ABC de la diálisis peritoneal en pediatría / ABC of the peritoneal dialysis in pediatrics

Resumen: La enfermedad renal crónica terminal (ERCT) tiene una incidencia de 5,5 a 9 ppm, y una prevalencia de 23 a 65 ppm en menores de 15 años. La diálisis peritoneal (DP) crónica representa en pediatría la terapia de reemplazo renal más usada, previo al trasplante renal. Existen 2 tipos de DP crónicas, manual (DPCA) y automatizada (DPA), cuya elección se basa en las características del peritoneo eva luado mediante el test de equilibrio peritoneal (PET), que divide a los pacientes en transportadores altos (intercambio rápido), promedio alto, promedio bajo, y bajos (intercambio lento). Este test eva lúa básicamente el transporte de solutos, al cual se ha sumado el MiniPET, que evalúa el transporte peritoneal de agua libre. Se debe igualmente determinar la cuantía de diálisis (Kt/V), que representa la dosis de diálisis aplicada, con un valor mínimo sugerido de 1,7, relacionado a la morbimortalidad. Estos parámetros deben ser evaluados periódicamente para ajustar la DP, y cada vez que se sospeche una depuración o ultrafiltración inadecuadas. El objetivo de esta revisión es entregar conceptos bási cos sobre fisiología del transporte peritoneal, modalidades de DP, evaluación del transporte de agua y solutos peritoneal, y el cálculo de la dosis de diálisis para una diálisis ajustada a las necesidades de cada paciente, como también revisar los mecanismos de corrección y ajuste del procedimiento cada vez que se requiera.

Abstract: End-stage renal disease (ESRD) has an incidence of 5.5 to 9 pmp, and a prevalence of 23 to 65 pmp in children under 15 years of age. Chronic peritoneal dialysis (PD) represents the most widely used renal replacement therapy in children before kidney transplantation. There are two PD modalities, the manual one (CAPD) and the automated one (APD). The choice is based on the peritoneum characteristics, evaluated through the peritoneal equilibrium test (PET), which divides patients into high transporters (rapid exchange membrane), high average, low average, and low transporters (slow exchange membrane). This test basically evaluates the solutes transport rate, and the MiniPET has been added which evaluates peritoneal free water transport. The amount of dialysis (Kt/V), which represents the dose of dialysis administered also must be evaluated to assure a minimal value of 1.7 related to morbidity and mortality. These parameters should be evaluated periodically to ad just the PD and whenever suspected an inadequate clearance or ultrafiltration. The objective of this review is to provide basic concepts on peritoneal transport physiology, PD modalities, free water transport and peritoneal solute transport evaluation, and the dialysis dose to be applied according to the patient's needs, as well as reviewing the correction mechanisms and procedure adjustment whenever required.

Análisis de pacientes en diálisis peritoneal: factores clínico-epidemiológicos y tipo de transporte peritoneal con recambio hipertónico / Analysis of patients in peritoneal dialysis: clinical-epidemiologic factors and peritoneal transport type with

Resumen Introducción: la diálisis peritoneal ha sido una terapia efectiva para los pacientes con falla renal terminal. Objetivo: determinar las características de la población y el tipo de transporte peritoneal (utilizando una solución dializante hipertónica). Materiales y métodos: estudio descriptivo transversal en pacientes del Servicio de Nefrología del Hospital Escuela Universitario de Tegucigalpa, durante el período comprendido entre el 1 de octubre al 15 de noviembre de 2016. Resultados: la nefropatía diabética fue identificada como la causa de nefropatía crónica en 18 (42.9 %) pacientes; seguida de la nefropatía hipertensiva, con 14 (33.3 %), y la nefropatía mesoamericana, con 8 (19.0 %). El tipo de transporte peritoneal más frecuente fue el promedio alto, en 21 (50.0 %) de los pacientes; seguido del promedio bajo, con 12 (28.6 %); el transporte bajo, con 7 (16.7 %); y el transporte alto, con 2 (4.8 %). Discusión: en Centroamérica, durante los últimos años, ha habido un aumento de incidencia de la enfermedad renal en trabajadores provenientes de la costa pacífica, especialmente varones agricultores sin factores de riesgo. Esto constituye una epidemia de la nefropatía mesoamericana. Existe una relación entre el aumento de la transferencia de solutos y la disminución de la ultrafiltración con el paso del tiempo. Conclusiones: la nefropatía mesoamericana es una causa emergente de enfermedad en la región. No se encontró relación entre el tiempo prolongado de diálisis peritoneal, o el antecedente de peritonitis, y un transporte peritoneal bajo.

Abstract Introduction: Peritoneal dialysis has been an effective therapy in the management of patients with end-stage renal failure. Objective: To determine the characteristics of the population and the type of peritoneal transport using hypertonic dialyzing solution. Methods and Materials: Prospective and cross-sectional study in patients of the Nephrology Service of the Hospital Escuela Universitario of Tegucigalpa during the period from October 1 to November 15, 2016. Results: Diabetic nephropathy was associated as the cause of chronic kidney disease in 18 (42.9%) patients, followed by nephropathy hypertensive disease with 14 (33.3%) and Mesoamerican nephropathy with 8 (19.0%). The most frequent type of peritoneal transport was the high average in 21 (50.0%) of the patients, followed by the low average with 12 (28.6%), low transport with 7 (16.7%) and high transport with 2 (4.8%). Discussion: In Central America during the last years there has been an increase in the incidence of kidney disease in workers from the Pacific coast, especially male farmers with no risk factors, thus constituting the epidemic of Mesoamerican nephropathy. There is a relationship between the increase in solutes transfer and the decrease of the ultrafiltration with the passage of time. Conclusions: Mesoamerican nephropathy is an emerging cause of disease in the region. No relationship was found between prolonged peritoneal dialysis time or the history of peritonitis with low peritoneal transport.

Effect of peritoneal dialysis on glycemic variability in patients with diabetes and its clinical implications / 中华临床营养杂志

Objective To compare glycemic profile between diabetic patients receiving peritoneal dialysis and diabetic patients with normal kidney function, and to investigate the impact of peritoneal dialysis on glycemic control through continuous glucose monitor system ( CGMS). Methods 19 diabetic patients with end-stage renal disease receiving regular peritoneal dialysis (DMPD group) and 8 patients with non-diabetic ne-phropathy receiving regular peritoneal dialysis ( PD group) were randomly selected and matched with 20 diabetic patients with normal kidney function (DM group) based on age, gender and 72 hours mean glucose. CGMS were applied on all patients for 72 hours. Glycemic variability parameters were compared among the three groups. Results Peritoneal transport function was positively correlated with mean glucose, glucose standard deviation and mean amplitude of glycemic excursion. Compared with PD group, multiple variation parameters, such as intraday glycemic standard deviation (P<0. 001), covariant efficiency (P=0. 009) and mean of daily difference (P=0. 043), were significantly lower in DMPD group. Though both DMPD and DM group exhibited profile as trough in wee hours and post-prandial hyperglycemia, DMPD had higher glycemic level in wee hours (P<0. 001). Conclusion Diabetic patients with end-stage renal disease receiving regular peritoneal dialysis have smaller glucose variability than diabetic patients with normal renal function.

Clinical characteristics and the factors relevant to peritoneal transport function in patients with continuous ambulatory peritoneal dialysis / 中南大学学报(医学版)

Objective:To observe the clinical characteristics with different peritoneal transport type in patients with continuous ambulatory peritoneal dialysis (CAPD),and to investigate the factors associated with peritoneal transport function.Methods:The clinical data of 158 CAPD patients were analyzed retrospectively.According to peritoneal equilibration test,a method for evaluation of the peritoneal transport function,the patients were divided into 2 groups:a high average and high peritoneal transport group (Group A,n=84) and a low average and low peritoneal transport group (Group B,n=74).T-he demographics,clinical biochemical indexes and the incidence of cardiovascular complications were compared between the 2 groups.Logistic regression analysis was used to find the factors relevant to peritoneal transport function.Results:The level of serum albumin (ALB) in the Group B was significantly higher than that in the Group A (P＜0.05).The 4 h dialysate/plasma creatinine (D/Pcr),high-sensitivity C-reactive protein (hs-CRP),body mass index (BMI),and the rates of cardiovascular complications in the Group A were significantly higher than those in the Group B (P＜0.05).Correlation analysis showed that the D/Pcr was positively correlated with the BMI,serum hs-CRP and cardiovascular complications (r=0.179,0.373 and 0.426,respectively,P＜0.05),while it was negatively correlated with ALB (r=-0.393,P＜0.01).Logistic regression analysis showed that the high BMI (OR=1.178,P＜0.05),cardiovascular complications (OR=5.035,P＜0.01),and the low serum ALB (OR=0.852,P＜0.01)were the risk factors for high peritoneal transport.Conclusion:The serum ALB level,BMI and the cardiovascular complications are associated with high peritoneal transport,which are useful markers for predicting the peritoneal transport function before peritoneal dialysis.

Impacts of baseline peritoneal transport characteristics and their changes during follow up on the survival of peritoneal dialysis patients / 中华肾脏病杂志

Objective To evaluate the effects of baseline and changes of peritoneal transport characteristics on the prognosis of maintaining peritoneal dialysis (PD) patients.Methods Five hundred and eight-six PD patients who started PD from September 11,2006 to October 30,2014 in a single center were included and followed up until March 30,2016.According to their baseline D/Pcr value in peritoneal equilibrium test (PET),the patients were divided into high transport (H) group (D/ Pcr 0.82-1.03),high average transport (HA) group (D/Pcr 0.65-0.81),low average transport (LA) group (D/Pcr 0.50-0.64) and low transport (L) group (D/Pcr 0.34-0.49).According to the changes of follow-up D/Pcr comparing with baseline D/Pcr,the patients were also divided into ascending group,descending group and no-change group.The patient and technical survival rates were estimated by Kaplan-Meier analysis.Cox proportional hazards analyses were used to analyze the risk factors for PD patient death and technical failure.Results There were 67 patients in L group,229 patients in LA group,252 patients in HA group,and 38 patients in H group.The patient survival rate in H group was significantly lower than those of L group (P=0.036),LA group (P=0.008) and HA group (P=0.041).There was no significant difference on technical survival rate among these 4 groups.According to the tendency of follow-up D/Pcr changes,there were 127 patients in ascending group,101 patients in descending group and 179 patients in no-change group.There was no significant difference on patient survival among these 3 groups (P=0.064).However in patients with a high transport rate (D/Pcr≥0.65),the patient survival was lower in descending group than those in ascending group (P=0.033) and nochange group (P=0.049).Age over 65 years old (HR=2.499),malnutrition during follow-up (HR=3.144),ultrafiltration less than 400 ml/d during follow-up (HR=1.863) and high sensitive C reactive protein≥ 10 mg/L (HR=4.526) were the independent risk factors for patient death (all P ＜ 0.05).Gender (HR=1.609),age over 65 years old (HR=1.929),ultrafiltration less than 400 ml/d during follow-up (HR=1.708),high sensitive C reactive protein ≥10 mg/L (HR=1.829),malnutrition (HR=1.876) and change of peritoneal transport function (HR=0.579) affect technical failure (all P ＜ 0.05).Conclusions The survival rate of PD patients with basal high peritoneal transit is relatively low,especially for patients with descending transport rate during follow-up.The concern on the peritoneal transport status is constructive for the prognosis of PD patients.

Effect of diabetes and peritoneal transport characteristic on the cardiac structure and function of patients with continuous ambulatory peritoneal dialysis / 中国综合临床

Objective To compare the cardiac structure and function between diabetic and non-diabetic with different peritoneal transport type.Methods A total of 84 patients with continuous ambulatory peritoneal dialysis (CAPD) in our center for 6 months were enrolled in this study.Forty-six patients of subjects were diabetic,another 38 were non-diabetic.Patients were divided into four groups according to the results of peritoneal equilibration test (PET) and the ratio of creatinine concentration in dialysate solution and plasma (D/P creatinine concentration).Patients with D/P creatinine concentration ＞ 0.65 were with high permeability and otherwise were low permeability.The four groups were diabetic-H (high permeability) group,diabetic-L(low permeability) group,non-diabetic-H (high permeability) group,non-diabetic-L (low permeability) group.The levels of left atrial diameter (LAD),left ventricular diameter(LVD),interventricular septal thickness(IVST),left ventricular posterior wall thickness(LVPWT),left ventricular ejection fraction(LVEF) were measured before and after 6-month peritoneal dialysis by ultrasonic doppler.Results Before peritoneal dialysis,there were no significant difference in the terms of all parameters among four groups(P ＞0.05).After 6 months of peritoneal dialysis,the albumin levels,IVST,LVPWT and LVEF in diabetic-L group,non-diabetic-L,diabetic-H group and non-diabetic-H group were ((36.57 ± 3.34),(37.21 ± 4.12),(34.19 ± 3.98),(34.51 ± 4.52) g/L respectively;F =9.034),((10.45 ± 1.12),(10.17 ± 1.35),(11.32 ± 1.09),(11.46 ± 1.38) mm respectively;F =7.525),((9.58 ± 1.42),(9.47 ± 1.31),(10.71 ± 1.40),(10.15 ± 1.41) mm respectively; F =4.963) and ((63.98 ± 4.73) ％,(63.92 ± 5.17) ％,(60.12 ± 5.12) ％,(61.43 ± 5.57) ％respectively ;F =6.984),and the differences were statistic significant (P ＜ 0.05).Compared to diabetic-H group and non-diabetic-H group,there were significant difference in the terms of all above indexes between diabetic-L group,non-diabetic-L (P ＜ O.05).Conclusion The peritoneal transport.type of diabetic patients is high permeability,which might be an important factor affecting cardiac complications in patients.

Relationship between peritoneal transport type and serum C-reactive protein in maintenance peritoneal dialysis patients / 中国医师进修杂志

Objective To evaluate the relationship between peritoneal transport type and serum C-reactive protein (CRP) in maintenance peritoneal dialysis (MPD) patients.Methods Standard peritoneal equilibration test (PET) was performed in 56 MPD patients (MPD group) with regular follow-up.According to D/P values,56 patients were divided into high permeability group (D/P ＞ 0.65,18 cases) and low permeability group (D/P ≤ 0.65,38 cases).In parallel at the date of PET examination,serum creatinine,blood urea nitrogen,uric acid,CRP and dialysate creatinine,blood urea nitrogen,uric acid was tested with an automatic biochemical analyzer,and urea clearance index and creatinine clearance rate was calculated.Dialysis prescription was formulated according to PET results to reach the criteria urea clearance index ≥ 1.7 and creatinine clearance rate ≥ 50 L/(week· 1.73 m2).Six months after MPD treatment,these indexes were detected again.And 20 cases of healthy person (control group) and 30 cases of uremic non-dialysis patients (uremic non-dialysis group) were selected randomly.Results The serum CRP level in high permeability group,low permeability group,uremic non-dialysis group was higher than that in control group [(54.41 ± 17.77),(43.34 ± 18.07),(39.10 ± 17.86) mg/L vs.(2.00 ±0.36) mg/L,P＜ 0.05].The serum CRP level in high permeability group was higher than that in low permeability group (P ＜ 0.05).There was no significant difference in the serum CRP level between MPD group and uremic non-dialysis group (P ＞0.05).There was no significant difference in the serum CRP level between 6 months after MPD and the date of the PET examination in high permeability group,low permeability group (P ＞ 0.05).Six patients with low permeability peritoneal transport changed into the high permeability at 6 months after MPD.The serum CRP level in these 6 patients at 1 month after catheter were significantly higher than the other patients of the low permeability [(64.45 ± 13.05) mg/L vs.(39.38 ± 16.12) mg/L,P ＜ 0.05].Conclusions Uremic patients in vivo exist micro-inflammatory state.The peritoneal transport characteristics of MPD patients are mainly in low permeability.Peritoneal transport characteristics of high permeability in vivo in patients with existing micro-inflammatory status are more severe than those in patients with low permeability.MPD treatment can not change the serum CRP levels in uremic patients.The original micro-inflammatory state in uremic patients may affect their peritoneal transport type.

The effects of angiotensin-converting enzyme inhibitors on peritoneal protein loss and solute transport in peritoneal dialysis patients

OBJECTIVE: The objective of this study was to examine the effects of angiotensin-converting enzyme inhibitors on peritoneal membrane transport, peritoneal protein loss, and proteinuria in peritoneal dialysis patients. METHODS: Fifty-four peritoneal dialysis patients were included in the study. The patients were divided into two groups. Group 1 (n = 34) was treated with angiotensin-converting enzyme inhibitors. Group 2 (n = 20) did not receive any antihypertensive drugs during the entire follow-up. Eleven patients were excluded from the study thereafter. Thus, a total of 30 patients in Group 1 and 13 patients in Group 2 completed the study. We observed the patients for six months. Group 1 patients received maximal doses of angiotensin-converting enzyme inhibitors for six months. Parameters at the beginning of study and at the end of six months were evaluated. RESULTS: At the end of six months, total peritoneal protein loss in 24-hour dialysate effluent was significantly decreased in Group 1, whereas it was increased in Group 2. Compared to the baseline level, peritoneal albumin loss in 24-hour dialysate effluent and 4-hour D/P creatinine were significantly increased in Group 2 but were not significantly changed in Group 1. A covariance analysis between the groups revealed a significant difference only in the decreased amount of total protein loss in 24-hour dialysate. Proteinuria was decreased significantly in Group 1. CONCLUSION: This study suggests that angiotensin-converting enzyme inhibitors reduce peritoneal protein loss and small-solute transport and effectively protect peritoneal membrane transport in peritoneal dialysis patients.

The influence of peritoneal transport characteristics on the nutritional status of patients with continuous ambulatory peritoneal dialysis / 中国医师进修杂志

ObjectiveTo explore the influence of peritoneal transport characteristics on the nutritional status of patients with continuous ambulatory peritoneal dialysis(CAPD).MethodsSeventy-three CAPD patients were involved in this cross-sectional study.According to the results of peritoneal equilibration test(PET),the patients were divided into high transport group with 43 cases and low transport group with 30 cases.Nutritional status was evaluated with the subjective global assessment (SGA) score and the differences were analyzed between two groups in the albumin (ALB),total protein (TP),hemoglobin (Hb),primary disease,age,weight,dialysis time,ultrafiltration,blood urea nitrogen ( BUN ),serum creatinine (SCr) and so on.Results There was no difference between two groups in age,weight,ultrafiltration,systolic blood pressure,diastolic blood pressure,Hb,SGA score,BUN and SCr (P＞0.05).However,the dialysis time,the case number of diabetic nephropathy (DN) as original disease,the case number of non DN as original disease,TP and ALB between high transport group and low transport group had significant differences [(14.35±13.88) months vs.(24.20 ±19.62) months,16 cases vs.12 cases,27 cases vs.18 cases,( 64.98±7.59 ) g/L vs.( 68.73 ± 6.96 ) g/L,( 34.61 ± 5.43) g/L vs.( 38.71±3.82 ) g/L,P ＜ 0.05 ].Conclusions The nutritional status of CAPD patients with different transport characteristics have significant differences.CAPD patients with high transport characteristics are complicated with worse nutritional status,compared with those patients with low transport characteristics.

Great influence of peritoneal transport characteristics on ultrafiltration of icodextrin / 中华肾脏病杂志

Objective To observe the long dwell ultrafiltration volume after using 7.5% icodextrin in different peritoneal transport characteristics of peritoneal dialysis patients. Methods Subgroup analysis of a perspective multicenter randomized double blind and parallel control study was performed. Continuous ambulatory peritoneal dialysis (CAPD) patients were divided into high transport (H) group, high-average transport (HA) group, low-average transport (LA) group and low transport (L) group according to D/Pcr and Twardoski standard. Ultrafiltration volume of night long dwell dialysate was calculated before and after clinic trial for 2 weeks and 4 weeks to evaluate the different effect of transporters on ultrafiltration volume. Results A total of 201 CAPD patients were enrolled in the study, including 98 patients in icodextrin group (ICO group) and 103 patients in glucose group (GLU group). Male and female cases were 96 and 105 respectively. Age was (56.1±13.7) years old (range from 18 to 81). One hundred and ninety-eight patients finished peritoneal equilibrium test (PET), including 24 (12.1%) of H, 72(36.2%)of HA, 81(40.7%)of LA,and 21 (11.0%)of L. After follow-up for four weeks, the ultrafiltration volume was much higher than baseline in H, HA and LA groups. Also ultrafiltration volume in icodextrin group was much higher than that in glucose-based dialysate. Howerve, the increased volume was not significantly difference in L group. Ultrafiltration volume of icodextrin was positively correlated to D/Pcr (R2=0.1681,P＜0.01), while ultratration volume of dextrose was negatively correlated to D/Pcr (R2=0.0949,P＜0.01). Conclusion Compare to glucose-based dialysate (Dineal), 7.5% icodextrin dialysate (Extraneal) improves the ultrafiltration and peritoneal creatinine clearance of long dwell notabily in H, HA and LA group.

Role of peritoneal transport characteristics and nutritional status in evaluation of peritoneal dialysis adequacy / 中华临床营养杂志

Objective To evaluate the influence of peritoneal transport characteristics on nutritional status of peritoneal dialysis patients and estimate the role of peritoneal transport characteristics and nutritional status in evaluation of peritoneal dialysis adequacy. Methods Peritoneal transport properties (D/Pcr) were evaluated by Short Peritoneal Equilibration Test and then 53 cases were divided into high transport group (D/Pcr ≥0. 65) and low transport group (D/Pcr < 0. 65). Urea kinetics (Kt/v) and total clearance of creatinine (TCcr) were calcu- lated. Serum albumin (ALB), prealbumin, transferring (TF), hemoglobin (Hb), lean body mass (LBM) and LBM% were examined or calculated. Subjective global assessment (SGA) was used to evaluate the nutritional sta- tus of patients. Results There were 30 cases in high transport group and 23 cases in low transport group. D/Pcr (0. 82±0.15 vs. 0. 55±0. 08, P < 0. 01), TCcr (62. 93%±25. 98% vs. 49. 69%±16. 92% , P < 0. 05) and age were significantly higher in high transport group than those in low transport group, while ALB, TF, Hb, LBM% , and SGA were significantly lower than those in low transport group (P < 0.05). ALB was negatively cor-related with Kt/v (r= -0.2708, P<0. 05). Conclusions High peritoneal transport patients have better solute clearance but worse nourishment status compared with low transport ones. Nutritional status is one of the factors to evaluate dialysis adequacy. Nutrition management and guidance should be strengthened for the continuous ambula- tory peritoneal dialysis patients, especially for the elderly ones.

Evaluation of inflammation and oxidative stress in uremic patients on peritoneal dialysis(PD)with different peritoneal transport status / 中国实用内科杂志

0.05).Conclusion Peritoneal dialysis may lead to lower inflammatory and oxidative stress state than the non-dialysis uremic.HPD patients may be in higher oxidative stress and inflammatory state than LPD patients.

Effects of Peritoneal Rest on Peritoneal Fibrosis in CAPD Rats / 대한신장학회잡지

Ultrafiltration failure has been known as a major cause of dropout from long-term peritoneal dialysis and is often related to peritoneal hyperpermeability. This can be explained in part by progressive peritoneal fibrosis. The present experiment has been undertaken to evaluate the effects of peritoneal rest on peritoneal transport and morphology in rat model of peritoneal dialysis. Twenty-four male rats(Sprague-Dawley, 250-300g) were used and divided into three groups : group 1 (control, n=6) without dialysis, group 2(n=9) sacrificed immediately after 3 weeks of dialysis, and group 3 (n=9) sacrificed after 4 weeks of peritoneal rest after 3 weeks of dialysis. Peritoneal dialysis was performed twice a day with 25mL of 3.86% dextrose solution for 3 weeks. Peritonitis was induced by supplementing lipopolysaccharide(5 microgram/mL) in the dialysis fluid on days 8, 10 and 12 of peritoneal dialysis. Peritoneal equilibration tests were performed before dialysis and repeated on the 4th and 8th week of dialysis. Morphometric analysis of the peritoneal membrane and immunohistochemistry for collagen type I and type III were done in tissue specimens obtained at the time of sacrifice. The D/Do ratio for glucose at two hours in groups 2 and 3 at the beginning of week 4 were significantly lower than baseline value, indicating increase in the peritoneal penneability to glucose after 3 weeks of dialysis. D/Do in group 3 at the beginning of week 8, after 4 weeks of peritoneal rest, was significantly higher than at week 4. The drained dialysate volumes in groups 2 and 3 at week 4 were significantly lower than at baseline; however, The drained dialysate volume in group 3 at week 8 was significantly greater than at week 4. The thickness of the parietal peritoneal membraoe in group 2 and 3 were significantly greater than in group 1. Severity of the thickness of the parietal peritoneal membrane in group 3 was not much than that of group 2(group 1, 11.4+/-7.6; group 2, 37.5+/-18.4; group 3, 21.4+/-12.1 micromiter). Histologically, the thickened peritoneum in group 2 showed a monolayer of mesothelial cells and under-lying multilayer of curled collagen bundles. Mononuciear cells and fibroblasts were embedded in these collagen layers and capillary proliferation was present. Immunohistochemistry for collagen type I and Z demonstrated that the distribution of collagen type llI was richer than that of collagen l in group 2 at fibrotic area of submesothelial region. These findings were decreased in group 3. Ultrastructural examination of the peritoneum showed thicker fibrotic zone and the activated fibroblasts in group 2 compared to group 1 and 3. Meso-thelial cells were plump and the number of mesothelial microvilli was decreased in group 2. Nucleus was enlarged and irregular. Intracytoplasmic orga-nelles were also richer than those of group I or 3. In conclusion, peritoneal rest improves ultrafiltration in rats by decreasing the hyperpermeability of glucose and also reduces the degree of peritoneal fibrosis. These data suggest that dialysis-induced changes in peritoneal transport and morphology are reversible under the condition of peritoneal rest in this experimental model.

Acid-base Balance of Korean CAPD Patients: Incidence of Metabolic Acidosis and Factors Affecting the Acid-base Status / 대한신장학회잡지

OBJECTIVES: Any form of dialysis must provide a sufficient replenishment of buffer. Lactate with a con- centration of 35 to 40mM/L is now the only buffer routinely used in CAPD. Buffer balance using lactate solutions will be governed essentially by the balance between the H+ generated, the amount of bicarbonate lost into the peritoneal effluent, and the lactate absorbed from the dialysate. Factors affecting buffer balance in CAPD patients will therefore include dietary protein intake which determine H+ generation and ultrafiltration which can affect bicarbonate loss. Although several studies reported a different prevalence of metabolic acidosis in their CAPD patients, it is uncertain whether the same prevalence of metabolic acidosis(MA) or the similar characteristics of acid-base status of Western CAPD patients can be found in Asian patients with smaller body size and relatively less amount of dietary animal protein intake. This study was undertaken to know the current acid-base status of CAPD patients in Korea with the exact information about buffer balance. We will also investigate the factors affecting acid-base homeostasis in CAPD patients such as dietary protein intake, the individual membrane characteristics and the various indices of dialysis adequacy and nutritional status of patients. METHODS: The acid-base status of Korean CAPD patients was assessed based on arterial blood gas analysis along with various nutritional parameters including subjective global assessment(SGA), anthropometric measurements and standard peritoneal equilibration test in 198 clinically stable patients main- tained on CAPD for more than 6 months using 35- 40mM/L of lactate-based dialysate(M:F 106:92, mean age 47.9 years, mean duration 45.3 months). RESULTS: Mean arterial bicarbonate concentration was 24.6+/-3.4mM/L with a range of 16.2-36.7mM/L and mean dialytic base gain was 29.4+/-15.2mM/day. Only 28(14.1%) patients showed MA while 52(26.3%) patients had a various degree of metabolic alkalosis. Normal acid-base status was observed in 75 patients(37.9%). The rest showed mixed acid-base abnormalities of respiratory origin. Patients with MA (mean HCO3 19.5+/-1.9mM/L) showed significantly higher serum albumin(4.01+/-0.38 vs. 3.59+/-0.46 g/dl, P<0.001) & protein equivalent of nitrogen appearance (NPNA, 1.2+/-0.1 vs. 0.9+/-0.2 g/kg/day, P<0.05) compared to the metabolic alkalosis group(mean HCO3 28.1+/-1.9mM/L). Dialytic protein loss(6.39+/-1.86 vs. 7.64+/-2.71 g/day, P<0.01) and D/PCr(0.60+/-0.09 vs. 0.71+/-0.13, P<0.05) were significantly lower in MA group. There were no significant differences in residual renal function, KT/VUrea, number of malnourished patients by SGA and other anthropometric parameters according to the acid-base status of patients. There were significant inverse correlations of arterial HCO3 with serum albumin and NPNA while HCO3 was positively correlated with duration of dialysis, ultrafiltration volume, dialytic lactate gain and dialytic protein loss. CONCLUSION: Our results on the acid-base status of Korean CAPD patients including a generally lower incidence of MA appear to be quite different from other reports based on the Western population. The peritoneal membrane transport characteristics can be one of the important factors determining the acid- base status of peritoneal dialysis patients. Duration of dialysis and protein catabolic rate also influence arterial bicarbonate level independently.

Nutritional Status of Long-term CAPD Patients-Impact of Peritoneal Transport Characteristics / 대한신장학회잡지

Protein-calorie malnutrition is common in CAPD patients and is associated with increase in morbidity and mortality in CAPD patients. There are many causes of malnutrition in CAPD patients, and it is well known that a large amount of protein losses through peritoneal membrane is one of them. To investigate the effect of the peritoneal membrane transport characteristics on the nutritional status in long-term CAPD patients, we conducted a cross- sectional study on clinically stable 115 patients (63 males and 52 females) who have been on CAPD for more than 2 years, and assessed nutritional status by subjective global assessment (SGA), biochemical, anthropometric and urea kinetic parameters. Patients were divided into 4 groups according to the results of standard peritoneal equilibration test (PET). The results were as follows: 1) The patients were divided into 4 groups according to the PET results: high transporter (n=16, 14%), high average transporter (n=38, 33%), low average transporter (n=50, 43%), and low transporter (n=11, 10%). 2) The mean age of the patients was 50.1+/-11.6 years (range, 19-75) with sex ratio (M:F) 1.2:1 and mean duration of dialysis was 57.5+/-27.8 months (range, 24-135). The mean body weight (Bwt) was 59.2+/-8.9kg, percent ideal body weight (%IBW) was 104.7+/-15.6%, %lean body mass (LBM)/Bwt was 82.1+/-11.1%, and malnourished patients by subjective global assessment (SGA) were 32.2% (38/115). 3) The mean BUN, creatinine, total protein, and albumin level of the patients were 54.5+/-13.1mg/dL, 12.3+/-3.0mg/dL, 6.7+/-0.8g/dL, and 3.8+/-0.6g/dL, respectively. 4) There were no significant differences in age, sex ratio, CAPD duration, peritonitis rate, %LBM/ Bwt, and SGA among the 4 groups. 5) Total protein (g/dL) and albumin (g/dL) levels in high transporters were 6.4+/-0.5, 3.5+/-0.4, respectively, and they were significantly lower than those of low transporters (7.2+/-0.6, 4.2+/-0.5) (P<0.05). 6) 24 hour dialysate protein (g/day) and albumin (g/day) losses were significantly higher in high transporters (8.10+/-1.85, 4.19+/-1.23) compared to those of low transporters (5.07+/-1.85, 2.78+/-0.99) (P<0.05). 7) The level of IGF-1 (ng/mL) was significantly lower in high transporters (150.5+/-86.2) compared to that of low transporters (310.3+/-162.1) (P<0.05). 8) The level of BUN (mg/dL), Cr (mg/dL) were also lower in high transporters (45.4+/-13.1, 10.1+/-2.0) than those of low transporters (61.6+/-18, 14.7+/-2.7), but there were no significant differences in Hct, total cholesterol, prealbumin, and transferrin among the 4 groups. 9) There were no statistically significant differences in Kt/Vurea, RRF, NPCR, dietary calorie and protein intakes among the 4 groups. 10) Anthrometric parameters such as TSF, BSF, MAC and LBM measured by three different methods (LBMCr, LBMimp, LBManthro) didn't show any significant differences among the 4 groups. In conclusion, increased peritoneal permeability may not adversely affect SGA and anthropometric status of long-term CAPD patients, although it is associated with lower serum albumin, creatinine, and IGF-1 level. Clinical significance of these findings remains to be elucidated.