The effect of N-acetylcysteine on proteinuria and markers of tubular injury in non-diabetic patients with chronic kidney disease. A placebo-controlled, randomized, open, cross-over study.

BACKGROUND

Inhibition of the renin-angiotensin-aldosterone system with angiotensin-converting enzyme inhibitors (ACEI) and/or angiotensin II subtype 1 receptor antagonists (ARB) constitutes a strategy in the management of patients with chronic kidney disease. There is still no optimal therapy which can stop the progression of chronic kidney disease. Antioxidants such as N-acetylcysteine (NAC) have been reported as a promising strategy in this field.

METHODS

In a placebo-controlled, randomized, open, 2-period cross-over study, we evaluated the influence of NAC (1,200 mg/day) added to renin-angiotensin-aldosterone system blockade on proteinuria and surrogate markers of tubular injury and renal fibrosis in 20 non-diabetic patients with proteinuria (0.4-6.36 g/24 h) with normal or decreased kidney function (estimated glomerular filtration rate 61-163 ml/min). Subjects entered the 8-week run-in period during which the therapy using ACEI and/or ARB was established with blood pressure below 130/80 mm Hg. Next, patients were randomly assigned to 1 of 2 treatment sequences: NAC/washout/placebo or placebo/washout/NAC. Clinical evaluation and laboratory tests were performed at the randomization point and after each period of the study.

RESULTS

No significant changes in laboratory tests were observed.

CONCLUSION

NAC had no effect on proteinuria, surrogate markers of tubular injury or renal fibrosis in non-diabetic patients with chronic kidney disease.