Clinical Pharmacology of Hyperammonemia by Sodium Valproate and Carbamazepine in People Living with HIV

Abstract

Introduction

Hyperammonaemia (HA) is observed in decompensated liver disease. The picture of hyperammonemic encephalopathy in non-cirrhotic patients was reported mostly associated with valproic acid. There are few reports of hyperammonemia in people living with human immunodeficiency virus (PLHIV) and they are associated with other comorbidities and few with antiretrovirals (HAART), but not as adverse drug reactions associated with psychotropic drugs associated with the virus.

Objective

Report of cases of PLHIV in HARRT with hyperammonemia, its clinical impact and ammonium levels.

Materials and Methods

We report 67 PLHIV in treatment with HAART, negative viral loads, psychopharmacological treatment with valproic acid (n=45) or carbamazepine (n=22). Exclusion criteria were = HCV, HBV and alcohol consumption disorder (current or recent history) and decompensated liver pathology. We apply scales to evaluate side effects (UKU), subjective adherence (DAI), daily life activities (Barthel Index), liver severity (Child-Pugh Classification) and degrees of hepatic encephalopathy (West Haven Scale). The ethical-legal requirements were met. Results: 26.86% presented hyperammonemia, among which 38.88% was symptomatic. The clinical presentation was heterogeneous with a higher prevalence of gastrointestinal and cognitive alterations; the most severe cases presented alterations of the sensorium and 1 case of convulsions. We recorded a greater symptomatic severity with carbamazepine (average ammonia =104.4 pmol/L), but a higher prevalence of non-symptomatic hyperammonemia with valproic acid (62.3 pmol/L). The time of onset of symptoms was lower with carbamazepine, but the time until its decrease was higher with valproic acid.

Conclusions

We observed a higher prevalence of hyperammonemia and associated symptomatology in PLHIV with HAART medicated with carbamazepine. The significant percentage of this adverse drug reaction suggests a biochemical, perhaps preventive, control.