Haysom Laura Z, Lee-Fowler Tekla M, Spangler Elizabeth A
Department of Clinical Sciences, College of Veterinary Medicine, Auburn University, Auburn, AL, USA.
Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL, USA.
Vet Clin Pathol. 2018 Sep;47(3):471-476. doi: 10.1111/vcp.12624. Epub 2018 Jun 27.
Storage and temperature significantly impact bronchoalveolar lavage fluid (BALF) analysis, and shipment of samples to diagnostic laboratories is often necessary. Alternative sample preparation methods could limit storage and temperature effects.
This study aimed to determine if airway wash samples that were fixed in formalin after being embedded in Histogel or Gelfoam gave comparable results to fresh cytocentrifuged or sediment smear preparations for the evaluation of cell morphology.
Eleven bronchoalveolar lavage and 3 transtracheal wash fluids were available, including 8 canine, 1 feline, and 5 equine samples. Cytocentrifuged and sediment smear preparations were prepared for routine analysis. Airway fluids were reserved for further evaluation. Total nucleated cell counts (TNCCs) were determined using a hemocytometer. The remaining fluid was used for Histogel and Gelfoam preparations. Each preparation was analyzed by a single board-certified clinical pathologist and assigned cellularity (1-3) and morphology scores (1-4).
Cellularity and morphology were significantly worse for the sediment smear, Histogel, and Gelfoam preparations compared with the cytocentrifuged preparations. The Gelfoam preparations had significantly worse cellularity scores than all other methods. Cellularity scores for sediment smears and Histogel preparations were significantly correlated with TNCCs.
TNCCs impacted the cellularity of the sediment smears and Histogel preparations. Cytocentrifuged preparations resulted in the best cellularity and morphology and are, therefore, recommended whenever possible. Neither the Histogel nor the Gelfoam methods demonstrated any advantage over sediment smear preparations, and both performed poorly when compared with cytocentrifuged preparations. Therefore, we do not recommend the use of these methods.
储存和温度对支气管肺泡灌洗液（BALF）分析有显著影响，通常需要将样本运送到诊断实验室。替代样本制备方法可能会限制储存和温度的影响。
本研究旨在确定在组织胶（Histogel）或明胶海绵（Gelfoam）中包埋后用福尔马林固定的气道冲洗样本，在评估细胞形态方面，其结果是否与新鲜的细胞离心涂片或沉淀涂片制备物相当。
共有11份支气管肺泡灌洗液和3份经气管冲洗液，包括8份犬类样本、1份猫类样本和5份马类样本。制备细胞离心涂片和沉淀涂片用于常规分析。保留气道冲洗液用于进一步评估。使用血细胞计数器测定总核细胞计数（TNCC）。将剩余的液体用于制备组织胶和明胶海绵样本。每份样本由一名获得委员会认证的临床病理学家进行分析，并给出细胞数量（1 - 3级）和形态学评分（1 - 4级）。
与细胞离心涂片相比，沉淀涂片、组织胶和明胶海绵样本的细胞数量和形态明显较差。明胶海绵样本的细胞数量评分明显低于所有其他方法。沉淀涂片和组织胶样本的细胞数量评分与总核细胞计数显著相关。
总核细胞计数影响沉淀涂片和组织胶样本的细胞数量。细胞离心涂片制备的样本细胞数量和形态最佳，因此尽可能推荐使用。组织胶和明胶海绵方法均未显示出优于沉淀涂片的优势，与细胞离心涂片相比表现均较差。因此，我们不建议使用这些方法。
