D. Unsihuay, J. Reust, K. Bolte, I. Poventud-Fuentes, K. Patel
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引用次数: 0
Abstract
Background
Traditionally, urine analysis of calcium (Ca), magnesium (Mg) and phosphate (Phos) requires acidification of the sample. This study aims to assess the need for acidification and evaluate preanalytical factors that influence the accurate measurement of these analytes in urine.
Results
A total of 107 spot urine samples from patients with a median age of 9 years (95% ≤ 21 years of age, range 5 days to 46 years) were analyzed for Ca (n = 94), Mg (n = 97), and Phos (n = 102) with and without acidification. Analyses without acidification resulted in 27 outliers for Ca, 6 for Mg, and 17 for Phos that exceed the acceptability limits: 4% or ± 0.5 mg/dL for Ca, 12.5% or ± 0.1 mg/dL for Mg, and 5% or ± 0.15 mg/dL for Phos. Sample turbidity was found to be a contributing factor to these outliers. In a subset of 37 samples, centrifugation improved the correlation between acidified and unacidified samples (R2 > 0.99) for Ca (n = 35), Mg (n = 35), and Phos (n = 37). Only 3 outliers were found for Ca, 0 for Mg and 1 for Phos. The recovery of Ca in urine containing calcium oxalate (CaOx) (n = 5) was not affected by the addition of a centrifugation step in the sample pretreatment.
Significance
Our results suggest that urine acidification is not necessary for the analysis of Ca, Mg and Phos, but that centrifugation should be performed to overcome any turbidity interference.
期刊介绍：
The Official Journal of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC)
Clinica Chimica Acta is a high-quality journal which publishes original Research Communications in the field of clinical chemistry and laboratory medicine, defined as the diagnostic application of chemistry, biochemistry, immunochemistry, biochemical aspects of hematology, toxicology, and molecular biology to the study of human disease in body fluids and cells.
The objective of the journal is to publish novel information leading to a better understanding of biological mechanisms of human diseases, their prevention, diagnosis, and patient management. Reports of an applied clinical character are also welcome. Papers concerned with normal metabolic processes or with constituents of normal cells or body fluids, such as reports of experimental or clinical studies in animals, are only considered when they are clearly and directly relevant to human disease. Evaluation of commercial products have a low priority for publication, unless they are novel or represent a technological breakthrough. Studies dealing with effects of drugs and natural products and studies dealing with the redox status in various diseases are not within the journal''s scope. Development and evaluation of novel analytical methodologies where applicable to diagnostic clinical chemistry and laboratory medicine, including point-of-care testing, and topics on laboratory management and informatics will also be considered. Studies focused on emerging diagnostic technologies and (big) data analysis procedures including digitalization, mobile Health, and artificial Intelligence applied to Laboratory Medicine are also of interest.
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