Mizock B A, Sabelli H C, Dubin A, Javaid J I, Poulos A, Rackow E C
Department of Medicine, Cook County Hospital, Chicago, IL 60612.
Arch Intern Med. 1990 Feb;150(2):443-9. doi: 10.1001/archinte.150.2.443.
We elected to test the hypothesis that the metabolic encephalopathy associated with systemic sepsis may have a pathogenesis that is similar to hepatic encepathology, ie, as the consequence of hepatic dysfunction that induces alterations in synthesis of catecholic and noncatecholic neurotransmitters. Eleven patients with septic encephalopathy were compared with nine patients with septic encephalopathy and nine normal controls with respect to blood and cerebrospinal fluid (CSF) amino acid profile, phenylethylamine and its metabolite phenylacetic acid, and blood ammonia. Blood and CSF levels of phenylacetic acid increased markedly in septic and hepatic encephalopathy while CSF phenylethylamine levels were not increased in either condition, presumably due to rapid turnover. The CSF concentrations of all the aromatic amino acids were increased in hepatic encephalopathy, whereas in the patients with sepsis, only phenylalanine levels were increased. Evidence of stimulated neutral amino acid transport into brain was demonstrated in hepatic not septic encephalopathy and appeared to correlate with the CSF glutamine concentration. Blood ammonia levels were increased in hepatic but not in septic encephalopathy. Our data support the hypothesis that metabolites of phenylethylamine contribute to encephalopathy in systemic sepsis and hepatic failure; however, the entities differ in other respects.
与全身性脓毒症相关的代谢性脑病可能具有与肝性脑病相似的发病机制，即作为肝功能障碍的结果，其可诱导儿茶酚胺和非儿茶酚胺神经递质合成的改变。我们比较了11例脓毒症脑病患者、9例脓毒症脑病患者以及9名正常对照者的血液和脑脊液（CSF）氨基酸谱、苯乙胺及其代谢产物苯乙酸以及血氨水平。在脓毒症和肝性脑病中，血液和脑脊液中的苯乙酸水平均显著升高，而在这两种情况下脑脊液中的苯乙胺水平均未升高，这可能是由于其快速周转所致。在肝性脑病中，所有芳香族氨基酸的脑脊液浓度均升高，而在脓毒症患者中，仅苯丙氨酸水平升高。在肝性而非脓毒症性脑病中证实了中性氨基酸向脑内转运增加的证据，且这似乎与脑脊液谷氨酰胺浓度相关。肝性脑病患者的血氨水平升高，而脓毒症脑病患者的血氨水平未升高。我们的数据支持这样的假设：苯乙胺的代谢产物促成了全身性脓毒症和肝衰竭中的脑病；然而，这两种情况在其他方面存在差异。
