Evaluation of 25-hydroxy vitamin D assay on the immunodiagnostic systems iSYS analyser.

Background: We evaluated the recently released chemiluminescence assay for 25-hydroxy vitamin D (25-OHD) on the Immunodiagnostic Systems iSYS (IDS-iSYS) automated analyser.

Methods: The IDS-iSYS comparison was performed using patient samples previously measured for 25-OHD by a validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method (n = 119) and an IDS enzyme immunoassy (IDS-EIA) method (n = 64). Limit of detection and limit of quantification were determined from a precision profile.

The correlation between third-trimester maternal and newborn-serum 25-hydroxy-vitamin D in a selected South Australian group of newborn samples.

Background: Although vitamin D insufficiency is prevalent in the community, only a few population-based studies have measured serum 25-hydroxy-vitamin D (25OHD) levels during pregnancy and in newborns. Maternal vitamin D deficiency has been linked to pregnancy complications, as well as hypocalcaemia and rickets in the newborn. Here, the authors report third-trimester maternal and newborn-serum 25OHD concentrations in 101 neonates whose serum samples were sent for testing.