N-acetylcysteine in non-acetaminophen-induced acute liver failure: a systematic review and meta-analysis of prospective studies

Introduction
There are discordant reports on N-acetylcysteine (NAC) efficacy in non-acetaminophen acute liver failure (ALF).

Aim
To determine whether NAC is beneficial in non-acetaminophen ALF.

Material and methods
We performed a systemic review and meta-analysis of published data to address the question. PubMed and MEDLINE were searched using the terms non-acetylcysteine and ALF due to non-acetaminophen, viral infection, drug-induced or autoimmune hepatitis. The primary outcome was overall mortality. Secondary outcomes were transplant-free survival and length of hospital stay. Risk ratios were calculated using a random model for meta-analysis.

Results
A total of 672 patients were included in this meta-analysis from 5 prospective studies (NAC group: n = 334; control group: n = 338). Viral hepatitis (45.8% vs. 32.8%) followed by drug-induced liver injury (24.6% vs. 27.5%), indeterminate cause (13.2% vs. 21.6%) and autoimmune hepatitis (6.6% vs. 8.9%) were the most common etiologies of ALF in the treatment group and control group respectively. Treatment with N-acetylcysteine improved the transplant-free survival significantly (55.1% vs. 28.1%; RR = 0.56; 95% CI: 0.33–0.94) whereas the overall survival was not improved with NAC (71% vs. 59.8%; RR = 0.73; 95% CI: 0.48–1.09). The NAC treatment was associated with shorter hospital stay (Standard difference in means (SMD) = –1.62; 95% CI: –1.84 to –1.40, p < 0.001).

Conclusions
The treatment of patients with acute liver failure with N-acetylcysteine improved transplant-free survival and length of stay.