Protein-losing enteropathy is associated with peritoneal functional abnormalities in peritoneal dialysis patients

Objective: To evaluate the relationship between acquired peritoneal transpo rt disorders and the presence of protein-losing enteropathy (PLE), and thei r contribution to the protein malnutrition in peritoneal dialysis (PD) pati ents. Patients and Methods: We studied 31 clinically stable PD patients that rece ived a fat overload diet for 3 days. We measured intestinal absorption of f ecal fat (normal < 6 g/24-hour stool) and nitrogen (normal < 2 g/24-hr stoo l), intestinal protein permeability [fecal clearance of alpha(1)-antitrypsi n (C alpha(1)AT) (normal < 12 mL/24-hr stool)], and nutritional markers [no rmalized protein nitrogen appearance (nPNA), half-life medium-term proteins , and body mass index]. Peritoneal solute transport was measured by mass tr ansfer coefficient (MTC), and water transport by peritoneal ultrafiltration (UF) capacity. To define protein maldigestion it was necessary to find hig h fecal nitrogen values with normal C alpha(1)AT; PLE was defined when both values were elevated. Results: High fecal nitrogen (mean 2.1 +/- 1 g/24-hr stool) and fat (mean 5 .8 +/- 3.6 g/24-hr stool) were found in 15 patients; 6 patients had high C alpha(1)AT levels (PLE). These 6 patients showed a worse nutritional status : lower albumin (3.57 +/- 0.57 g/dL vs 3.98 +/- 0.38 g/dL, p < 0.05) and tr ansferrin (243 +/- 70 mg/dL vs 272 +/- 44.3 mg/dL, p < 0.05), as well as lo wer triglycerides (131.3 +/- 31.7 mg/dL vs 187 +/- 116 mg/dL, p < 0.05). Hi gher urea MTCs were found in 10 patients, normal in 7, and lower in 14. Hig her creatinine MTCs were found in 8 patients, normal in 15, and lower in 8. Normal peritoneal UF capacity was found in 25 and lower in 6 patients. The se 6 patients showed higher urea and creatinine MTCs and C alpha(1)AT. A po sitive linear correlation between C alpha(1)AT, urea MTC (r = 0.56, p < 0.0 1), and creatinine MTC (r = 0.46, p < 0.01) was found. A similar situation occurred between C alpha(1)AT, fecal fat (r = 0.45, p < 0.05), and fecal ni trogen (r = 0.43, p < 0.05). Thirteen patients with previous history of per itonitis showed higher C alpha(1)AT than those without peritonitis (10.2 +/ - 8 mL/24-hr stool vs 5.2 +/- 4.4 mL/24-hr stool, p < 0.05). Conclusions: We confirm that protein and fat malabsorption, maldigestion, a nd PLE are present in some PD patients. Higher fecal C alpha(1)AT is associ ated with malnutrition and poorer showings of the viability markers of peri toneal membrane function.