Nitric oxide plays an important role in mediating the inflammatory process. The aim of this study was to evaluate if
nitric oxide production was increased during
peritonitis in patients receiving
continuous ambulatory peritoneal dialysis (
CAPD), and the association with the prognosis. The study population comprised 21 patients with 22 episodes of
peritonitis. Fifteen patients without
peritonitis were controls.
Nitrate was measured by HPLC and
nitrite by the Griess method, to reflect
nitric oxide production. Peritoneal
dialysate effluent and plasma were collected from six patients during
peritonitis and 1 week
after treatment to study changes in
dialysate:plasma ratio. In 15 patients,
nitrite was measured during
peritonitis and every 3 days for 2 weeks or until normalized for evolutional changes. The
dialysate:plasma ratios of
nitrate and
nitrite during
peritonitis were reduced 26% and 41.5%, respectively, after 1 week of treatment, indicating the peritoneal production of
nitric oxide during
peritonitis. In the evolutional study, a 5.1-fold increase of peak
nitrite levels in bacterial
peritonitis (n = 13) and a 2.5-fold increase in fungal
peritonitis (n = 3) were observed compared to controls.
Nitrite gradually declined to control levels (9.3 +/- 7.2 days) after effective
antibiotic treatment, but took longer than to normalize leukocyte count in the peritoneal
dialysate effluent (3.9 +/- 1.9 days). In four patients with refractory
peritonitis (
Candida infection in three,
Acinetobacter infection in one), the
nitrite levels remained elevated 2-fold despite treatment, and the
catheters were removed. It is concluded that
nitrite levels in peritoneal
dialysate effluent may serve as a marker to assess treatment efficacy in
CAPD patients with
peritonitis.