Abhijeet A Rakshasbhuvankar1,2,3, Michael W Clarke4,5, Karen Simmer6,7, Sanjay K Patole6,7, J Jane Pillow7,8. 1. Neonatal Clinical Care Unit, King Edward Memorial and Perth Children's Hospitals, Perth, Washington, Australia, abhijeet.rakshasbhuvankar@health.wa.gov.au. 2. The UWA Centre for Child Health Research, Telethon Kids Institute, Perth, Washington, Australia, abhijeet.rakshasbhuvankar@health.wa.gov.au. 3. School of Human Sciences, University of Western Australia, Perth, Washington, Australia, abhijeet.rakshasbhuvankar@health.wa.gov.au. 4. Metabolomics Australia, Centre for Microscopy, Characterisation, and Analysis, The University of Western Australia, Perth, Washington, Australia. 5. School of Biomedical Sciences, Faculty of Health and Medical Sciences, The University of Western Australia, Perth, Washington, Australia. 6. Neonatal Clinical Care Unit, King Edward Memorial and Perth Children's Hospitals, Perth, Washington, Australia. 7. The UWA Centre for Child Health Research, Telethon Kids Institute, Perth, Washington, Australia. 8. School of Human Sciences, University of Western Australia, Perth, Washington, Australia.
Abstract
BACKGROUND: Salivary measurement of hormones and vitamins is gaining prominence as a minimally invasive procedure with the negligible potential for harm. We aimed to assess the utility of saliva for assessing vitamin A status in extremely preterm infants. METHODS: Paired saliva and blood samples were collected at 4 weeks of age from infants born <28 weeks of gestation using a proprietary polymer swab. Plasma retinol was measured using high-performance liquid chromatography, and salivary retinol was measured using enzyme-linked immunosorbent assay. RESULTS: Thirty infants were recruited with a median (IQR) gestation and birth weight of 26.2 weeks (24.8-27.2) and 865 g (718-1,002), respectively. An adequate volume of saliva (>50 µL) was obtained in 68%. There was no significant correlation (Spearman's correlation coefficient = 0.16, p = 0.3) between individual plasma and salivary retinol levels. Bland-Altman analysis showed wide limits of agreement (-113 to +119%) between individual plasma and salivary retinol levels. CONCLUSION: Individual vitamin A status cannot be determined reliably from saliva in extremely preterm infants using current collection materials and analysis techniques.
BACKGROUND: Salivary measurement of hormones and vitamins is gaining prominence as a minimally invasive procedure with the negligible potential for harm. We aimed to assess the utility of saliva for assessing vitamin A status in extremely preterm infants. METHODS: Paired saliva and blood samples were collected at 4 weeks of age from infants born <28 weeks of gestation using a proprietary polymer swab. Plasma retinol was measured using high-performance liquid chromatography, and salivary retinol was measured using enzyme-linked immunosorbent assay. RESULTS: Thirty infants were recruited with a median (IQR) gestation and birth weight of 26.2 weeks (24.8-27.2) and 865 g (718-1,002), respectively. An adequate volume of saliva (>50 µL) was obtained in 68%. There was no significant correlation (Spearman's correlation coefficient = 0.16, p = 0.3) between individual plasma and salivary retinol levels. Bland-Altman analysis showed wide limits of agreement (-113 to +119%) between individual plasma and salivary retinol levels. CONCLUSION: Individual vitamin A status cannot be determined reliably from saliva in extremely preterm infants using current collection materials and analysis techniques.