Project Details

A novel method for measuring zinc status in Indian children using nail clippings

Yvonne Goh, PhD

Summary

BACKGROUND: Zinc deficiency remains one of the most prevalent micronutrient deficiencies in children globally and is associated with reduced linear growth, impaired immune function, and increased diarrheal morbidity and mortality. GAP: Though plasma/serum zinc concentrations (PZC) is the recommended biomarker for assessment of zinc status at the population level, it is extremely challenging to measure in low resource settings. Nail zinc concentration, measured using the novel and portable X-ray fluorescence technique (XRF), is an emerging biomarker that is potentially more field-friendly and cost-effective to assess. The current study will assess the association between 1) nail zinc concentrations analyzed via XRF, and PZC analyzed via ICP-MS and 2) nail zinc concentrations analyzed via XRF vs ICP-MS. HYPOTHESIS: 1) There will be a moderate, positive correlation between nail zinc concentrations analyzed via XRF vs. plasma PZC analyzed via ICP-MS. 2) There will be a strong, positive correlation between nail zinc concentrations analyzed via XRF vs. nail zinc concentrations analyzed via ICP-MS. METHODS: This cross-sectional study will involve a sub-sample (n=70) of children 12-59 months enrolled in the Multiply-Fortified Salt (MFS) Study in Punjab, India. Fingernail and blood samples collected at baseline or endline will be analyzed for zinc using XRF and/or ICP-MS, as appropriate. The association between nail zinc measured with XRF vs. PZC and nail zinc measured via ICP-MS will be investigated using correlational analysis and Bland Altman plots. RESULTS: Pending. IMPACT: If the analysis of nail zinc with XRF correlates well with PZC and/or nail zinc with ICP-MS, this method may become a more field-friendly, non-invasive, and more affordable alternative to assess zinc status in children.