Department of Pathology and Laboratory Medicine, NorthShore University HealthSystem, Evanston, IL, USA.
Department of Pathology, University of Chicago Pritzker School of Medicine, Chicago, IL, USA.
Lab Med. 2022 Sep 1;53(5):479-482. doi: 10.1093/labmed/lmac026.
To evaluate the difference in lactate dehydrogenase (LDH) concentrations in plasma vs serum specimens in our patient population.
We measured LDH in 110 paired plasma and serum specimens over a 2-week period. Hemolytic indices were performed on each specimen. These paired specimens were drawn in a single setting and stored under the same conditions. For the last 14 paired specimens, cell counts were performed on the plasma/serum.
Plasma LDH was on average 22% higher than serum LDH. There was no difference in the hemolytic indices between the plasma and the serum specimens. In the last 14 specimens, cell counts revealed increased platelets in the plasma specimens compared to the serum specimens.
We propose switching back to using serum for LDH testing because there was unpredictable elevation in plasma LDH concentrations. These elevations in LDH levels may be linked to the platelets present in plasma and that may lyse or become activated with storage at refrigerated temperature.
评估本患者人群中血浆与血清标本中乳酸脱氢酶（LDH）浓度的差异。
我们在两周内测量了 110 对血浆和血清标本中的 LDH。对每个标本进行溶血指数检测。这些配对标本均在同一时间采集，并在相同条件下储存。对于最后 14 对配对标本，对血浆/血清进行细胞计数。
血浆 LDH 平均比血清 LDH 高 22%。血浆和血清标本之间的溶血指数无差异。在最后 14 个标本中，细胞计数显示血浆标本中的血小板数量高于血清标本。
我们建议改用血清进行 LDH 检测，因为血浆 LDH 浓度不可预测地升高。LDH 水平的这些升高可能与存在于血浆中的血小板有关，这些血小板可能在冷藏温度下储存时发生裂解或被激活。
