Department of Pediatrics, Division of Neonatology, University of Utah School of Medicine, Salt Lake City, Utah,
Department of Pediatrics, Division of Neonatology, University of Utah School of Medicine, Salt Lake City, Utah, USA.
Neonatology. 2019;115(1):5-12. doi: 10.1159/000491626. Epub 2018 Sep 5.
Schistocytes are circulating erythrocyte fragments. They can be identified microscopically from a blood smear; but automated systems evaluate more cells and avoid inconsistencies in microscopy. Studies using adult subjects indicate that automated quantification of schistocytes can be clinically useful. However, reference intervals for automated schistocyte counts of neonates have not been published, and the relevance of a high automated schistocyte count from neonates has not been reported.
Using retrospective automated neonatal complete blood count (CBC) data, we created reference intervals for fragmented red cells (FRCs) and sought to discover the clinical conditions of neonates with high FRCs (above the upper reference interval).
We created reference intervals based on 39,949 CBCs from 15,655 neonates 0-90 days old. The lower reference interval was 0 FRC/µL and the upper interval was 100,000/µL. The highest FRCs (96 CBCs from 44 neonates) were > 250,000/µL. These neonates clustered into the following groups: 37% had sepsis, 29% had disseminated intravascular coagulation (DIC), 17% had a genetic syndrome, 14% necrotizing enterocolitis (NEC), and 7% had iron deficiency (some had more than one diagnosis). Based on the reference intervals, we divided the 39,949 FRC values into 3 groups: (1) < 100,000/µL ("normal"), (2) 100,000-200,000/µL ("moderately elevated"), and (3) > 200,000/µL ("extremely elevated"). The odds that a microangiopathic condition (DIC, sepsis, NEC) or a microcytic disorder (iron deficiency) were present were significantly higher in the moderately elevated, and more so in the extremely elevated group.
Our study suggests that a high FRC could prompt investigation into, or inform follow-up of, a neonatal microangiopathic or extremely microcytic disorder.
裂片红细胞是循环红细胞碎片。可以通过血涂片显微镜下识别；但自动化系统可以评估更多的细胞，并避免显微镜检查的不一致性。使用成人受试者的研究表明，自动化定量检测裂片红细胞可能具有临床意义。然而，尚未公布新生儿自动裂片红细胞计数的参考区间，也尚未报道新生儿高自动裂片红细胞计数的相关性。
使用回顾性自动新生儿全血细胞计数（CBC）数据，我们为破碎红细胞（FRC）创建了参考区间，并试图发现 FRC 较高（高于上参考区间）的新生儿的临床情况。
我们基于 15655 名 0-90 天新生儿的 39949 份 CBC 数据创建了参考区间。下参考区间为 0 FRC/µL，上参考区间为 100000/µL。最高的 FRC（来自 44 名新生儿的 96 个 CBC）>250000/µL。这些新生儿分为以下几组：37%有败血症，29%有弥漫性血管内凝血（DIC），17%有遗传综合征，14%有坏死性小肠结肠炎（NEC），7%有缺铁（有些有多种诊断）。基于参考区间，我们将 39949 个 FRC 值分为 3 组：（1）<100000/µL（“正常”），（2）100000-200000/µL（“中度升高”），和（3）>200000/µL（“极度升高”）。中度升高和更严重升高组中，微血管病（DIC、败血症、NEC）或小细胞性疾病（缺铁）存在的可能性显著更高。
我们的研究表明，高 FRC 可能提示新生儿微血管病或极度小细胞性疾病的检查或随访。
