Predictive value of induced hyperammonaemia and neuropsychiatric profiling in relation to the occurrence of post-TIPS hepatic encephalopathy.
Hepatic encephalopathy (HE) occurs in 20-50% of patients after transjugular intrahepatic portosystemic shunt (TIPS) placement. Older age, HE history and severe liver failure have all been associated with post-TIPS HE but it remains difficult to identify patients at risk. The aim of the present pathophysiological, pilot study was to assess the role of induced hyperammonaemia and associated neuropsychological and neurophysiological changes as predictors of post-TIPS HE. Eighteen TIPS candidates with no overt HE history (56 ± 8 yrs., MELD 11 ± 3) underwent neurophysiological [Electroencephalography (EEG)], neuropsychological [Psychometric Hepatic Encephalopathy Score (PHES) and Scan tests], ammonia and sleepiness assessment at baseline and after the induction of hyperammonaemia by an oral amino acid challenge (AAC). Pre-AAC, 17% of patients had abnormal EEG, 5% abnormal PHES, and 33% abnormal Scan performance. Post-AAC, 17% had abnormal EEG, 0% abnormal PHES, and 17% abnormal Scan performance. Pre-AAC, ammonia concentrations were 201 ± 73 μg/dL and subjective sleepiness 2.5 ± 1.2 (1-9 scale). Post-AAC, patients exhibited the expected increase in ammonia/sleepiness. Six months post-TIPS, 3 patients developed an episode of HE requiring hospitalization; these showed significantly lower pre-AAC fasting ammonia concentrations compared to patients who did not develop HE (117 ± 63 vs. 227 ± 57 μg/dL p = 0.015). They also showed worse PHES/Scan performance pre-AAC, and worse Scan performance post-AAC. Findings at 12 months follow-up (n = 5 HE episodes) were comparable. In conclusion, baseline ammonia levels and both pre- and post-AAC neuropsychiatric indices hold promise in defining HE risk in TIPS candidates with no HE history.
['Senzolo|Marco|M|', 'Zarantonello|Lisa|L|', 'Formentin|Chiara|C|', 'Orlando|Costanza|C|', 'Beltrame|Raffaello|R|', 'Vuerich|Anna|A|', 'Angeli|Paolo|P|', 'Burra|Patrizia|P|', 'Montagnese|Sara|S|0000-0003-2800-9923']
D000368:Aged D000596:Amino Acids D000641:Ammonia D005260:Female D006501:Hepatic Encephalopathy D006801:Humans D022124:Hyperammonemia D008103:Liver Cirrhosis D008297:Male D008875:Middle Aged D009483:Neuropsychological Tests D010865:Pilot Projects D019168:Portasystemic Shunt, Transjugular Intrahepatic D011237:Predictive Value of Tests D011930:Reaction Time D000077260:Sleepiness
Ammonia Oral amino acid challenge Cirrhosis Prognosis