Indications and relative renal function for paediatric nephrectomy over a 20-year period

Obstruction from Deflux leading to significant kidney function loss and chemotherapeutic challenges in pediatric Ewing sarcoma

This report presents the case of an 8-year-old female with a history of vesicoureteral reflux (VUR) treated with Deflux injections, who developed Ewing sarcoma metastasized to the lungs. Despite the initial resolution of VUR following Deflux procedures, recurrent urinary tract infections prompted further evaluation revealing significant ureteral obstruction. Pre-chemotherapy workup included renal ultrasonography, nuclear medicine renal scan, and cystogram, identifying obstructive uropathy necessitating bilateral ureteral stent placement. This discussion encompasses the challenges of managing VUR, Deflux complications, and the importance of tailored follow-up protocols.

Induction of reactive oxygen species by mechanical stretch drives endothelin production in neonatal pig renal epithelial cells

Vasoactive endothelin (ET) is generated by ET converting enzyme (ECE)-induced proteolytic processing of pro-molecule big ET to biologically active peptides. H2O2 has been shown to increase the expression of ECE1 via transactivation of its promoter. The present study demonstrates that H2O2 triggered ECE1-dependent ET1-3 production in neonatal pig proximal tubule (PT) epithelial cells. A uniaxial stretch of PT cells decreased catalase, increased NADPH oxidase (NOX)2 and NOX4, and increased H2O2 levels. Stretch also increased cellular ECE1, an effect reversed by EUK-134 (a synthetic superoxide dismutase/catalase mimetic), NOX inhibitor apocynin, and siRNA-mediated knockdown of NOX2 and NOX4. Short-term unilateral ureteral obstruction (UUO), an inducer of renal tubular cell stretch and oxidative stress, increased renal ET1-3 generation and vascular resistance (RVR) in neonatal pigs. Despite removing the obstruction, UUO-induced increase in RVR persisted, resulting in early acute kidney injury (AKI). ET receptor (ETR)-operated Ca2+ entry in renal microvascular smooth muscle (SM) via transient receptor potential channel 3 (TRPC3) channels reduced renal blood flow and increased RVR. Although acute reversible UUO (rUUO) did not change protein expression levels of ETR and TRPC3 in renal microvessels, inhibition of ECE1, ETR, and TRPC3 protected against renal hypoperfusion, RVR increase, and early AKI. These data suggest that mechanical stretch-driven oxyradical generation stimulates ET production in neonatal pig renal epithelial cells. ET activates renal microvascular SM TRPC3, leading to persistent vasoconstriction and reduction in renal blood flow. These mechanisms may underlie rUUO-induced renal insufficiency in infants.

Demirtas Two-Step Treatment Model in Hypofunctional-Obstructed Kidneys: An Extended Series and Long-Term Prospective Results

Aim: This study aimed to present the short- and long-term results of Demirtas two-step treatment model in patients with obstructed-hydronephrotic kidneys functioning below 10%, and before deciding on nephrectomy, to evaluate whether this method can contribute to the accurate assessment.

Material and methods: This prospective study included patients with unilateral renal obstruction and renal parenchymal loss assessed by computed tomography and whose renal function was found to be below 10% in Tc-99m-dimercaptosuccinic acid. In the first step, percutaneous nephrostomy (PCN) was performed. Two weeks later, the second step was performed, in which patients were offered nephrectomy (if renal function was <10%) or etiology-based treatment (if renal function was ≥10%).

Results: Thirty-eight patients were included in the study, comprising 20 (52.6%) men and 18 (47.4%) women with a mean age of 51.3±16.8 years. Mean baseline renal function was 6.0%, which increased to 10.8% two weeks after PCN (p=0.001). Renal function increased to above 10% in 20 (52.6%) out of 38 patients. Of these, 17 patients underwent etiology-based treatment and baseline, two-week, and 12-month renal function levels were 7.0%, 17.5%, and 18.8%, respectively (p<0.001).

Conclusion: Demirtas two-step treatment model introduced in the present study can be recommended as a standard treatment modality in unilaterally obstructed kidneys functioning below 10% ability.

A Comparative Study of Conservation, Endovascular Embolization Therapy, and Surgery for Blunt Renal Trauma

BACKGROUND In this study, we evaluated the advantages and disadvantages of angioembolization in patients with Grade III-V blunt renal trauma compared with other treatments. MATERIAL AND METHODS We prospectively collected data on patients hospitalized for Grade III-V blunt renal trauma. Organ damage was graded according to the American Association for the Surgery of Trauma (AAST) criteria. Initial grouping was then performed according to the hemodynamics and "initial treatment". The eligible patients were divided into 3 groups: conservative treatment group (Group A), arterial embolization group (Group B), and surgical group (Group C). The success rate, significance, and follow-up renal function were evaluated. RESULTS In Group B of Grade IV, estimated glomerular filtration rate (eGFR) and serum creatinine (Scr) levels were slightly decreased and increased, respectively, after embolization compared with before embolization (P=0.002, P=0.039). In Grade V, the eGFR of Group B after embolization was lower than before embolization (P=0.041); The levels of serum urea (Urea) and Scr in Group B after treatment were higher than those before treatment (P=0.042, P=0.024). Conservative treatment and angioembolization were better than exploration in protecting renal function of Grade IV (P=0.035 and P=0.047, respectively). CONCLUSIONS The success rate of angioembolization was high and protected renal function to the greatest extent, and there were no differences in renal function at long-term follow-up. However, it is difficult to manage renal vessel laceration or avulsion by embolization alone, and various endovascular therapies are required to protect the function of residual kidneys.

An update on renal scarring after urinary tract infection in children: what are the risk factors?

AIM

The aim of this study was to present updated information on clinical, laboratory, and imaging risk factors and predictors of renal scarring after first or recurrent febrile UTIs, which may be associated with renal scarring.

METHODS

PubMed was searched for current data on possible risk factors and predictors of renal scarring after febrile urinary tract infections in children.

RESULTS

Recurrence of acute pyelonephritis is an independent risk factor for renal scarring, while the duration of fever before treatment initiation is mainly associated with acute pyelonephritis and its severity. Severe vesicoureteral reflux is an important independent risk factor for the development of renal scarring after a febrile urinary tract infection.

CONCLUSIONS

Certain clinical parameters could be used to identify children at high risk for renal scarring after febrile urinary tract infection, helping clinicians to reserve dimercaptosuccinic acid scan for selected cases.

Early and late adverse renal effects after potentially nephrotoxic treatment for childhood cancer

BACKGROUND

Improvements in diagnostics and treatment for paediatric malignancies resulted in a major increase in survival. However, childhood cancer survivors (CCS) are at risk of developing adverse effects caused by multimodal treatment for their malignancy. Nephrotoxicity is a known side effect of several treatments, including cisplatin, carboplatin, ifosfamide, radiotherapy and nephrectomy, and can cause glomerular filtration rate (GFR) impairment, proteinuria, tubulopathy, and hypertension. Evidence about the long-term effects of these treatments on renal function remains inconclusive. It is important to know the risk of, and risk factors for, early and late adverse renal effects, so that ultimately treatment and screening protocols can be adjusted. This review is an update of a previously published Cochrane Review.

OBJECTIVES

To evaluate existing evidence on the effects of potentially nephrotoxic treatment modalities on the prevalence of renal dysfunction in survivors treated for childhood cancer with a median or mean survival of at least one year after cessation of treatment, where possible in comparison with the general population or CCS treated without potentially nephrotoxic treatment. In addition, to evaluate evidence on associated risk factors, such as follow-up duration, age at time of diagnosis and treatment combinations, as well as the effect of doses.

SEARCH METHODS

On 31 March 2017 we searched the following electronic databases: CENTRAL, MEDLINE and Embase. In addition, we screened reference lists of relevant studies and we searched the congress proceedings of the International Society of Pediatric Oncology (SIOP) and The American Society of Pediatric Hematology/Oncology (ASPHO) from 2010 to 2016/2017.

SELECTION CRITERIA

Except for case reports, case series and studies including fewer than 20 participants, we included studies with all study designs that reported on renal function (one year or longer after cessation of treatment), in CCS treated before the age of 21 years with cisplatin, carboplatin, ifosfamide, radiation involving the kidney region, a nephrectomy, or a combination of two or more of these treatments. When not all treatment modalities were described or the study group of interest was unclear, a study was not eligible for the evaluation of prevalence. We still included it for the assessment of risk factors if it had performed a multivariable analysis.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed study selection, 'Risk of bias' assessment and data extraction using standardised data collection forms. We performed analyses according to the guidelines of the Cochrane Handbook for Systematic Reviews of Interventions.

MAIN RESULTS

Apart from the remaining 37 studies included from the original review, the search resulted in the inclusion of 24 new studies. In total, we included 61 studies; 46 for prevalence, six for both prevalence and risk factors, and nine not meeting the inclusion criteria, but assessing risk factors. The 52 studies evaluating the prevalence of renal dysfunction included 13,327 participants of interest, of whom at least 4499 underwent renal function testing. The prevalence of adverse renal effects ranged from 0% to 84%. This variation may be due to diversity of included malignancies, received treatments, reported outcome measures, follow-up duration and the methodological quality of available evidence.Seven out of 52 studies, including 244 participants, reported the prevalence of chronic kidney disease, which ranged from 2.4% to 32%.Of these 52 studies, 36 studied a decreased (estimated) GFR, including at least 432 CCS, and found it was present in 0% to 73.7% of participants. One eligible study reported an increased risk of glomerular dysfunction after concomitant treatment with aminoglycosides and vancomycin in CCS receiving total body irradiation (TBI). Four non-eligible studies assessing a total cohort of CCS, found nephrectomy and (high-dose (HD)) ifosfamide as risk factors for decreased GFR. The majority also reported cisplatin as a risk factor. In addition, two non-eligible studies showed an association of a longer follow-up period with glomerular dysfunction.Twenty-two out of 52 studies, including 851 participants, studied proteinuria, which was present in 3.5% to 84% of participants. Risk factors, analysed by three non-eligible studies, included HD cisplatin, (HD) ifosfamide, TBI, and a combination of nephrectomy and abdominal radiotherapy. However, studies were contradictory and incomparable.Eleven out of 52 studies assessed hypophosphataemia or tubular phosphate reabsorption (TPR), or both. Prevalence ranged between 0% and 36.8% for hypophosphataemia in 287 participants, and from 0% to 62.5% for impaired TPR in 246 participants. One non-eligible study investigated risk factors for hypophosphataemia, but could not find any association.Four out of 52 studies, including 128 CCS, assessed the prevalence of hypomagnesaemia, which ranged between 13.2% and 28.6%. Both non-eligible studies investigating risk factors identified cisplatin as a risk factor. Carboplatin, nephrectomy and follow-up time were other reported risk factors.The prevalence of hypertension ranged from 0% to 50% in 2464 participants (30/52 studies). Risk factors reported by one eligible study were older age at screening and abdominal radiotherapy. A non-eligible study also found long follow-up time as risk factor. Three non-eligible studies showed that a higher body mass index increased the risk of hypertension. Treatment-related risk factors were abdominal radiotherapy and TBI, but studies were inconsistent.Because of the profound heterogeneity of the studies, it was not possible to perform meta-analyses. Risk of bias was present in all studies.

AUTHORS' CONCLUSIONS

The prevalence of adverse renal effects after treatment with cisplatin, carboplatin, ifosfamide, radiation therapy involving the kidney region, nephrectomy, or any combination of these, ranged from 0% to 84% depending on the study population, received treatment combination, reported outcome measure, follow-up duration and methodological quality. With currently available evidence, it was not possible to draw solid conclusions regarding the prevalence of, and treatment-related risk factors for, specific adverse renal effects. Future studies should focus on adequate study designs and reporting, including large prospective cohort studies with adequate control groups when possible. In addition, these studies should deploy multivariable risk factor analyses to correct for possible confounding. Next to research concerning known nephrotoxic therapies, exploring nephrotoxicity after new therapeutic agents is advised for future studies. Until more evidence becomes available, CCS should preferably be enrolled into long-term follow-up programmes to monitor their renal function and blood pressure.

Paediatric nephrectomy: Patterns, indications and outcome in a developing country

Background

Patterns of and indications for nephrectomy vary in different age groups, geographical locations and time periods. In some series nephrectomies were mainly for malignant conditions while in others they were predominantly for non-malignant conditions. Such data on patterns, indications, and outcomes of nephrectomy in children is limited in our environment.

Objectives

To evaluate nephrectomy in childhood at the Sub-Department of Pediatric Surgery University of Nigeria Teaching Hospital, Ituku/Ozalla Enugu with a focus on pattern, indications, and outcome.

Materials And Methods

Medical records of all patients aged =16years who had nephrectomy from January 2007 to December 2016 were studied with emphasis on age, sex, side of nephrectomy, duration of symptoms before presentation, indication for nephrectomy, in-hospital complications, length of hospital stay, in-hospital mortality. SPSS version 15 was used for data entry and analysis.

Results

There were 52 nephrectomies in 32 males and 20 females. They were for 35 malignant and 17 non-malignant conditions. Most of the malignancies were Wilms tumour (34/35) while non-malignant conditions were late-presenting pelvi-ureteric junction obstruction (9), large multi-cystic dysplastic kidneys (4), renal trauma with pedicle avulsion (1), posterior urethral valve with atrophic kidney (1), duplex system with nonfunctioning upper pole moiety (2). Mean age at nephrectomy was 5.10±3.66 years (range 7 weeks to 16 years); 59% of the nephrectomies were on the left and 41% on the right. Mean duration of hospital stay was 31.78±16.59 days (range 7–66 days). In-hospital mortality rate was 5.8%.

Conclusions

In our unit, nephroblastoma is the main indication for pediatric nephrectomy and were the only indications in females; neglected pelvi-ureteric junction obstruction was the major non-malignant indication and occurred only in males; most nephrectomies were done in the age range of 1–5 years; nephron-sparing nephrectomy, major morbidity, re-operation are uncommon and in-hospital mortality from nephrectomy is still high at 5.8%.

Image-defined risk factors for nephrectomy in patients undergoing neuroblastoma resection

BACKGROUND

Although nephrectomy rates are higher in children with neuroblastoma who have image-defined risk factors and/or high-risk disease who undergo resection prior to chemotherapy, no published data outline the key radiographic and clinical characteristics associated with nephrectomy.

METHODS

With IRB approval, imaging studies of children undergoing primary resection of intraabdominal neuroblastoma between 2000 and 2014 were retrospectively reviewed. Fisher's exact and Wilcoxon rank-sum tests were used to compare categorical and continuous variables, respectively, with p-values adjusted for multiple testing using the false discovery rate approach.

RESULTS

Twenty-seven of 380 consecutive patients with CT imaging obtained prior to primary neuroblastoma resection underwent partial or total nephrectomy. On preoperative imaging, renal vessel narrowing and encasement and tumor invasion of the renal hilum, pelvis, and/or parenchyma were present significantly more frequently among patients undergoing nephrectomy. Delayed renal excretion of contrast, hydronephrosis, and tumors with MYCN amplification were also more prevalent in the nephrectomy group.

CONCLUSION

Encasement and narrowing of renal vessels, delayed excretion, and tumor invasion into the kidney, particularly pelvis and capsule invasion, are significantly associated with partial or total nephrectomy at initial neuroblastoma resection. These observations provide valuable information for surgical planning as well as presurgical discussions with families prior to neuroblastoma resection.