[Cerebral magnetic resonance spectroscopy in patients with hepatic encephalopathy: analysis before and after liver transplantation].
OBJECTIVE
To determine the metabolite levels (myo-inositol [MI], choline [Cho], glutamate [Glx], creatine [Cr] and N-acetylaspartate [NAA]) visible on magnetic resonance spectroscopy in patients with chronic hepatic failure, before and after liver transplantation and to correlate these data with results of neuropsychiatric tests and clinical findings.


METHODS
Twenty five patients with chronic hepatic failure from the Liver Transplantation Unit of the Federal University of Parana were prospectively studied. Patients were submitted to clinical evaluation and magnetic resonance spectroscopy. Thirty healthy volunteers also submitted to the same evaluations. Sixteen of the 25 patients were evaluated after liver transplantation.


RESULTS
Before liver transplantation, significant reductions in MI/Cr and Cho/Cr and a significant increase in Glx/Cr were observed in patients with hepatic encephalopathy compared with healthy subjects. The Ross's criteria for spectroscopic diagnosis of the hepatic encephalopathy (MI/Cr and Cho/Cr lower than 2 SD of controls) demonstrated a sensitivity of 61.54%, specificity of 91.67% and accuracy of 76%, further Cho/Cr was the best parameter. Spectroscopy after liver transplantation showed changes in the metabolite ratios compared with the pretransplantation status.


CONCLUSIONS
Magnetic resonance spectroscopy permits an accurate diagnosis of hepatic encephalopathy. Improvement of metabolic ratios after liver transplantation suggests an important role of MI and Cho in the development of hepatic encephalopathy.
Hospital de Clínicas, Universidade Federal do Paraná, Curitiba, PR, Brasil. gjschulz@hotmail.com
Gustavo Justo
GJ
Schulz
Julio Cézar Uili
JC
Coelho
Jorge Eduardo Fouto
JE
Matias
Antônio Carlos Ligocki
AC
Campos
Danielle Duck
DD
Schulz
Guilherme Augusto
GA
Bertoldi
D000328:Adult; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000032:analysis; D001921:Brain / Q000378:metabolism*; D016022:Case-Control Studies; D002794:Choline / Q000032:analysis; D003401:Creatine / Q000032:analysis / Q000096:biosynthesis; D004734:Energy Metabolism / Q000502:physiology*; D005260:Female; D006501:Hepatic Encephalopathy / Q000378:metabolism* / Q000601:surgery; D006801:Humans; D007294:Inositol / Q000032:analysis; D016031:Liver Transplantation; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies
D001224:Aspartic Acid; D007294:Inositol; C000179:N-acetylaspartate; D003401:Creatine; D002794:Choline