Morphologic characteristics of macroscopic peritoneal finding in patients with peritoneal dialysis.

Peritoneal dialysis (PD) has been an attractive treatment for end-stage kidney disease. Long-term exposure to the PD solution creates functional and morphological alterations, and these alterations diminish the efficacy of PD. It is important to establish an evaluation of the changes in PD patients and strategies for the prevention of PD damage and encapsulating peritoneal sclerosis (EPS). We determined the relationship between clinical findings and macroscopic morphological findings by laparoscopy in patients receiving PD. Macroscopic intraperitoneal findings were recorded at the PD catheter removal in 23 PD patients. We examined macroscopic morphological findings such as fibrin deposition, peritoneal turbidity, vasculopathy, adhesion and calcification in both parietal and visceral peritoneum of upper and lower peritoneal cavities, and assessed the score semi-quantitatively. We then evaluated the relationship between the morphological score and clinical findings, especially observational parts and findings in EPS patients. The total macroscopic score increased with PD duration. Peritoneal turbidity, fibrin deposition, and calcification were observed in the whole peritoneal cavity. Scores of fibrin deposition, turbidity, and calcification increased with PD duration. Vasculopathy in the parietal peritoneum was more serious compared with that in the visceral peritoneum, but there was no difference in the vasculopathy between the upper and lower areas. A characteristic of the macroscopic findings in EPS patients was peritoneal calcification in this study. It appears that macroscopic findings using laparoscopy is significant in evaluating the degree of the peritoneum damage and predicting EPS development.

Effects of Cardiac Function with Postoperative Arteriovenous Fistula Blood Flow in Patients with Hemodialysis.

BACKGROUND/AIMS: This study was aimed at evaluating the effect of cardiac function with postoperative arteriovenous fistula (AVF) blood flow in hemodialysis (HD) patients. METHODS: A total of 45 HD patients were examined at the Juntendo University Hospital. The AVF blood flow was measured using ultrasonography, and the cardiac function was measured using echocardiography. Correlation between these parameters and the rate of change in body weight (BW) was analyzed. RESULTS: The number of postoperative days significantly correlated with the AVF blood flow, and it positively correlated with the stroke volume (SV). The postoperative AVF blood flow in patients with reduced ejection fraction (EF) was lower than that in patients with normal EF. The rate of change of BW negatively correlated with that of SV, positively correlated with cardiac output (CO), and positively correlated with CO in patients with an AVF blood flow of more than 1,000 mL/min. CONCLUSION: It appears that the cardiac function can be improved by controlling the BW even in patients with high AVF blood flow.

Morphological characteristics in peritoneum in patients with neutral peritoneal dialysis solution.

Peritoneal dialysis solution (PDS) plays a role in functional and morphological damage to the peritoneum. This study aimed to clarify the effect of neutral PDS in preventing morphological changes by assessing peritoneal damage and comparing morphological alterations between PD patients treated with neutral PDS and acidic PDS. Sixty-one patients participated from seven hospitals. All patients were treated with neutral PDS excluding icodextrin, during their entire PD treatment, and experienced no episode of peritonitis. The thickness of submesothelial compact (SMC) zone and the presence of vasculopathy in the anterior parietal abdominal peritoneum were assessed. The impact of icodextrin, hybrid therapy, and peritoneal rest and lavage in morphological alterations were determined. There was no significant difference in the average SMC thickness between neutral and acidic PDS. The vessel patency in patients using neutral PDS was significantly higher compared to that in acidic PDS at any time during PD. There were no significant suppressive effects from interventions or use of icodextrin with respect to peritoneal morphological injury. A monolayer of mesothelial cell was observed in approximately half the patients, especially in their receiving lavage patients. Neutral PDS, accompanied by other preventive approaches against peritoneal injury, might suppress the development of peritoneal morphological alterations.

Comparison between the fixation of peritoneal dialysis catheters to the peritoneal wall and the conventional placement technique: clinical experience and follow-up of a new implant technique for peritoneal dialysis catheters.

Peritoneal dialysis (PD) catheters often become severely dislocated, which may lead to malfunction. With the aim of preventing this complication, we have developed a simple method of fixing the catheter downwards in the peritoneal cavity (fixation technique), a technique that does not require a laparoscope. Sixteen patients were implanted using the conventional placement technique and 25 patients were implanted using the fixation technique. The location of the catheter tip was classified from grade 1 (downward, normal) to 5 (dislocated). The frequency of dislocation (defined as the extended time and/or decrease in volume when draining the PD solution) was measured for both the fixation technique and conventional placement technique. There was a significant difference in grade between the fixation technique (2.72 ± 1.01) and conventional technique (3.92 ± 1.31). The time until first dislocation was significantly different between the fixation technique (59.3 ± 48.1 days) and conventional technique (8.8 ± 14.6 days). The time until any dislocation was significantly different between the fixation technique (69.2 ± 41.9 days) and conventional technique (12.9 ± 13.7 days). Complications were not significantly different between the fixation technique and conventional technique. The fixation technique appears to be simple, safe, and useful for preventing severe dislocation and for lengthening the time until dislocation in PD patients.

Accumulation of advanced glycation end products and beta 2-microglobulin in fibrotic thickening of the peritoneum in long-term peritoneal dialysis patients.

Characteristics of pathological alterations in long-term peritoneal dialysis (PD) are thickening of submesothelial compact (SMC) zone, small-vessel vasculopathy, and loss of mesothelial cells. Bioincompatible PD fluid plays crucial roles in peritoneal injury. Encapsulating peritoneal sclerosis (EPS), a rare and serious complication, occurred in patients on long-term PD or frequent peritonitis episodes, and ~50 % of EPS developed after PD cessation. We hypothesized that PD-related peritoneal injury factors induced by bioincompatible PD fluid accumulated in the peritoneum and might induce EPS. We therefore examined the accumulation of advanced glycation end products (AGE) and beta 2-microglobulin (ß2M) in peritoneum and evaluated the relationship between their accumulation, clinical parameters, and outcome after PD cessation. Forty-five parietal peritoneal specimens were obtained from 28 PD patients, 14 uremic patients, and three patients with normal kidney function. The peritoneal equilibration test was used for peritoneal function. AGE- and ß2M-expressing areas were found in vascular walls, perivascular areas, and the deep layer of the SMC in short-term PD patients and extended over the entire SMC in long-term patients. Peritonitis and prolonged PD treatment aggravated peritoneal thickening and the proportion of AGE-expressing areas. The proportion of ß2M-expressing areas was increased in long-term PD patients. Thickening of the SMC and the proportions of AGE- and ß2M-expressing areas were not related to ascites or EPS after PD withdrawal. It appears that the increased proportion of AGE and ß2M deposition induced by long-term exposure of PD fluid may be a marker of peritoneal injury.

Differentiation of bone marrow-derived cells into regenerated mesothelial cells in peritoneal remodeling using a peritoneal fibrosis mouse model.

Marked thickening of the peritoneum and vasculopathy in the submesothelial compact zone have been reported in long-term peritoneal dialysis patients. Bone marrow (BM)-derived cell lines are considered to be useful tools for therapy of various diseases. To clarify the role of BM-derived cells in the peritoneal fibrosis (PF) model, we analyzed several lineages of cells in the peritoneum. BM cells from green fluorescent protein (GFP) transgenic mice were transplanted into naïve C57Bl/6 mice. Chlorhexidine gluconate (CG) was injected intraperitoneally to induce PF. Immunohistochemical analysis was performed with parietal peritoneum using anti-Sca-1 or -c-Kit and -GFP antibodies. Isolated BM cells were also transplanted into the CG-stimulated peritoneum. BM-derived cells from GFP transgenic mice appeared in the submesothelium from days 14 to 42. Both GFP- and stem cell marker-positive cells were observed in the submesothelium and on the surface. Isolated c-Kit-positive cells, transplanted into the peritoneal cavity, differentiated into mesothelial cells. In this study, we investigated whether or not BM-derived cells play a role in the repair of PF and immature cells have the potential of inducing repair of the peritoneum. The findings of this study suggest a new concept for therapy of PF.