Mudd S H, Levy H L, Tangerman A, Boujet C, Buist N, Davidson-Mundt A, Hudgins L, Oyanagi K, Nagao M, Wilson W G
Laboratory of General and Comparative Biochemistry, National Institute of Mental Health, Bethesda, MD 20892-4094, USA.
Am J Hum Genet. 1995 Oct;57(4):882-92.
New information has been obtained on 30 patients with isolated persistent hypermethioninemia, most of them previously unreported. Biopsies to confirm the presumptive diagnosis of partially deficient activity of ATP: L-methionine S-adenosyltransferase (MAT; E.C.2.5.1.6) in liver were not performed on most of these patients. However, none showed the clinical findings or the extreme elevations of serum folate previously described in other patients with isolated hypermethioninemia considered not to have hepatic MAT deficiency. Patients ascertained on biochemical grounds had no neurological abnormalities, and 27/30 had IQs or Bayley development-index scores within normal limits or were judged to have normal mental development. Methionine transamination metabolites accumulated abnormally only when plasma methionine concentrations exceeded 300-350 microM and did so more markedly after 0.9 years of age. Data were obtained on urinary organic acids as well as plasma creatinine concentrations. Patterns of inheritance of isolated hypermethioninemia were variable. Considerations as to the optimal management of this group of patients are discussed.
已获得30例孤立性持续性高蛋氨酸血症患者的新信息,其中大多数此前未报道过。多数患者未进行肝脏活检以证实三磷酸腺苷:L-蛋氨酸S-腺苷转移酶(MAT;E.C.2.5.1.6)活性部分缺乏的初步诊断。然而,这些患者均未出现先前在其他被认为无肝脏MAT缺乏的孤立性高蛋氨酸血症患者中描述的临床症状或血清叶酸极度升高的情况。基于生化指标确诊的患者无神经学异常,30例中有27例智商或贝利发育指数评分在正常范围内,或被判定精神发育正常。仅当血浆蛋氨酸浓度超过300 - 350微摩尔/升时,蛋氨酸转氨代谢产物才会异常蓄积,且在0.9岁后更为明显。获取了尿有机酸以及血浆肌酐浓度的数据。孤立性高蛋氨酸血症的遗传模式各不相同。本文讨论了关于这组患者最佳治疗方案的相关考虑因素。