Hughes K J, Rendle D I, Higgins S, Barron R, Cowling A, Love S, Durham A E
Weipers Centre for Equine Welfare, School of Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, UK.
The Liphook Equine Hospital, Hampshire, UK.
Equine Vet J. 2017 Mar;49(2):232-237. doi: 10.1111/evj.12587. Epub 2016 Jun 9.
Delays between collection and laboratory analysis of equine body fluid samples are common in practice; however, the effects of delays on the accuracy of results and diagnostic interpretation are unknown.
To assess the effects of storage time and temperature combination on protein and cell parameters of equine synovial and mesothelial cavity fluids and determine whether any changes affect clinicopathological interpretation.
In vitro experiment.
Body fluid samples obtained from horses during diagnostic investigation were divided into 7 aliquots and total protein concentration (TP), total nucleated cell count (TNCC) and neutrophil morphology were analysed immediately (T ) and at 24 (T ), 48 (T ) and 72 h (T ) after storage at 4 or 22°C. Linear mixed models were used to analyse effects of fluid type and storage conditions on TP, TNCC and neutrophil morphology grade. Changes in interpretation of samples over time and diagnostic performance at each analysis point were recorded.
A total of 32 samples were collected from 23 horses. Storage had no effect on TP. Cell count was influenced by fluid type and was significantly reduced at T for storage at 4°C and T , T and T for 22°C (P<0.001). Neutrophil morphology grade was significantly greater at T , T and T than at T for both 4 and 22°C (P<0.001). For 9 samples, the diagnostic interpretation changed over time. Specificity and positive predictive value at each analysis point was 100%; however, sensitivity and negative predictive value decreased with greater storage duration and temperature.
Alterations in the TNCC and neutrophil morphology of body fluid samples occur when analysis is delayed, especially with higher storage temperatures, and may influence interpretation and clinical decision-making. Body fluid samples should be analysed as soon as possible after collection to minimise preanalytical errors due to storage.
在实际操作中，马体液样本采集与实验室分析之间的延迟很常见；然而，延迟对结果准确性和诊断解读的影响尚不清楚。
评估储存时间和温度组合对马滑液和间皮腔液蛋白质和细胞参数的影响，并确定是否有任何变化会影响临床病理解读。
体外实验。
在诊断调查期间从马身上获取的体液样本分成7份，立即（T）以及在4℃或22℃储存24小时（T）、48小时（T）和72小时（T）后分析总蛋白浓度（TP）、总核细胞计数（TNCC）和中性粒细胞形态。采用线性混合模型分析液体类型和储存条件对TP、TNCC和中性粒细胞形态分级的影响。记录样本随时间的解读变化以及每个分析点的诊断性能。
共从23匹马身上采集了32个样本。储存对TP没有影响。细胞计数受液体类型影响，在4℃储存时T显著降低，在22℃储存时T、T和T显著降低（P<0.001）。对于4℃和22℃，中性粒细胞形态分级在T、T和T时均显著高于T（P<0.001）。9个样本的诊断解读随时间发生了变化。每个分析点的特异性和阳性预测值均为100%；然而，敏感性和阴性预测值随着储存时间和温度的增加而降低。
当分析延迟时，体液样本的TNCC和中性粒细胞形态会发生改变，尤其是在储存温度较高时，这可能会影响解读和临床决策。体液样本采集后应尽快分析以尽量减少因储存导致的分析前误差。
