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D G Oreopoulos

Publications and source records attributed to D G Oreopoulos.

At least 145 records · Page 8Linked to original sources
PubMed1991

Nutritional assessment of continuous ambulatory peritoneal dialysis patients: an international study.

We examined the nutritional status of 224 patients from six centers in Europe and North America to assess the incidence of protein-energy malnutrition. A "subjective nutritional assessment" was made, using 21 variables derived from history and clinical examination, or anthropometry and biochemistry. Eighteen patients (8%) were severely malnourished, 73 (32.6%) were mildly to moderately malnourished, and 133 (59.4%) did not show evidence for malnutrition. There was a higher incidence of mild to moderate malnutrition in diabetics than in nondiabetics. A statistical analysis identified 12 variables, seven objective and five subjective, that correlated with subjective nutritional assessment. Actual intercenter differences for the incidence of malnutrition were related to patient age, nutritional status at the commencement of continuous ambulatory peritoneal dialysis (CAPD), the length of time on CAPD, and residual renal function. Variables that were most frequently correlated with subjective nutritional assessment and with one another included plasma albumin, mid-arm muscle circumference (MAMC), weight loss, and the clinical judgement of muscle wasting and loss of subcutaneous fat. Loss of residual renal function correlated with muscle wasting and months on CAPD. Our data identified differences between the two sexes. In women there was a trend for more anorexia, greater weight loss from muscle wasting, and a larger decrease in albumin, whereas in men there was a more gradual decrease in nutritional status. Loss of residual renal function contributed to anorexia and symptoms of severe malnutrition.

Adolescent↗
PubMed1991

Lack of correlation between urea kinetic indices and clinical outcomes in CAPD patients.

We examined the predictive value of urea kinetics for patient outcomes in CAPD by measuring dialysis index (DI; a means of quantifying CAPD dose using urea kinetics), KT/V and normalized protein catabolic rate (PCRN) on 222 occasions in 76 new patients at the time of starting CAPD and at subsequent six month intervals. We investigated how these indices altered with time and in relation to each other, and how they correlated with a wide range of subsequent patient outcomes. DI, KT/V and PCRN all tended to decrease with time on CAPD (P less than 0.0004, less than 0.0001 and 0.0005, respectively). DI and KT/V were highly correlated with each other (r = 0.89, P less than 0.0001) and both correlated with PCRN (r = 0.57, P less than 0.0001 and r = 0.60, P less than 0.0001, respectively). DI and KT/V both correlated inversely with subsequent values for serum creatinine (P less than 0.0001), urea (P less than 0.0002), potassium (P less than 0.02) and phosphate (P less than 0.002), and directly with bicarbonate (P less than 0.0001). PCRN correlated inversely with serum creatinine (P less than 0.0002) and directly with urea (P less than 0.0001) and with the number of blood transfusions received (P less than 0.03). None of these indices correlated with levels of hemoglobin, PTH, alkaline phosphatase or albumin, or with nerve conduction velocity or any other subsequent clinical outcomes including death, technique failure, hospital days, peritonitis rate and subjective indices of fatigue, pruritus and insomnia. We conclude that the urea kinetic model is predictive of some biochemical outcomes but not of clinical outcomes in CAPD patients.

Adolescent↗
PubMed1991

Subcutaneous versus intraperitoneal insulin in the management of diabetics on CAPD: a review.

Intraperitoneal and subcutaneous routes of administration for diabetics on CAPD were compared. The comparison included: (1) Control of blood glucose concentration: both methods can provide satisfactory glycemic control for most patients. Changing the method of insulin administration is warranted when one method fails. (2) Effect on plasma insulin levels: intraperitoneal administration can produce a plasma insulin profile similar to the normal profile. This is unusual with subcutaneous administration. Consequences of hyperinsulinemia (hyperlipidemia, hypertension) seem, however, to be similar between the two methods of insulin administration. (3) Effect on peritoneal permeability: permeability characteristics are maintained unchanged, usually, with either method after long-term CAPD. However, insulin is mitogenic in vitro. Theoretically, intraperitoneal insulin could lead to peritoneal fibrosis. (4) Effect on infectious complications of CAPD: a difference in the rate of peritonitis or overall PD catheter-related infections has not been convincingly demonstrated between the two methods of insulin administration. Exit site and tunnel infections with staphylococcus aureus may be more frequent in diabetics receiving insulin subcutaneously. (5) Effect on hepatic structure and function: subcapsular hepatic steatosis was described in diabetics receiving insulin intraperitoneally. The clinical significance of this finding remains to be demonstrated. We conclude that both methods can be applied for insulin administration in diabetics on CAPD. The intraperitoneal method should be tried first in most instances. Prospective studies comparing the two methods are needed.

Diabetes Mellitus, Type 1↗
PubMed1991

Effects of chondroitin sulphate on fluid and solute transport during peritoneal dialysis in rats.

The effect of chondroitin sulphate (CS) on peritoneal fluid and solute transport was studied in rats undergoing peritoneal dialysis. In the presence of CS, net ultrafiltration increased, while absorption of glucose and horseradish peroxidase from the peritoneal cavity decreased. Albumin, used instead of CS, did not modify either fluid or solute transport. In in vitro experiments on isolated rabbit mesentery, CS decreased transmembrane water flow induced by hydrostatic pressure, and its effect was not fully reversed 60 minutes after "wash-out" of this glycosaminoglycan. We postulate that the polyanionic CS molecules are trapped in the peritoneal interstitium, thus decreasing its hydraulic conductivity and permeability, which in turn increases net fluid removal during peritoneal dialysis because of its slower absorption from the peritoneal cavity.

Albumins↗
PubMed1991

Is intraperitoneal tobramycin ototoxic in CAPD patients?

In 40 CAPD patients treated for peritonitis, the authors did a prospective study of ototoxic effects of intraperitoneal tobramycin. They evaluated cochlear function in pure-tone threshold audiograms over a range of frequencies from 250-10,000 Hz, in the speech-reception threshold test and in the speech-discrimination test. These tests were performed within 48 hours of initiation of tobramycin treatment and within 2 or 3 weeks of the drug's discontinuation. With the aminoglycoside doses used in this study, no statistical difference between the mean baseline and mean follow-up hearing levels was seen in these 40 patients. However, according to the standard criteria of ototoxicity, the hearing in 10 of 40 patients (25%) deteriorated after tobramycin, while it improved in seven patients (17.5%). In the remaining 23 (57.5%), hearing remained stable. With respect to the risk factors for ototoxicity such as advanced age, increased duration of treatment, elevated plasma aminoglycoside levels, concomitant treatment with other ototoxic drugs, pre-existing hearing loss, renal dysfunction and hyperthermia, no statistically significant difference was demonstrated between the patients with deteriorated, stable or improved hearing. The results of this study do not confirm that tobramycin given intraperitoneally to CAPD patients produces auditory toxicity. The hearing deterioration observed in 10 patients may be due to synergistic factors. The improvement observed in 7 patients could not be explained.

Audiometry, Pure-Tone↗
PubMed1991

Stimulation of mesothelial cells proliferation by endogenous growth factor(s).

We have attempted to determine whether human mesothelial cells (MC) have the power to influence their own proliferation. A serum-free medium was conditioned with the mesothelial monolayer for 24 hours and then applied to proliferating MC. Conditioned medium increased proliferation rate of MC. When the medium was heated at 60 degrees C for 60 minutes, the growth-promoting activity of the conditioned medium decreased by 50%, suggesting that MC produce at least 2 growth factors, 1 heat-labile and the other heat-stable. When MC were exposed continuously to a medium containing 90 mM glucose growth factor, production was decreased by 35%. However, when the cells were exposed to glucose only on alternate days, growth-factor production was similar to that in the control medium. On the other hand, MC exposed continuously for 10 days to 90 mM of glucose exhibited a weaker response to endogenous growth factor, even in a normotonic medium with low glucose concentration. Our results suggest that MC synthesize factor(s), which stimulate their own proliferation, and that high glucose concentrations interfere with this production and the subsequent action of growth factor.

Cell Division↗
PubMed1991

Single-dose pefloxacin pharmacokinetics and metabolism in patients undergoing continuous ambulatory peritoneal dialysis (CAPD).

Seven adult patients on continuous ambulatory peritoneal dialysis (CAPD) received one dose of pefloxacin, a novel quinolone antibiotic, orally and intravenously on two separate occasions to characterize the pharmacokinetics and metabolism of the drug. Concentrations of both pefloxacin and its active metabolite N-desmethyl-pefloxacin (norfloxacin) were measured in serum and dialysate by HPLC. Half-life, total body clearance and peritoneal clearance were determined. The overall elimination half-life was 19.9h. Relative to the IV dose the bioavailability following oral administration of pefloxacin was 76%. The mean serum and dialysate concentrations were similar up to 24 h after the oral or IV dose. After a 6-h dwell time the dialysate concentration of pefloxacin was 2.24 mg/L which is above the MIC90 for most bacteria responsible for peritonitis in CAPD patients. The peritoneal clearance of pefloxacin averaged 2.5 mL/min. Serum concentrations of the metabolite norfloxacin were less than 0.5 mg/L during the 24 h study period. We conclude that pefloxacin might be equally effective in the treatment of peritonitis of CAPD after oral or IV administration. Since the peritoneal clearance contributes insignificantly to the elimination of pefloxacin during CAPD, the proposed maintenance regimen of an oral or IV 400 mg dose/day seems to be a reasonable therapy for infections in CAPD patients.

Administration, Oral↗
PubMed1990

Fibrillary glomerulonephritis in a patient with metastatic carcinoma of the liver.

A 61-year-old women presented with nephrotic syndrome and progressive renal failure associated with metastatic adenocarcinoma of the liver. Renal biopsy revealed marked widening of the basement membrane and nonamyloidotic fibrillary deposits composed chiefly of polyclonal IgG. This is the first reported case of Congo-red-negative fibrillary glomerulopathy in association with adenocarcinoma of the liver.

Adenocarcinoma↗
PubMed1990

Peritonitis-related deaths in continuous ambulatory peritoneal dialysis (CAPD) patients.

A total of 636 episodes of peritonitis occurred in 440 patients who entered our continuous ambulatory peritoneal dialysis (CAPD) program from September 1977 to February 1988. Sixteen patients (8 male and 8 female, aged 37-77 years) died during an episode of peritonitis (fatality rate 2.5%). They had been on CAPD for 3 to 105 (average 39) months. Six of them were diabetics. The peritonitis rate among these 16 patients were 1 episode per 12 patient months, while the corresponding figure for the whole (440) CAPD population was 14 patient months. Risk factors present in the 16 patients were: cardiovascular disease (12), cerebrovascular accident (2) peripheral artery disease (1) and pulmonary fibrosis (1). Fever and leukocytosis were present on admission in 11 patients, while total serum proteins and albumin were significantly lower (p less than 0.001) than the corresponding values before peritonitis (56 +/- 8 vs. 65 +/- 5). Staph. aureus was isolated in 8 patients (50%), multiple organisms in 6, Pseudomonas and Candida albicans in 1 each. An abdominal abscess was found in 4 (25%) patients. The peritoneal catheter was removed between the 5th and 10th day in 6 and after the 10th day in 7 patients. Peritonitis with sepsis was the cause of death in 13 patients. Contributing factors were cardiovascular accident in 9, uremic coma in 2, extensive GI bleeding in 2, GI perforation in 2, intestinal infarction in 1, and pneumonia in 2 patients. We conclude that the risk of peritonitis-related death in CAPD patients is increased with Staph. aureus or multibacterial peritonitis. Contributing factors are concomitant cardiovascular disease and delayed (greater than 5 days) catheter removal.

Cardiovascular Diseases↗
PubMed1990

Six-month overnight intraperitoneal amino-acid infusion in continuous ambulatory peritoneal dialysis (CAPD) patients--no effect on nutritional status.

The long-term effect of an AA solution based on Travasol, a solution for total parenteral nutrition, given intraperitoneally over a 6-month period was studied in 5 patients 22 to 75 years old, having been on continuous ambulatory peritoneal dialysis (CAPD) for 3 to 57 months. A low oral protein intake (less than 0.8 g/kg bw/day) and/or a low serum albumin (less than 35 g/L) were used as inclusion criteria. Two liters of 1% AA solution were infused overnight, while a glucose Dianeal was used for the other exchanges. During the study, BUN increased from 22.04 mM/L to 28.06 mM/L the first month and remained at these levels, indicating the increased protein intake. However, average oral total energy and protein intake, body weight (bw), serum creatinine, cholesterol, triglycerides, total proteins, albumin, transferrin, skinfold thickness, total body potassium, and plasma AA levels remained basically unchanged. The average total body nitrogen decreased from 1.746 to 1.554 Kg, but this decrease did not reach statistical significance (p greater than 0.05). We conclude that intraperitoneal overnight administration of 2 L of 1% AA based on Travasol over 6 months did not improve the nutritional status of CAPD patients. This ineffectiveness might be due to the AA composition of the solution, the timing of administration, or to a low caloric intake and/or that our patients were not severely malnourished.

Amino Acids↗
PubMed1990

Genital swelling as a surgical complication of continuous ambulatory peritoneal dialysis.

Genital edema was seen as a complication of continuous ambulatory peritoneal dialysis (CAPD) in 18 patients, who accounted for 4 per cent of all patients on CAPD. In the majority of patients, the swelling developed suddenly and painlessly in the scrotum, penis or labia majora. Some of the patients noticed ultrafiltration failure. In the majority of these patients, this was a result of fluid leakage through the patent processus vaginalis. In one female patient, fluid leaked through the implantation site of the catheter. A computed tomographic scan using contrast media is a useful diagnostic tool in identifying the side of the defect in patients with generalized scrotal or penile edema. Surgical repair of the hernia and the hole in the processus vaginalis or hernia sac prevented recurrence. A trial of temporary discontinuation of CAPD or intermittent peritoneal dialysis using small volumes of dialysis fluid prevented recurrence while reinstituting CAPD in patients with normal findings from contrast studies. Intermittent peritoneal dialysis using low volumes of dialysis fluid with stepwise increase prevented recurrence while reinstituting CAPD two to three weeks after surgical repair.

Adult↗
PubMed1989

Urine citrate and renal stone disease.

Calcium stone disease is attributable to supersaturation of the urine with calcium and other salts, the presence of substances that promote crystallization and a deficiency of inhibitors of crystallization. Citrate is a potent inhibitor of calcium oxalate and calcium phosphate stone formation whose excretion is diminished in some patients with stone disease owing to idiopathic causes or secondary factors such as bowel disease and use of thiazides. The pH within the proximal tubule cells is an important determinant of citrate excretion. Multivariate analysis has shown that the urine concentrations of calcium and citrate are the most important factors in stone formation. In uncontrolled studies potassium citrate, which increases urinary citrate excretion, appears to be promising as a therapeutic agent for patients with stone disease and hypocitraturia refractory to other treatment. On the other hand, there are potential drawbacks to sodium alkali therapy, such as the precipitation of calcium phosphates.

Citrates↗