N-Acetylcysteine in the Management of Spontaneous Bacterial Peritonitis

Spontaneous bacterial peritonitis (SBP) is one of the most serious infectious complications of liver cirrhosis and ascites. It affects approximately 10-30% of hospitalized patients with decompensated cirrhosis and carries an in-hospital mortality of 20-40% despite appropriate antimicrobial therapy. SBP results from bacterial translocation across the intestinal mucosa together with cirrhosis-associated immune dysfunction, leading to impaired bacterial clearance and exaggerated systemic inflammation. Current international guidelines recommend immediate empirical antibiotic therapy together with intravenous human albumin to reduce the incidence of acute kidney injury (AKI), hepatorenal syndrome, and mortality.

Although this strategy has substantially improved outcomes, treatment failure, persistent infection, renal dysfunction, acute-on-chronic liver failure (ACLF), and early mortality remain common, indicating that currently available therapy does not adequately address all pathogenic mechanisms of SBP. Increasing evidence suggests that oxidative stress is a central contributor to the progression of bacterial infections in cirrhosis. Excessive production of reactive oxygen species aggravates hepatocellular injury, endothelial dysfunction, immune dysregulation, and renal impairment, thereby amplifying systemic inflammatory responses during SBP. Consequently, therapeutic strategies targeting oxidative stress may improve host defense while limiting organ injury.

N-acetylcysteine (NAC) is a precursor of glutathione and one of the most extensively studied antioxidant agents in clinical medicine. Besides restoring intracellular glutathione stores, NAC exerts anti-inflammatory, endothelial-protective, and immunomodulatory effects through inhibition of oxidative stress and pro-inflammatory cytokine production. On the other hand, experimental studies have further demonstrated that NAC can inhibit bacterial biofilm formation, enhance antibiotic penetration, and potentiate antimicrobial activity against several clinically important bacterial pathogens.

Despite these promising biological properties, the therapeutic role of NAC in active SBP has not been established. Previous data have primarily evaluated NAC for hepato- or renal protection in liver disease. While its potential role as an adjunctive antibacterial therapy during active SBP has not been investigated in adequately designed randomized controlled trials. Therefore, the present study will evaluate whether adjunctive NAC improves early treatment response and reduces subsequent organ dysfunction and short-term adverse outcomes.