RESUMO
With the improving life expectancy of cystic fibrosis patients, new manifestations of the disease are emerging. Distal intestinal obstruction syndrome is one of the increasingly noted complications. Traditionally this syndrome was treated surgically. N-acetylcysteine is sometimes used as a non-surgical treatment option despite lack of definitive evidence for its efficacy and safety and not being mentioned in current treatment guidelines. The existing case reports suggest that N-acetylcysteine may have a place in therapy for older patients with incomplete distal intestinal obstruction syndrome to relieve the initial obstruction or following disimpaction to ensure clearance of remaining ileus and to prevent obstruction recurrence. In younger patients (e.g., <3 years of age), efficacy of N-acetylcysteine has been controversial and its use has been associated with drug-induced liver injury and hypernatremia. In the cases included in this review, 4% N-acetylcysteine was the formulation most commonly used. Since higher concentrations have been associated with increased adverse effects and mucosal injury, lower concentrations and dosages should be used when using N-acetylcysteine until further evidence becomes available. Proper administration technique and monitoring parameters are not well defined in current literature. Prospective, well-designed clinical trials are lacking and would be helpful to better define the role of N-acetylcysteine in distal intestinal obstruction syndrome.