A rapid LC-MS/MS method for determination of urinary EtG and application to a cut-off limit study

Ethyl glucuronide (EtG) is a metabolite and a specific marker of alcohol consumption that can be detected days after the complete elimination of alcohol after drinking. A rapid, simple, and sensitive LC-ESI-MS/MS method for the determination of urinary ethyl glucuronide was developed and fully validated in accordance with analytical standards, using the C-18 column. The whole process including sample preparation and LC-MS/MS lasted 10 min. A comprehensive validation including HorRat, measurement uncertainty, system suitability and intermediate precision calculations among analysts, and a cut-off limit study was performed. The method was applied to real samples and a cutoff limit determination study. The LOD and LOQ (using the IUPAC and Eurachem methods) were determined as 104.21 ng mL(-1) and 165.00 ng mL(-1). A cut-off limit of approximate to 818 ng mg(-1) (normalised to creatinine) was found for urinary EtG. The results showed that the cut-off limits currently in use should be re-considered in further studies and standardised on a global scale. Normalisation to creatinine is important because of the risk of the dilution of urine intentionally or with a change of diet. The concentrations of real samples from subjects who had consumed alcohol were successfully predicted using this method, after zero HS-GC/MS results of urine alcohol concentration. (C) 2015 Institute of Chemistry, Slovak Academy of Science

Does the ACR TI-RADS scoring allow us to safely avoid unnecessary thyroid biopsy? single center analysis in a large cohort

The American College of Radiology (ACR) has recently proposed a guideline that recommends clinicians to perform thyroid fine-needle aspiration biopsy (FNAB) on the basis of ultrasound features. In this study, we focused on nodules for which no biopsy is recommended by the ACR Thyroid Imaging, Reporting and Data System (TI-RADS) guideline