Análise da estabilidade pré-analítica do paratormônio canino submetido à centrifugação refrigerada, convencional e com resfriamento adaptado

Abstract

The measurement of parathyroid hormone (PTH) is challenging and can be significantly affected by pre-analytical factors. Refrigerated blood collection and centrifugation are recommended; however, access to specialized laboratory equipment is often limited. In this context, the present study aimed to evaluate the pre-analytical stability of canine PTH subjected to adapted cooled centrifugation (CTRes) and room-temperature centrifugation (CTA), in comparison with standard refrigerated centrifugation (CTRef). A total of 18 dogs were included, comprising nine animals in the control group (CG) and nine dogs with chronic kidney disease (GPTH) and suspected elevated PTH concentrations. Each dog underwent a single blood collection of 3 mL, which was equally aliquoted and processed using CTRef, CTRes (refrigerated centrifugation with frozen water tubes), and CTA. Plasma PTH (1–84) concentrations were determined using an immunoassay. Both CTRes and CTA demonstrated high agreement with CTRef in the quantification of PTH (1–84), with concordance rates of 98% and 96.1%, respectively, and minimal bias relative to CTRef when analyzed by a third-party laboratory. No significant differences were observed among the methods, indicating the feasibility of CTRes and CTA as alternative pre-analytical processing approaches. Therefore, sample processing using CTRes and CTA represents reliable alternatives to conventional refrigerated centrifugation (CTRef) for canine PTH measurement, particularly in resource- limited settings, supporting the diagnosis of mineral metabolism disorders, provided that blood samples are collected and transported under refrigerated conditions.