Febrile Urinary Tract Infections in Children: The Role of High Mobility Group Box-1

BACKGROUND

Differentiating between febrile lower urinary tract infection (LUTI) and acute pyelonephritis (APN) is crucial for prompt clinical management. We investigated whether the high mobility group box-1 (HMGB1) could be a useful biomarker in differentiating between LUTI or APN.

METHODS

We enrolled seventy-four pediatric patients with suspected LUTI/APN, according to the positive or negative renal scintigraphy (DMSA) scan. If the first DMSA findings were abnormal, a second DMSA was performed after six months. Voiding cystourethrography ruled out vesicoureteral reflux (VUR).

RESULTS

Higher serum (s) HMGB1 levels characterized the APN group when compared to LUTI patients (13.3 (11.8-14.3) versus 5.9 (5.2-6.8) ng/mL, p: 0.02), whereas there were no differences according to urine (u) HMGB1 values. sHMGB1 correlated with C-reactive protein (CRP) levels (β = 0.47; p: 0.02). Receiver operating characteristic curves identified the best diagnostic profile for detecting APN. sHMGB1 area under the curve was different from CRP (p: 0.01) and white blood cells (p: 0.003). After multivariate analyses, VUR (HR:4.81) and sHMGB1 (HR 1.16; p: 0.006) were independently associated with the risk of renal scarring development.

CONCLUSIONS

sHMGB1 could represent a marker to differentiate APN from LUTI. Measurement of sHMGB1 could select children for early intervention or long-term follow-up.

Encapsulating peritoneal sclerosis: Your questions answered

Encapsulating peritoneal sclerosis (EPS) is a clinical syndrome hallmarked by the formation of a fibrous cocoon encapsulating the bowel resulting in morbidity and mortality. EPS is most frequently associated with peritoneal dialysis (PD), particularly with its discontinuation. While EPS is one of the most feared complications of PD, the majority of patients receiving PD will not go on to develop EPS. Risk factors for development include time on PD, some types of peritonitis and discontinuation of PD. Owing to its rarity, much of the knowledge of EPS comes from case series and registries and treatments are extrapolated from low-quality evidence. Malnutrition is a significant driver of mortality, and nutritional support is critical in management. We present a case of EPS and frequently asked questions including the definition, diagnosis, epidemiology, pathophysiology, risk factors, role of infection, management and roles of nutrition and surgery.

Surgical management of Encapsulating Peritoneal Sclerosis (EPS) in children: international case series and literature review

BACKGROUND

Encapsulating Peritoneal Sclerosis (EPS) is a rare phenomenon in paediatric patients with kidney failure treated with peritoneal dialysis (PD). This study highlights clinical challenges in the management of EPS, with particular emphasis on peri-operative considerations and surgical technique.

METHODS

Retrospective analysis of all paediatric patients with EPS treated at the Manchester Centre for Transplantation.

RESULTS

Four patients were included with a median duration of 78 months on PD. All patients had recurrent peritonitis (> 3 episodes), and all had symptoms within three months of a change of dialysis modality from PD to haemodialysis or transplant. In Manchester, care was delivered by a multi-disciplinary team, including surgeons delivering the adult EPS surgical service with a particular focus on nutritional optimisation, sepsis control, and wound management. The surgery involved laparotomy, lavage, and enterolysis of the small bowel + / - stoma formation, depending on intra-abdominal contamination. Two patients had a formal stoma, which were reversed at three and six months, respectively. Two patients underwent primary closure of the abdomen, whereas two patients had re-look procedures at 48 h with secondary closure. One patient had a post-operative wound infection, which was managed medically. One patient's stoma became detached, leading to an intra-abdominal collection requiring re-laparotomy. The median length of stay was 25 days, and patients were discharged once enteral feeding was established. All patients remained free of recurrence with normal gut function and currently two out of four have functioning transplants.

CONCLUSIONS

This series demonstrates 100% survival and parenteral feed independence following EPS surgery. Post-operative morbidity was common; however, with individualised experience-based decision-making and relevant additional interventions, patients made full recoveries. Health and development post-surgery continued, allowing the potential for transplantation. A higher resolution version of the Graphical abstract is available as Supplementary information.

Proteomic profile of mesothelial exosomes isolated from peritoneal dialysis effluent of children with focal segmental glomerulosclerosis

Peritoneal dialysis (PD) is the worldwide recognized preferred dialysis treatment for children affected by end-stage kidney disease (ESKD). However, due to the unphysiological composition of PD fluids, the peritoneal membrane (PM) of these patients may undergo structural and functional alterations, which may cause fibrosis. Several factors may accelerate this process and primary kidney disease may have a causative role. In particular, patients affected by steroid resistant primary focal segmental glomerulosclerosis, a rare glomerular disease leading to nephrotic syndrome and ESKD, seem more prone to develop peritoneal fibrosis. The mechanism causing this predisposition is still unrecognized. To better define this condition, we carried out, for the first time, a new comprehensive comparative proteomic mass spectrometry analysis of mesothelial exosomes from peritoneal dialysis effluent (PDE) of 6 pediatric patients with focal segmental glomerular sclerosis (FSGS) versus 6 patients affected by other primary renal diseases (No FSGS). Our omic study demonstrated that, despite the high overlap in the protein milieu between the two study groups, machine learning allowed to identify a core list of 40 proteins, with ANXA13 as most promising potential biomarker, to distinguish, in our patient population, peritoneal dialysis effluent exosomes of FSGS from No FSGS patients (with 100% accuracy). Additionally, the Weight Gene Co-expression Network Analysis algorithm identified 17 proteins, with PTP4A1 as the most statistically significant biomarker associated to PD vintage and decreased PM function. Altogether, our data suggest that mesothelial cells of FSGS patients are more prone to activate a pro-fibrotic machinery. The role of the proposed biomarkers in the PM pathology deserves further investigation. Our results need further investigations in a larger population to corroborate these findings and investigate a possible increased risk of PM loss of function or development of encapsulating peritoneal sclerosis in FSGS patients, thus to eventually carry out changes in PD treatment and management or implement new solutions.

Peritoneal Dialysis Guidelines 2019 Part 1 (Position paper of the Japanese Society for Dialysis Therapy)

Approximately 10 years have passed since the Peritoneal Dialysis Guidelines were formulated in 2009. Much evidence has been reported during the succeeding years, which were not taken into consideration in the previous guidelines, e.g., the next peritoneal dialysis PD trial of encapsulating peritoneal sclerosis (EPS) in Japan, the significance of angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs), the effects of icodextrin solution, new developments in peritoneal pathology, and a new international recommendation on a proposal for exit-site management. It is essential to incorporate these new developments into the new clinical practice guidelines. Meanwhile, the process of creating such guidelines has changed dramatically worldwide and differs from the process of creating what were “clinical practice guides.” For this revision, we not only conducted systematic reviews using global standard methods but also decided to adopt a two-part structure to create a reference tool, which could be used widely by the society’s members attending a variety of patients. Through a working group consensus, it was decided that Part 1 would present conventional descriptions and Part 2 would pose clinical questions (CQs) in a systematic review format. Thus, Part 1 vastly covers PD that would satisfy the requirements of the members of the Japanese Society for Dialysis Therapy (JSDT). This article is the duplicated publication from the Japanese version of the guidelines and has been reproduced with permission from the JSDT.

Clinical improvement of encapsulating peritoneal sclerosis after challenging course and 6 months of total parenteral nutrition in child with nephronophthisis: a case report

BACKGROUND

Encapsulating peritoneal sclerosis is a rare but potentially lethal complication of long-term peritoneal dialysis that is associated with significant morbidity and mortality. The occurrence of encapsulating peritoneal sclerosis varies worldwide, but is increased in patients maintained on peritoneal dialysis for 5-8 years. The etiology of encapsulating peritoneal sclerosis remains unidentified, and a high index of clinical suspicion is required for diagnosis.

CASE PRESENTATION

We report a 5-year-old Saudi female with end-stage renal disease secondary to nephronophthisis type 2. She underwent peritoneal dialysis for 30 months, with four episodes of peritonitis. She presented with clinical signs of peritonitis. Three days later, she developed septic shock, which required pediatric intensive care unit admission. The peritoneal dialysis catheter was removed because of refractory peritonitis. Her course was complicated by small bowel perforation, and severe adhesions were revealed on abdominal ultrasound and computed tomography, consistent with a diagnosis of EPS. This finding was later confirmed by diagnostic laparotomy performed twice and complicated by recurrent abdominal wall fistula. She received total parenteral nutrition for 6 months and several courses of antibiotics. The patient received supportive treatment including nutritional optimization and treatment for infection. No other treatments, such as immunosuppression, were administered to avoid risk of infection. Following a complicated hospital course, the patient restarted oral intake after 6 months of total parenteral nutrition dependency. Her abdominal fistula resolved completely, and she was maintained on hemodialysis for few years before she received a kidney transplant.

CONCLUSION

When treating patients using peritoneal dialysis, it is important to consider encapsulating peritoneal sclerosis with refractory peritonitis, which is not always easy to identify, particularly if the patient has been maintained on peritoneal dialysis for less than 3 years. Early identification of encapsulating peritoneal sclerosis and appropriate conservative treatment, including nutritional optimization and treatment of infections, are essential to achieve a better prognosis.

Update on the Classification and Pathophysiological Mechanisms of Pediatric Cardiorenal Syndromes

Cardiorenal syndrome (CRS) is defined as a disorder resulting from the abnormal interaction between the heart and kidney, in which acute or chronic dysfunction of one organ may lead to acute and/or chronic dysfunction of the other. The functional interplay between the heart and kidney is characterized by a complex bidirectional symbiotic interaction, regulated by a wide array of both genetic and environmental mechanisms. There are at least five known subtypes of CRS, based on the severity of clinical features and the degree of heart/renal failure. The fourth subtype (cardiorenal syndrome type 4 (CRS4)) is characterized by a primary chronic kidney disease (CKD), which in turn leads to a decreased cardiac function. Impairment of renal function is among the most important pathophysiological factors contributing to heart failure (HF) in the pediatric age group, and cardiovascular complications could be one of the most important causes of mortality in pediatric patients with advanced CKD. In this context, a loss of glomerular filtration rate directly correlates with both the progression of cardiovascular complications in CRS and the risk of HF. This review describes the interaction pathways between the heart and kidney and the recently identified pathophysiological mechanisms underlying pediatric CRS, with a special focus on CRS4, which encompasses both primary CKD and cardiovascular disease (CVD).

Returning to dialysis after kidney allograft failure: the experience of the Italian Registry of Paediatric Chronic Dialysis

BACKGROUND

The need for dialysis after kidney allograft failure (DAGF) is among the top five reasons for dialysis initiation, making this an important topic in clinical nephrology. However, data are scarce on dialysis choice after transplantation and clinical outcomes for DAGF in children.

METHODS

Patients receiving chronic dialysis < 18 years were recorded from January 1991 to January 2019 by the Italian Registry of Pediatric Chronic Dialysis (IRPCD). We investigated factors influencing choice of dialysis modality, patient outcome in terms of mortality, switching dialysis modality, and kidney transplantation.

RESULTS

Among 118 patients receiving DAGF, 41 (35%) were treated with peritoneal dialysis (PD), and 77 (65%) with haemodialysis (HD). Significant predictors for treatment with PD were younger age at dialysis start (OR 0.85 per year increase [95%CI 0.72-1.00]) and PD use before kidney transplantation (OR 8.20 [95%CI 1.82-37.01]). Patients entering DAGF in more recent eras (OR 0.87 per year increase [95%CI 0.80-0.94]) and with more than one dialysis modality before kidney transplantation (OR 0.56 for being treated with PD [0.12-2.59]) were more likely to be initiated on HD. As compared to patients on HD, those treated with PD exhibited increased but non-significant mortality risk (HR 2.15 [95%CI 0.54-8.6]; p = 0.28) and higher prevalence of dialysis-related complications during DAGF (p = 0.002) CONCLUSIONS: Patients entering DAGF in more recent years are more likely to be initiated on HD. In this specific population of children, use of PD seems associated with a more complicated course. A higher resolution version of the Graphical abstract is available as Supplementary information.

Encapsulating Peritoneal Sclerosis: Pathophysiology and Current Treatment Options

Encapsulating peritoneal sclerosis (EPS) is a life-threatening complication of long-term peritoneal dialysis (PD), which may even occur after patients have switched to hemodialysis (HD) or undergone kidney transplantation. The incidence of EPS varies across the globe and increases with PD vintage. Causative factors are the chronic exposure to bioincompatible PD solutions, which cause long-term modifications of the peritoneum, a high peritoneal transporter status involving high glucose concentrations, peritonitis episodes, and smoldering peritoneal inflammation. Additional potential causes are predisposing genetic factors and some medications. Clinical symptoms comprise signs of intestinal obstruction and a high peritoneal transporter status with incipient ultrafiltration failure. In radiological, macro-, and microscopic studies, a massively fibrotic and calcified peritoneum enclosed the intestine and parietal wall in such cases. Empirical treatments commonly used are corticosteroids and tamoxifen, which has fibrinolytic properties. Immunosuppressants like azathioprine, mycophenolate mofetil, or mTOR inhibitors may also help with reducing inflammation, fibrin deposition, and collagen synthesis and maturation. In animal studies, N-acetylcysteine, colchicine, rosiglitazone, thalidomide, and renin-angiotensin system (RAS) inhibitors yielded promising results. Surgical treatment has mainly been performed in severe cases of intestinal obstruction, with varying results. Mortality rates are still 25–55% in adults and about 14% in children. To reduce the incidence of EPS and improve the outcome of this devastating complication of chronic PD, vigorous consideration of the risk factors, early diagnosis, and timely discontinuation of PD and therapeutic interventions are mandatory, even though these are merely based on empirical evidence.

Encapsulating Peritoneal Sclerosis

Encapsulating peritoneal sclerosis (EPS) is a rare but serious complication of peritoneal dialysis. In this review, we describe the clinical picture and histologic changes to the peritoneal membrane that are associated with EPS and provide an update on current diagnosis and management. We also discuss the recent studies that have suggested that the use of more biocompatible solutions containing lower concentrations of glucose degradation product that often are pH neutral in combination with a change in clinical practice (reducing glucose exposure and monitoring peritoneal membrane function) might ameliorate peritoneal degeneration, reduce the incidence of EPS, and minimize the severity of the disease.

A propensity-matched comparison of hard outcomes in children on chronic dialysis

Data concerning outcomes of children on hemodialysis (HD) and peritoneal dialysis (PD) are scarce and frequently derived from single-center experiences. We sought to compare survival and transplantation rates in a large cohort of PD and HD patients. We extracted all patients initiating dialysis under 16 years of age between 2004 and 2013 from the Italian Registry of Pediatric Chronic Dialysis. Patients on PD were propensity-matched to those on HD based on gender, age, primary cause of ESRD, and the number of co-morbidities. Stratified Cox proportional hazard models were used to compare outcomes by dialysis modality. Three hundred ten patients were matched from 452 incident patients. In the unmatched cohort, PD patients were younger, more likely to be diagnosed with CAKUT, and had a higher urine output than HD patients. In the propensity-matched cohort, covariates were balanced between the two groups. At 2 years, the cumulative hazard ratio for death was similar (CHR 0.95, 95% CI 0.17-5.20) for HD relative to PD patients; and at 5 years, the CHR was lower for HD patients (0.22 95% CI 0.16-0.29). The cumulative incidence of transplantation at 3 years after dialysis initiation was 60.9% in HD patients and 59.7% in PD patients, with a CHR of 1.03 (95% CI 0.73-1.45).

CONCLUSIONS

Pediatric PD and HD patients have distinct characteristics. After controlling for treatment-selection biases, children selected to start on PD or HD exhibit a similar mortality risk during the first 2 years on treatment, after which this risk increases in PD children. What is Known: • Few studies have compared hard outcomes in children on maintenance dialysis. • Children started on different dialysis modalities have distinct characteristics that impact on survival. What is New: • After controlling for treatment-selection biases, children selected to start dialysis on PD or HD exhibit a similar mortality risk during the first 2 years on treatment, after which this risk appears to be increased in PD children. • An "integrative care" approach should be used in children on PD, switching them to HD when PD-related morbidity tends to increase.

Miscellaneous conditions of the peritoneal cavity--peritoneal tumors, pseudomyxoma, mesothelioma, fibroblastic reaction, cocoon, cystic lymphatic malformations, blue-bleb, and chylous ascites

The peritoneum is subject to both primary neoplasia and secondary malignancy from direct, trans-coelomic, or hematogenous spread from any cancer. The knowledge base in the pediatric age group is very limited due to the rarity of peritoneal conditions in children, and much of the information is extrapolated from adult literature. There have been few reports in the pediatric population on the diagnosis and management of peritoneal conditions including peritoneal malignancy. In this article, we aim to highlight some of these conditions and the treatments available with a special emphasis on the evolving role of cytoreduction surgery and hyperthermic intraperitoneal chemotherapy in the treatment of certain peritoneal malignancies in children.

Encapsulating peritoneal sclerosis in children

Encapsulating peritoneal sclerosis (EPS) is a rare but extremely serious complication of peritoneal dialysis (PD). While EPS has been well recognized in adults on long-term PD, and children can spend many years on PD before a transplant becomes available, only a small number of children with EPS have been described. Two European pediatric registries have recently reported on the prevalence, potential risk factors and outcomes of EPS in children. Although the prevalence of EPS is comparable to that published in adult registries, the outcome of pediatric EPS is significantly better and carries a lower mortality. All studies have shown a greater risk of EPS with a longer dialysis vintage, but it is not known why some individuals are susceptible to EPS development. In this review we discuss current views on the epidemiology, pathogenesis and management strategies for EPS. The hope of the authors is that this review will alert pediatric nephrologists to this rare but extremely serious complication of chronic PD. In the future, collaborative research and the establishment of a pediatric EPS registry may be of importance in helping pediatric nephrologists to recognize the early warning signs of EPS development and thereby to develop strategies for its prevention and optimal management.