Casal J Antonio, Mera Antonio, Pérez Luis F, Tutor J Carlos
Laboratorio Central, Hospital Clínico Universitario, Santiago de Compostela, Spain.
Clin Biochem. 2002 Sep;35(6):483-8. doi: 10.1016/s0009-9120(02)00339-9.
Recently it has been suggested that serum beta-N-acetylhexosaminidase (Hex) could be a joint destruction marker in rheumatoid arthritis (RA) patients. However, a large amount of serum Hex activity has its source from platelets, and the blood platelet-count is often increased in RA, which may have masked the significance of the results. The purpose of this study was to investigate the relationship between plasma activity of Hex and disease activity or severity.
In 51 patients with RA, with an evolution period for the illness of 10.9 +/- 1.2 yr (range 1-40 yr), we determined the total Hex activity together with its Hex A and B isoenzymes in plasma and in mononuclear (MN) and polymorphonuclear (PMN) leukocytes.
The plasma activity of total Hex and Hex B isoenzyme was slightly higher in the group of patients studied (p < 0.01), together with the specific activity of total Hex, Hex A and B in PMN leukocytes (p < 0.001) than in the control group. No significant correlation was found between plasma or leukocyte Hex and the radiologic evaluation of the disease (Sharp's modified method), or the patient's functional capacity (modified Health Assessment Questionnaire). Likewise, a significant correlation between Hex activity and laboratory inflammation markers (C reactive protein, sialic acid, erythrocyte sedimentation rate) or the evolution time of the disease was not found.
The plasma activity of total Hex, or even of its isoenzymes Hex A and Hex B, does not appear to be a reliable marker of erosion and cartilage degradation in RA patients. Liver function appears to be the major determinant for the plasma Hex activity in these patients.
最近有人提出，血清β-N-乙酰己糖胺酶（Hex）可能是类风湿关节炎（RA）患者关节破坏的标志物。然而，大量血清Hex活性来源于血小板，且RA患者血小板计数常升高，这可能掩盖了结果的意义。本研究的目的是探讨血浆Hex活性与疾病活动度或严重程度之间的关系。
对51例RA患者进行研究，其病程为10.9±1.2年（范围1 - 40年），我们测定了血浆以及单核（MN）和多形核（PMN）白细胞中的总Hex活性及其Hex A和B同工酶活性。
与对照组相比，所研究患者组的血浆总Hex和Hex B同工酶活性略高（p < 0.01），PMN白细胞中总Hex、Hex A和Hex B的比活性也更高（p < 0.001）。未发现血浆或白细胞Hex与疾病的放射学评估（夏普改良法）或患者的功能能力（改良健康评估问卷）之间存在显著相关性。同样，未发现Hex活性与实验室炎症标志物（C反应蛋白、唾液酸、红细胞沉降率）或疾病病程之间存在显著相关性。
血浆总Hex活性，甚至其同工酶Hex A和Hex B的活性，似乎都不是RA患者侵蚀和软骨降解的可靠标志物。肝功能似乎是这些患者血浆Hex活性的主要决定因素。
