1. Comparison of different preparation techniques of dried blood spot quality controls in newborn screening for congenital adrenal hyperplasia
- Author
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Nóra Grecsó, Ákos Baráth, Péter Monostori, Gábor Rácz, Zsolt Galla, Anita Zádori, and Csaba Bereczki
- Subjects
Congenital Adrenal Hyperplasia ,Physiology ,Systems Engineering ,Biochemistry ,Mass Spectrometry ,Cortisol ,Analytical Chemistry ,Medical Conditions ,Spectrum Analysis Techniques ,Filter Paper ,Liquid chromatography–mass spectrometry ,Tandem Mass Spectrometry ,Animal Cells ,Red Blood Cells ,Medicine and Health Sciences ,03.02. Klinikai orvostan ,Lipid Hormones ,Dried blood ,Liquid Chromatography ,Multidisciplinary ,Organic Compounds ,17-alpha-Hydroxyprogesterone ,Chromatographic Techniques ,Dried blood spot ,Body Fluids ,Laboratory Equipment ,Chemistry ,Blood ,Genetic Diseases ,Physical Sciences ,Medicine ,Engineering and Technology ,Steroids ,Anatomy ,Cellular Types ,Research Article ,Analyte ,Science ,Liquid Chromatography-Mass Spectrometry ,Cortodoxone ,Equipment ,Steroid biosynthesis ,Research and Analysis Methods ,Neonatal Screening ,Autosomal Recessive Diseases ,medicine ,Humans ,Congenital adrenal hyperplasia ,Clinical Genetics ,Reproducibility ,Newborn screening ,Steroid Hormones ,Chromatography ,Blood Cells ,Adrenal Hyperplasia, Congenital ,business.industry ,Organic Chemistry ,Androstenedione ,Infant, Newborn ,Chemical Compounds ,Biology and Life Sciences ,Cell Biology ,medicine.disease ,Hormones ,Dried Blood Spot Testing ,business ,Quality Assurance - Abstract
In newborn screening, samples suspected for congenital adrenal hyperplasia (CAH), a potentially lethal inborn error of steroid biosynthesis, need to be confirmed using liquid chromatography–tandem mass spectrometry. Daily quality controls (QCs) for the 2nd-tier CAH assay are not commercially available and are therefore generally prepared within the laboratory. For the first time, we aimed to compare five different QC preparation approaches used in routine diagnostics for CAH on the concentrations of cortisol, 21-deoxycortisol, 11-deoxycortisol, 4-androstenedione and 17-hydroxyprogesterone in dried blood spots. The techniques from Prep1 to Prep5 were tested at two analyte concentrations by spiking aliquots of a steroid-depleted blood, derived from washed erythrocyte suspension and steroid-depleted serum. The preparation processes differed in the sequence of the preparation steps and whether freeze-thaw cycles were used to facilitate blood homogeneity. The five types of dried blood spot QCs were assayed and quantitated in duplicate on five different days using a single calibration row per day. Inter-assay variations less than 15% and concentrations within ±15% of the nominal values were considered acceptable. Results obtained by means of the four dried blood spot QC preparation techniques (Prep1, Prep2, Prep4 and Prep5) were statistically similar and remained within the ±15% ranges in terms of both reproducibility and nominal values. However, concentration results for Prep3 (spiking prior to three freeze-thaw cycles) were significantly lower than the nominal values in this setting, with differences exceeding the ±15% range in many cases despite acceptable inter-assay variations. These findings have implications for the in-house preparation of QC samples in laboratory developed tests for CAH, including 2nd-tier assays in newborn screening.
- Published
- 2021