE (rho=0.147, p=0.0029) as well as allergen-specific IgEs against egg whites (rho=0.215, p=0.00013), cedar pollen (rho=0.176, p=0.00036), and cat dander (rho=0.130, p=0.0085). Furthermore, mean serum biotin levels in children with cedar pollinosis, but not with other allergic diseases such as asthma and allergic rhinitis, were significantly higher than in those without (p=0.0015). These results suggest a correlation between serum biotin levels and the development of cedar pollinosis. Further prospective studies are needed to evaluate the causal relationship between biotin metabolism and cedar pollen sensitization and pollinosis development.

Quantification of biotin in plasma samples by column switching liquid chromatography - tandem mass spectrometry

Biotin (or Vitamin B7) is a vitamin where deficiency can be caused by inadequate intake. Biotin deficiency is rare, as most people get enough biotin from diet, since many foods contain biotin. In addition to biotin from food, intestinal bacteria can synthesize biotin, which can then be absorbed by the body. Supplementation with biotin has been advocated, mainly due to proposed beneficial effects on skin, nail and hair growth. There is no evidence that high biotin intakes are toxic, but a high intake may interfere with diagnostic assays that use biotin-streptavidin technology. These tests are commonly used to measure plasma concentrations of a wide range of hormones. Erroneous results may lead to misdiagnosis of various endocrine disorders. Supplementation with high-dose biotin has been used experimental for the treatment of diseases (e.g. multiple sclerosis) and high doses are used to obtain effect on nail and hair growth. On this background a demand for tests to determine if there is a risk of obtaining false test results when using biotin-streptavidin based tests have appeared. In this paper we present a method based on column switching liquid chromatography tandem mass spectrometry for the quantification of biotin in plasma and serum and explore the effects of biotin on an immunoassay based on biotin strept(avidin) chemistry.

Clinical risk assessment of biotin interference with a high-sensitivity cardiac troponin T assay

Objectives

Biotin >20.0 ng/mL (81.8 nmol/L) can reduce Elecsys® Troponin T Gen 5 (TnT Gen 5; Roche Diagnostics) assay recovery, potentially leading to false-negative results in patients with suspected acute myocardial infarction (AMI). We aimed to determine the prevalence of elevated biotin and AMI misclassification risk from biotin interference with the TnT Gen 5 assay.

Methods

Biotin was measured using an Elecsys assay in two cohorts: (i) 797 0-h and 646 3-h samples from 850 US emergency department patients with suspected acute coronary syndrome (ACS); (ii) 2023 random samples from a US laboratory network, in which biotin distributions were extrapolated for higher values using pharmacokinetic modeling. Biotin >20.0 ng/mL (81.8 nmol/L) prevalence and biotin 99th percentile values were calculated. AMI misclassification risk due to biotin interference with the TnT Gen 5 assay was modeled using different assay cutoffs and test timepoints.

Results

ACS cohort: 1/797 (0.13%) 0-h and 1/646 (0.15%) 3-h samples had biotin >20.0 ng/mL (81.8 nmol/L); 99th percentile biotin was 2.62 ng/mL (10.7 nmol/L; 0-h) and 2.38 ng/mL (9.74 nmol/L; 3-h). Using conservative assumptions, the likelihood of false-negative AMI prediction due to biotin interference was 0.026% (0-h result; 19 ng/L TnT Gen 5 assay cutoff). US laboratory cohort: 15/2023 (0.74%) samples had biotin >20.0 ng/mL (81.8 nmol/L); 99th percentile biotin was 16.6 ng/mL (68.0 nmol/L). Misclassification risk due to biotin interference (19 ng/L TnT Gen 5 assay cutoff) was 0.025% (0-h), 0.0064% (1-h), 0.00048% (3-h), and <0.00001% (6-h).

Conclusions

Biotin interference has minimal impact on the TnT Gen 5 assay’s clinical utility, and the likelihood of false-negative AMI prediction is extremely low.

Mimicking the human environment in mice reveals that inhibiting biotin biosynthesis is effective against antibiotic-resistant pathogens

To revitalize the antibiotic pipeline, it is critical to identify and validate new antimicrobial targets¹. In Mycobacteria tuberculosis and Francisella tularensis, biotin biosynthesis is a key fitness determinant during infection^2-5, making it a high-priority target. However, biotin biosynthesis has been overlooked for priority pathogens such as Acinetobacter baumannii, Klebsiella pneumoniae and Pseudomonas aeruginosa. This can be attributed to the lack of attenuation observed for biotin biosynthesis genes during transposon mutagenesis studies in mouse infection models^6-9. Previous studies did not consider the 40-fold higher concentration of biotin in mouse plasma compared to human plasma. Here, we leveraged the unique affinity of streptavidin to develop a mouse infection model with human levels of biotin. Our model suggests that biotin biosynthesis is essential during infection with A. baumannii, K. pneumoniae and P. aeruginosa. Encouragingly, we establish the capacity of our model to uncover in vivo activity for the biotin biosynthesis inhibitor MAC13772. Our model addresses the disconnect in biotin levels between humans and mice, and explains the failure of potent biotin biosynthesis inhibitors in standard mouse infection models.