Lartigau-Roussin C, Paclet M H, Audin H, Toussaint B, Henni T, Raffray L
Service de gastro-entérologie et de médecine interne, centre hospitalier Gabriel-Martin, 38, rue Labourdonnais, 97460 Saint-Paul, Réunion.
Laboratoire de biochimie des enzymes et des protéines, DBTP, institut de biologie et pathologie, CHU Grenoble Alpes, 38043 Grenoble, France.
Rev Med Interne. 2017 Mar;38(3):210-213. doi: 10.1016/j.revmed.2016.05.015. Epub 2016 Oct 13.
Macro-AST is recognized as a classical aetiology of isolated and persistent increase of serum aspartate aminotransferase (AST) levels. Macro-AST are high molecular weight complexes associating AST and a macromolecule, often an immunoglobulin. Although those macroenzymes of unknown pathogenesis are usually non-pathogenic, association with several diseases, including autoimmune diseases and liver diseases has been described.
We report here the case of a 45-year-old patient with previously normal liver enzymes in whom an AST elevation and an IgA monoclonal gammopathy were discovered concomitantly. Following the diagnosis of multiple myeloma, we could evidence in the patient's serum a complex between AST and the monoclonal IgA. AST levels course followed closely the progression of monoclonal gammopathy.
This is the first report demonstrating a clear link between macro-AST and a monoclonal gammopathy.
巨AST被认为是血清天冬氨酸氨基转移酶（AST）水平单独持续升高的经典病因。巨AST是AST与大分子（通常是免疫球蛋白）结合形成的高分子量复合物。尽管这些发病机制不明的巨酶通常无致病性，但已有报道称其与多种疾病相关，包括自身免疫性疾病和肝脏疾病。
我们在此报告一例45岁患者，其既往肝酶正常，此次同时发现AST升高和IgA单克隆丙种球蛋白病。在诊断为多发性骨髓瘤后，我们在患者血清中证实了AST与单克隆IgA之间的复合物。AST水平变化与单克隆丙种球蛋白病的进展密切相关。
这是第一份证明巨AST与单克隆丙种球蛋白病之间存在明确联系的报告。
