Can sonographic peritoneal thickness be used to follow pediatric patients on peritoneal dialysis?

Background

Peritoneal dialysis (PD) is an effective and successful therapy for end-stage renal disease (ESRD). However, PD does not have a life-long effectiveness, and peritoneal membrane failure is commonly observed in long-term PD patients. We hypothesized that ultrasonography could be used to follow these patients.

Methods

We recruited two patient groups (age range 3–18 years), of whom 20 had ESRD with ongoing PD for ≥24 months (study group) and 20 were pre-dialysis non-ESRD patients (control group). None of the patients had peritonitis during the preceding 3 months, and none had a history of abdominal surgery or malignancy. We measured the sonographic thickness of the parietal peritoneum and obtained Doppler indices of the superior mesenteric artery (SMA) by trans-abdominal ultrasonography.

Results

Peritoneal thickness as determined by sonography was significantly greater in the PD group than in the controls. The correlation between duration of PD and thickness of the peritoneal membrane was linear and statistically significant. We categorized all 20 patients as either rapid transporters or slow transporters for both creatinine and glucose. The peritoneal membranes of patients who were rapid transporters for both creatinine and glucose were significantly thicker than those of the slow transporters. No statistical difference was found between the Doppler indices of the SMA between the groups.

Conclusion

Thickness of the parietal peritoneum as determined by sonography is associated with PD duration and transport characteristics. We conclude that ultrasonography is a non-invasive and practical method which can be useful for following PD patients.     

Can the National Kidney Foundation guidelines for first-time arteriovenous fistula creation be met in underserved end-stage renal disease patients?

The aims of this study were to determine whether National Kidney Foundation (NKF) guidelines for native arteriovenous fistula (AVF) creation (at least 50% of all new end-stage renal disease [ESRD] patients and 40% of prevalent hemodialysis patients) could be met in an underserved population who presented in late stages of ESRD. We also sought to determine 1-year AVF patency rates and factors associated with early thrombosis. One hundred seventy-six patients underwent hemodialysis access surgery during the period 2003-2005 with a mean age of 51 years. Sixty-two percent were male, and 48% had diabetes mellitus. Ultrasound vein mapping was performed in only 37%. Temporary central venous access was necessary in 109 patients (62%) due to late presentation. Of the 160 patients who were first-time access, 137 (86%) received a native AVF and 23 (14%) had an arteriovenous graft. There was a higher rate of AVF creation in males (91% vs. 75% for females, p = 0.005). The 1-year primary patency was 90%. There were no differences in early thrombosis or 1-year patency rates with respect to gender, age, ethnicity, insurance status, presence of temporary access, or use of preoperative vein mapping. In an underserved population, NKF guidelines for native AVF for first-time access can be superseded with an excellent 1-year patency, despite late presentation.     

Can acute appendicitis be treated by antibiotics alone?

Emergency appendectomy at presentation has been the standard of care for acute appendicitis. We examined the use of antibiotics as an alternative treatment. From September 2002 to August 2003, 170 consecutive patients diagnosed with acute appendicitis without abscess were reviewed retrospectively. Patients were divided into two groups: Group I (n=151) underwent emergency appendectomy and Group II (n=19) received antibiotics alone. The mode of treatment was at the attending surgeon's discretion. The overall complication rate was eight per cent for Group I and 10 per cent for Group II patients (P = 0.22). Group II patients suffered no complications during antibiotic treatment, and any complications that did occur developed after subsequent appendectomy. One Group II patient had recurrent appendicitis (5%). The length of stay was 2.61 +/- 0.21 days for Group I and 2.95 +/- 0.38 days for Group II patients (P = 0.57). Patients with acute appendicitis may be treated safely with antibiotics alone without emergency appendectomy.     

Can biliary atresia be diagnosed by ultrasonography alone?

Background/Purpose

The triangular cord sign (TCS) is a specific ultrasonographic finding, reflecting a fibrotic mass at the porta hepatis in biliary atresia (BA). We evaluated whether BA can be diagnosed by ultrasonography alone using 3 findings: TCS, gallbladder length (GBL), and gallbladder contractility (GBC).

Methods

Subjects comprised 85 infants (median age, 47 days; range, 4-144 days) with cholestatic jaundice who underwent ultrasonographic examination for diagnosis between May 1996 and June 2006. Medical records were reviewed with regard to TCS, GBL, and GBC. Positive findings for BA included TCS ≥3 mm, GBL <15 mm, and GBC <68% (for < 12 weeks) or <25% (for ≥12 weeks).

Results

Biliary atresia was diagnosed in 48 patients surgically, with other cholestatic diseases diagnosed in the remaining 37 patients. Triangular cord sign was positive in 41 of 48 infants with BA and negative in 35 of 37 infants without BA. The 7 patients with BA who displayed negative results for TCS displayed positive findings for GBL or GBC. Positive predictive value in the diagnosis of BA was 98% if positive TCS was combined with abnormal gallbladder findings, whereas negative predictive value in diagnosis of BA was 100% if negative TCS was combined with findings of a normal gallbladder.

Conclusions

Biliary atresia can be accurately diagnosed by ultrasonography using the findings of TCS combined with GBL and GBC.     

How can videolaparoscopy be used in a peritoneal dialysis programme?

BACKGROUND: Recently videolaparoscopy is considered to have a vaster use in surgery due to the undeniable benefits such as low operatory traumatism, quick recovery of canalization, a short stay in the hospital and minor scarring. METHODS: Forty patients were treated with peritoneal dialysis (PD); 15 videolaparoscopic procedures were performed on 13 patients before starting PD and two during the course of PD. The videolaparoscopy procedure was started by inducing pneumoperitoneum after initiation of general anaesthesia through endotracheal intubation. RESULTS: Peritoneal catheter placement was carried out in 11 ESRD patients showing abdominal scars due to previous laparotomies; their abdominal condition precluded safe PC placement using conventional non-laparoscopic procedures with local anaesthesia. Release of adhesions was performed only in two patients. Videolaparoscopy was also used in three patients for elective cholecystectomy; 2/3 underwent concomitant PC insertion. One patient was submitted to cholecystectomy during the course of CAPD; following the procedure we left the peritoneum dry overnight and then we started temporary IPD, using small volumes, avoiding haemodialysis (HD). Regular CAPD was resumed 6 days later. Finally, videolaparoscopy was also used for diagnostic purpose i.e. in one 59-year-old man patient who had a peritoneal catheter obstruction. Repeated rescue attempts using urokinase solution to irrigate the peritoneal catheter had been used in vain attempts prior to the procedure. CONCLUSIONS: Videolaparoscopy proves to be a useful tool in a PD programme. Firstly, it may be used as a technique for catheter implantation, not as a routine procedure but in patients with extensive abdominal scars due to previous laparotomy, i.e. at risk for accidental viscera perforation due to the possibility of adhesions between intestinal loops and parietal peritoneum. Secondly, videolaparoscopy used for abdominal surgery allows the resumption of PD immediately after surgical procedure and thus avoiding HD. Videolaparoscopy is fundamental for diagnosis and rescue of catheter dysfunction and has an integral role in the successful management of these patients in extending catheter function and permitting safe replacement of peritoneal catheter if it becomes necessary. Along with the undeniable advantages, remains the disadvantages that it must be carried out by an expert surgeon in an operating theatre while the patient is under general anaesthesia.     

Does low peritoneal glucose load protect from the development of left ventricular hypertrophy in peritoneal dialysis patients?

Background

Left ventricular hypertrophy (LVH) is a major predictor of the development of cardiovascular events that is considered the main cause of morbidity and mortality in peritoneal dialysis (PD) patients. This study aimed to evaluate retrospectively the impact of low peritoneal glucose load on left ventricular mass (LVM) in PD patients.

Methods

36 patients who were on continuous ambulatory PD for at least a period of 2 years enrolled in the study. Of them, 23 patients received only glucose-based solutions (GBS) [high peritoneal glucose load group (HPGL group)] from the start of PD, and 13 patients received AAS in combination with GBS when their serum albumin decreased to levels <3.5 g/dl [low peritoneal glucose load group (LPGL group)]. AAS was substituted with 1.36 % GBS when serum albumin rose to ≥3.5 g/dl and restarted when serum albumin fell to <3.5 g/dl. Medical history, physical findings, echocardiographic, laboratory and hydration status data from the first month of PD and after 24 months, were obtained from each patient’s medical records.

Results

Mean LVM index (LVMI) increased in both groups (p ≤ 0.010). The increment in mean LVMI was higher in HPGL group compared to LPGL group (p = 0.006). At 24 months: peritoneal glucose load index (PGLI), fluid overload, mean arterial pressure (MAP), HbA1c and hsCRP were higher in HPGL group (p ≤ 0.010), while 24 h ultrafiltration, weekly Kt/V, serum albumin levels and RRF were higher in LPGL group (p ≤ 0.025). The increment (Δ between the values of each parameter from the start of PD and after 24 months) in PGLI, fluid overload, MAP, HbA1c and hsCRP values were higher in HPGL group (p < 0.001).

Conclusions

Low peritoneal glucose load may be associated with a protective effect from the development of LVH in PD patients.

     

Should peritoneal dialysis catheters be removed at the time of kidney transplantation?

Background:

Delayed graft function (DGF) following transplantation necessitates support in the form of hemodialyis (HD) or peritoneal dialysis (PD). However, post-transplant PD-related complication and failure rates are unknown.

Methods:

We studies patients who were on PD at the time of kidney transplantation over a 4-year period at two separate institutions.

Results:

Of the 137 PD patients, 19 had their catheters removed at the time of transplant. Of the remaining 118 patients, 89% had immediate graft function. PD-related complications in this group included peritonitis (n=5), catheter-related infections (n=2) and emergency laparotomy (n=1). Of the 15 patients requiring post-transplant PD, 33% developed peritonitis and 20% had fluid-leaks necessitating HD. Overall, leaving a PD catheter in situ post- transplantation is associated with 7% rate of peritonitis versus 0% if removed (p < 0.05).

Conclusions:

PD catheter removal should be considered at the time of renal transplantation, as postoperative PD-related failure/complication rates are high.     

Medulloblastomas in adolescents and adults – Can the pediatric experience be extrapolated?

Adult medulloblastomas are orphan diseases that differ from their pediatric counterpart. Most are classified as classic or desmoplastic and fall in the SHH subgroup, mainly with loss-of-function mutations in PTCH1 and some by TP53-mutation due to underlying germline mutation. Activation of the WNT pathway is sporadic, although underlying Turcot syndrome may be present. One-third of tumors are issued from group 4. Most adult studies are small non-randomized retrospective heterogeneous studies performed at a single center with short follow-up. Standard craniospinal irradiation followed by maintenance chemotherapy (CCNU, cisplatin-vincristine) results in a 4-year event-free survival (EFS) and overall survival (OS) of 68% and 89% respectively in standard-risk adults, and in a 4-year EFS and OS of 50% and 90%, respectively in high-risk adults. Several pooled analyses point out the potential role of chemotherapy in adults. The feasibility of pediatric protocols in adults is sometimes hampered because of blood and peripheral nerve toxicity. In the near future, subgroups of medulloblastomas may be treated by personalized therapies. With prolonged follow-up, adults fare worse. Long-term sequelae and second line treatment are not well defined in adults. Prospective studies are ongoing to define optimal first-line and relapse treatments.     

Is C-reactive protein a useful predictor of outcome in peritoneal dialysis patients?

An elevated C-reactive protein (CRP) has recently been shown to be strongly predictive of mortality in hemodialysis patients. However, its predictive value in peritoneal dialysis (PD) patients has not been assessed. A cohort of 50 PD patients was followed prospectively for a 3-yr period, after initial determination of CRP. Patients with an elevated CRP (>6 mg/L; n = 29) had significantly reduced plasma prealbumin (0.36 +/- 0.02 versus 0.44 +/- 0.03 g/L; P: < 0.05), decreased total weekly creatinine clearance (C(Cr); 52.5 +/- 2.3 versus 63.1 +/- 3.2 L/1.73 m(2); P: < 0.01), and increased left ventricular thickness (1.24 +/- 0.05 versus 1.08 +/- 0.06 cm; P: < 0.05) at baseline compared with those who had a normal CRP (< or =6 mg/L; n = 21). Baseline CRP (log-transformed) correlated weakly with baseline Kt/V, C(Cr), and pre-albumin. With the use of a multivariate Cox's proportional hazards model to adjust for potential confounding factors, an elevated CRP was predictive of myocardial infarction (adjusted hazard ratio, 4.8; 95% confidence interval [CI], 1.0 to 23; P: = 0.048) and tended to be predictive of fatal myocardial infarction (adjusted hazard ratio, 6.0; 95% CI, 0.8 to 43; P: = 0.07). However, CRP was not significantly associated with all-cause mortality (adjusted hazard ratio, 2.1; 95% CI,0.8 to 5.4; P: = 0.15). In conclusion, CRP elevation occurs in a substantial proportion of PD patients and is independently predictive of future myocardial infarction. Such patients may warrant closer monitoring and attention to modifiable cardiovascular risk factors.     

The mini-PET in pediatric peritoneal dialysis: A useful tool to predict volume overload?

Background

Cardiovascular disease (CVD) in patients on chronic peritoneal dialysis (PD) is a major cause of death and is closely linked to hypertension and volume overload. The mini-Pet has been proposed as a useful tool to evaluate free-water transport (FWT) and characterize ultrafiltration across the peritoneum. Knowledge regarding FWT could be of great value to predict volume overload in PD patients. Our objective in this study was to characterize FWT through the peritoneum in children on PD.

Methods

We studied clinically stable patients with >2 months on PD. Exclusion criteria were a peritonitis episode up to 2 months prior to entrance into the study and active nephrotic syndrome. A 1-h mini-peritoneal equilibration test (mini-PET) was performed with 3.86 % glucose. Calculations (see text for full definitions) were: Dip Na (Na dial min₆₀ ? Na dial min₁), Dip D/PNa (D/PNa₆₀ ? D/PNa₁), total Na removal (Na_R = total Na dial₆₀ - Na dial₁), ultrafiltration small pores [(UFSP = Na_R × 1,000)/Na_p], and FWT (UF-UFSP). Peritoneal equilibration test (PET), left ventricular mass index (LVMI, g/m²), daily UF, and residual renal function were evaluated. Pearson’s correlation coefficient was used to establish correlation between variables.

Results

Sixteen patients were included, with a mean age of 11.8?±?3.8 years. Free water transport normalized to body surface area (BSA) (FWT_n) was 133.9?±?85.7 ml/m²; creatinine dialysate-to-plasma (D/P) and glucose dialysate at X dwell time-to-0 dwell time (D_x/D₀) ratios were 0.38?±?0.1 and 0.65?±?0.09, respectively. LVMI was 46.6?±?14.8 g/m²; 2-h creatinine D/P and glucose D_x/D₀ showed no correlation with FWT_n, UF, and LVMI. FWT_n showed a significant inverse correlation with LVMI (r 0.58, p 0.02).

Conclusions

This study characterized FWT in PD children through the mini-PET. Left ventricular hypertrophy showed a high prevalence in this group, and a significant correlation between LVMI and FWT was found. FWT could be a useful tool to evaluate UF in PD children.     

Improving wellbeing in patients undergoing dialysis: Can meditation help?

Coping with the stress and anxiety caused by end stage kidney disease (ESKD ) symptoms, treatment, restrictions, and social, financial and family stressors, consumes many afflicted with kidney disease. Meditation has been shown to decrease anxiety and stress, and improve wellbeing and quality of life of people with chronic disease. However, the clinical uptake of meditation is low in the ESKD dialysis population. This review describes what meditation and mindful meditation are and how they have been used for people with ESKD . Further research, using active control conditions and larger sample size, is required to identify effective meditation interventions that can improve the wellbeing of our patients and their ability to cope with the demands of ESKD .     

Can peritoneal dialysis be used as a long term therapy for end stage renal disease?

Over the last 25 years, since the introduction of CAPD, the use of PD has increased greatly and over this period many advances in technique have been made. As is well known, that home and self-dialysis, such as PD, cost less than in-center HD and can provide excellent survival and a high level of patient rehabilitation. To date however, the demonstration that PD can provide long term dialysis has been limited to a small number of patients. The next few decades will see a marked increase in the worldwide dialysis population, particularly as older and sicker patients are accepted into dialysis. It is likely that worldwide pressures related to cost containment will favour the use of cost effective therapies, such as PD. However, the increased use of PD will continue, only if we continue to improve its efficacy and do not waste the economic benefits gained over HD. We are challenged to improve and develop PD in a way that optimises patient medical and psychosocial outcomes while minimizing costs. This may be achieved by using more biocompatible solutions, hopefully inexpensive, that will maintain the peritoneal membrane intact for long periods, will better preserve the membrane's transport characteristics over time, and thus reduce the main causes of drop out from dialysis.