Evaluation of cognitivity, proinflammatory cytokines, and brain magnetic resonance imaging in minimal hepatic encephalopathy induced by cirrhosis and extrahepatic portal vein obstruction.

Background and Aims Minimal hepatic encephalopathy (MHE) is the mildest form of hepatic encephalopathy (HE) and is characterized by deficits in neurocognitive performance without any clinical symptoms of HE. In the current study, we aim to evaluate and compare the neurocognitive, biochemical, and brain magnetic resonance (MR) imaging changes between patients with cirrhotic MHE and extrahepatic portal vein obstruction (EHPVO) MHE. Methods Thirty-three cirrhotic and 14 EHPVO patients were diagnosed with MHE and were included in the analysis along with 24 normal healthy volunteers. All subjects underwent MR imaging including diffusion tensor imaging and proton MR spectroscopy (¹H-MRS) followed by cognitive assessments, critical flicker frequency (CFF) measurements, quantification of blood ammonia, and serum proinflammatory cytokine levels. Results We observed abnormal neurocognitive functions and CFF measurements in both cirrhotic MHE and EHPVO MHE patients as compared with controls. Significantly increased blood ammonia, serum proinflammatory cytokines (IL-6, TNF-α) level, mean diffusivity in multiple brain sites, ¹H-MRS derived glutamate/glutamine (Glx)/creatine (Cr), and significantly decreased ¹H-MRS derived myo-inositol/Cr were observed in both cirrhotic MHE and EHPVO MHE compared with those of controls. Choline/Cr level was significantly decreased in cirrhotic MHE as compared with controls and EHPVO MHE. Conclusions Cirrhotic MHE showed more severe changes on mean diffusivity in multiple brain sites and inflammation as compared with EHPVO MHE. This study confirms that there are significant difference in neurocognitive, biochemical, and MR profile between cirrhotic MHE and EHPVO MHE, which may help to understand the pathophysiologies of these two types of MHE and may contribute to improve their clinical managements. [ABSTRACT FROM AUTHOR]