Tuchman M, Yudkoff M
Department of Pediatrics and Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, Minnesota, 55455, USA.
Mol Genet Metab. 1999 Jan;66(1):10-5. doi: 10.1006/mgme.1998.2783.
Plasma levels of glutamine (456 determinations), alanine (434 determinations), and asparagine (431 determinations) and corresponding ammonia levels (260 determinations) were retrospectively analyzed in 30 patients with hyperammonemia secondary to urea cycle disorders (including 3 patients with amino acid transport defects) and 5 patients with propionic acidemia (PA). All patients had elevated glutamine levels on one or more testing except for 2 patients with severe PA and 1 patient with a mild urea cycle disorder. All but 4 patients with urea cycle disorders showed a maximal glutamine level higher than 100 micromol/dl, and 3 patients had a maximal glutamine level of higher than 200 micromol/dl. The only exceptions were 2 asymptomatic ornithine transcarbamylase (OTC)-deficient females, 1 male with mild OTC deficiency, and 1 patient with citrullinemia (CIT) whose plasma glutamine levels were never above 100 micromol/L. Patients with CIT and argininosuccinic aciduria (ASA) showed statistically significant lower levels of glutamine than patients with other urea cycle disorders. However, the maximal glutamine level did not directly correlate with severity of the disorder and within disorders correlated inversely with severity of outcome. Patients with PA showed statistically significant lower glutamine, alanine, and asparagine levels than patients with urea cycle disorders and the severity of this disorder correlated inversely with plasma glutamine levels. Plasma ammonia levels showed a positive correlation with glutamine in patients with carbamyl phosphate synthetase I and OTC deficiency and a negative correlation in patients with PA. Although, most patients also showed elevated levels of alanine and asparagine, their levels generally did not show a good correlation with glutamine (R2 = 0.25 and 0.34, respectively).
对30例继发于尿素循环障碍的高氨血症患者（包括3例氨基酸转运缺陷患者）和5例丙酸血症（PA）患者的血浆谷氨酰胺水平（456次测定）、丙氨酸水平（434次测定）、天冬酰胺水平（431次测定）及相应的氨水平（260次测定）进行了回顾性分析。除2例严重PA患者和1例轻度尿素循环障碍患者外，所有患者在一次或多次检测中谷氨酰胺水平均升高。除4例尿素循环障碍患者外，其余患者的谷氨酰胺最高水平均高于100 μmol/dl，3例患者的谷氨酰胺最高水平高于200 μmol/dl。仅有的例外是2例无症状的鸟氨酸转氨甲酰酶（OTC）缺乏的女性、1例轻度OTC缺乏的男性和1例瓜氨酸血症（CIT）患者，其血浆谷氨酰胺水平从未高于100 μmol/L。CIT和精氨琥珀酸尿症（ASA）患者的谷氨酰胺水平在统计学上显著低于其他尿素循环障碍患者。然而，谷氨酰胺最高水平与疾病严重程度无直接相关性，且在不同疾病中与预后严重程度呈负相关。PA患者的谷氨酰胺、丙氨酸和天冬酰胺水平在统计学上显著低于尿素循环障碍患者，且该疾病的严重程度与血浆谷氨酰胺水平呈负相关。在氨基甲酰磷酸合成酶I和OTC缺乏的患者中，血浆氨水平与谷氨酰胺呈正相关，而在PA患者中呈负相关。虽然大多数患者的丙氨酸和天冬酰胺水平也升高，但其水平通常与谷氨酰胺无良好相关性（R2分别为0.25和0.34）。
