Background Hemophilia A (HA) is an inherited bleeding disorder caused by a deficiency or defect in factor VIII (FVIII).

Methods We investigated the role of clot waveform analysis (CWA) of activated partial thromboplastin time in the diagnosis and therapeutic monitoring of HA. The changes in CWA parameters the maximum clotting velocity (|Min1|), maximum clotting acceleration (|Min2|), and maximum clotting deceleration (|Max2|) were detected among mild, moderate, and severe HA groups.

Results As the severity of HA subtypes increased, the levels of |Min1|, |Min2|, and |Max2| progressively decreased (p < 0.05). Receiver operating characteristic curve analysis showed that |Max2| and |Min2| were more effective than |Min1| in distinguishing different types of HA patients, with higher diagnostic efficacy. The standard curves based on Actin FSL reagent for normal and low levels of FVIII:C-|Max2| were established, with R2 values of 0.98 and 0.99, respectively. These curves can be utilized for monitoring during replacement therapies involving full-length recombinant FVIII and B-domain-deleted FVIII. Thirty cases of HA patients utilized the FVIII-|Max2| standard curve to obtain individual pharmacokinetics characteristic parameters. The clearance, half-life (t_1/2), time to FVIII:C of 1% above baseline (tt1%), and predicted dosage showed no statistically significant differences compared with one-stage assay (p > 0.05).

Conclusion CWA is an economical and practical tool, and its related parameters are associated with the severity of HA. It has promising clinical prospects in predicting FVIII:C levels and individualized treatment when HA patients undergo replacement therapy.

背景 A 型血友病 (HA) 是一种由 VIII 因子 (FVIII) 缺乏或缺陷引起的遗传性出血性疾病。

方法 我们研究了活化部分凝血活酶时间的血块波形分析 (CWA) 在 HA 诊断和治疗监测中的作用。检测轻度、中度和重度 HA 组中 CWA 参数的变化，即最大凝血速度 (|Min1|)、最大凝血加速度 (|Min2|) 和最大凝血减速度 (|Max2|)。

结果 随着 HA 亚型严重程度的增加，|Min1|、|Min2| 和 |Max2| 的水平升高。逐渐下降（p  <0.05）。接受者操作特征曲线分析表明|Max2|和 |Min2|比 |Min1| 更有效能够区分不同类型的HA患者，具有较高的诊断效能。基于肌动蛋白 FSL 试剂的正常和低水平 FVIII:C-|Max2| 的标准曲线建立了 R2 值分别为 0.98 和 0.99。这些曲线可用于在涉及全长重组 FVIII 和 B 结构域缺失的 FVIII 的替代疗法期间进行监测。 30 例 HA 患者使用 FVIII-|Max2|标准曲线以获得个体药代动力学特征参数。与一阶段测定相比，清除率、半衰期 (t _{1/2 )、FVIII:C 达到基线以上 1% 的时间 (tt1%) 和预测剂量没有统计学显着差异 (} p  > 0.05)。

结论 CWA是一种经济实用的工具，其相关参数与HA的严重程度相关。它在预测FVIII:C水平以及HA患者接受替代治疗时的个体化治疗方面具有广阔的临床前景。