Risk factors for nephrotoxicity after ifosfamide treatment in children: a UKCCSG Late Effects Group study. United Kingdom Children's Cancer Study Group

Chapter 3: Management of kidney injury caused by cancer drug therapy, from clinical practice guidelines for the management of kidney injury during anticancer drug therapy 2022

Cisplatin should be administered with diuretics and Magnesium supplementation under adequate hydration to avoid renal impairment. Patients should be evaluated for eGFR (estimated glomerular filtration rate) during the treatment with pemetrexed, as kidney injury has been reported. Pemetrexed should be administered with caution in patients with a CCr (creatinine clearance) < 45 mL/min. Mesna is used to prevent hemorrhagic cystitis in patients receiving ifosfamide. Febuxostat is effective in avoiding hyperuricemia induced by TLS (tumor lysis syndrome). Preventative rasburicase is recommended in high-risk cases of TLS. Thrombotic microangiopathy could be triggered by anticancer drugs and there is no evidence of efficacy of plasma exchange therapy. When proteinuria occurs during treatment with anti-angiogenic agents or multi-kinase inhibitors, dose reductions or interruptions based on grading should be considered. Grade 3 proteinuria and renal dysfunction require urgent intervention, including drug interruption or withdrawal, and referral to a nephrologist should be considered. The first-line drugs used for blood pressure elevation due to anti-angiogenic agents are ACE (angiotensin-converting enzyme) inhibitors and ARBs (angiotensin receptor blockers). The protein binding of drugs and their pharmacokinetics are considerably altered in patients with hypoalbuminemia. The clearance of rituximab is increased in patients with proteinuria, and the correlation with urinary IgG suggests similar pharmacokinetic changes when using other antibody drugs. AIN (acute interstitial nephritis) is the most common cause of ICI (immune checkpoint inhibitor)-related kidney injury that is often treated with steroids. The need for renal biopsy in patients with kidney injury that occurs during treatment with ICI remains controversial.

Chapter 4: CKD treatment in cancer survivors, from Clinical Practice Guidelines for the Management of Kidney Injury During Anticancer Drug Therapy 2022

Chronic kidney disease (CKD) is one of the most disabling disorders with significant comorbidity and mortality. Incidence and prevalence of CKD in cancer survivors are remarkably high in both adults and pediatric patients. The reasons for this high incidence/prevalence are multifold but kidney damage by cancer itself and cancer treatment (pharmacotherapy/surgery/radiation) are the main reasons. Since cancer survivors commonly have significant comorbidities, risk of cancer recurrence, limited physical function or life expectancy, special attentions should be paid when considering the treatment of CKD and its complications. Especially, shared decision-making should be considered when selecting the renal replacement therapies with as much information/facts/evidence as possible.

Chapter 1: Evaluation of kidney function in patients undergoing anticancer drug therapy, from clinical practice guidelines for the management of kidney injury during anticancer drug therapy 2022

The prevalence of CKD may be higher in patients with cancer than in those without due to the addition of cancer-specific risk factors to those already present for CKD. In this review, we describe the evaluation of kidney function in patients undergoing anticancer drug therapy. When anticancer drug therapy is administered, kidney function is evaluated to (1) set the dose of renally excretable drugs, (2) detect kidney disease associated with the cancer and its treatment, and (3) obtain baseline values for long-term monitoring. Owing to some requirements for use in clinical practice, a GFR estimation method such as the Cockcroft-Gault, MDRD, CKD-EPI, and the Japanese Society of Nephrology's GFR estimation formula has been developed that is simple, inexpensive, and provides rapid results. However, an important clinical question is whether they can be used as a method of GFR evaluation in patients with cancer. When designing a drug dosing regimen in consideration of kidney function, it is important to make a comprehensive judgment, recognizing that there are limitations regardless of which estimation formula is used or if GFR is directly measured. Although CTCAEs are commonly used as criteria for evaluating kidney disease-related adverse events that occur during anticancer drug therapy, a specialized approach using KDIGO criteria or other criteria is required when nephrologists intervene in treatment. Each drug is associated with the different disorders related to the kidney. And various risk factors for kidney disease associated with each anticancer drug therapy.

Ewing Sarcoma Drug Therapy: Current Standard of Care and Emerging Agents

Ewing sarcoma is a translocation-associated sarcoma mainly impacting adolescents and young adults. The classic translocation (EWSR1::FLI1) leads to a fusion oncoprotein that functions as an aberrant transcription factor. As such, the oncogenic driver of this disease has been difficult to target pharmacologically and, therefore, the systemic therapies used to treat patients with Ewing sarcoma have typically been non-selective cytotoxic chemotherapy agents. The current review highlights recent clinical trials from the last decade that provide the evidence base for contemporary drug therapy for patients with Ewing sarcoma, while also highlighting novel therapies under active clinical investigation in this disease. We review recent trials that have led to the establishment of interval-compressed chemotherapy as an international standard for patients with newly diagnosed localized disease. We further highlight recent trials that have shown a lack of demonstrable benefit from high-dose chemotherapy or IGF-1R inhibition for patients with newly diagnosed metastatic disease. Finally, we provide an overview of chemotherapy regimens and targeted therapies used in the management of patients with recurrent Ewing sarcoma.

Nephrotoxicity associated with anticancer agents: perspective on onconephrology from nephrologists

Nephrotoxicity is one of the most important complications in cancer patients. In particular, acute kidney injury (AKI) is known to be associated with discontinuing effective oncological treatments, longer hospitalizations, increased costs, and a higher risk of death. In addition to acute kidney injury, clinical signs associated with nephrotoxicity during treatment with anticancer agents include chronic kidney disease, proteinuria, hypertension, electrolyte abnormalities, and other characteristic manifestations. Many of these signs are caused both by cancer treatment as well as by cancer itself. Therefore, it is important to carefully recognize whether the underlying causes of renal impairment in cancer patients are cancer-related, treatment-related, or both. This review describes the epidemiology and pathophysiology of anticancer agent-induced acute kidney injury, proteinuria, hypertension, and other characteristic manifestations.

KIdney aNd blooD prESsure ouTcomes in Childhood Cancer Survivors: Description of Clinical Research Protocol of the KINDEST-CCS Study

Background

Approximately 30% of childhood cancer survivors (CCSs) will develop chronic kidney disease (CKD) or hypertension 15 to 20 years after treatment ends. The incidence of CKD and hypertension in the 5-year window after cancer therapy is unknown. Moreover, extent of monitoring of CCS with CKD and associated complications in current practice is underexplored. To inform the development of new and existing care guidelines for CCS, the epidemiology and monitoring of CKD and hypertension in the early period following cancer therapy warrants further investigation.

Objective

To describe the design and methods of the KIdney aNd blooD prESsure ouTcomes in Childhood Cancer Survivors study, which aims to evaluate the burden of late kidney and blood pressure outcomes in the first ~10 years after cancer therapy, the extent of appropriate screening and complications monitoring for CKD and hypertension, and whether patient, disease/treatment, or system factors are associated with these outcomes.

Design

Two distinct, but related studies; a prospective cohort study and a retrospective cohort study.

Setting

Five Ontario pediatric oncology centers.

Patients

The prospective study will involve 500 CCS at high risk for these late effects due to cancer therapy, and the retrospective study involves 5,000 CCS ≤ 18 years old treated for cancer between January 2008 and December 2020.

Measurements

Chronic kidney disease is defined as Estimated glomerular filtration rate <90 mL/min/1.73 m² or albumin-to-creatinine ratio ≥ 3mg/mmol. Hypertension is defined by 2017 American Academy of Pediatrics guidelines.

Methods

Prospective study: we aim to investigate CKD and hypertension prevalence and the extent to which they persist at 3- and 5-year follow-up in CCS after cancer therapy. We will collect detailed biologic and clinical data, calculate CKD and hypertension prevalence, and progression at 3- and 5-years post-therapy. Retrospective study: we aim to investigate CKD and hypertension monitoring using administrative and health record data. We will also investigate the validity of CKD and hypertension administrative definitions in this population and the incidence of CKD and hypertension in the first ~10 years post-cancer therapy. We will investigate whether patient-, disease/treatment-, or system-specific factors modify these associations in both studies.

Limitations

Results from the prospective study may not be generalizable to non-high-risk CCS. The retrospective study is susceptible to surveillance bias.

Conclusions

Our team and knowledge translation plan is engaging patient partners, researchers, knowledge users, and policy group representatives. Our work will address international priorities to improve CCS health, provide the evidence of new disease burden and practice gaps to improve CCS guidelines, implement and test revised guidelines, plan trials to reduce CKD and hypertension, and improve long-term CCS health.

Acute Kidney Injury in Critically Ill Patients with Cancer

Advances in cancer therapy have significantly improved overall patient survival; however, AKI remains a common complication in patients with cancer, occurring in anywhere from 11% to 22% of patients, depending on patient-related or cancer-specific factors. Critically ill patients with cancer as well as patients with certain malignancies (e.g., leukemias, lymphomas, multiple myeloma, and renal cell carcinoma) are at highest risk of developing AKI. AKI may be a consequence of the underlying malignancy itself or from the wide array of therapies used to treat it. Cancer-associated AKI can affect virtually every compartment of the nephron and can present as subclinical AKI or as overt acute tubular injury, tubulointerstitial nephritis, or thrombotic microangiopathy, among others. AKI can have major repercussions for patients with cancer, potentially jeopardizing further eligibility for therapy and leading to greater morbidity and mortality. This review highlights the epidemiology of AKI in critically ill patients with cancer, risk factors for AKI, and common pathologies associated with certain cancer therapies, as well as the management of AKI in different clinical scenarios. It highlights gaps in our knowledge of AKI in patients with cancer, including the lack of validated biomarkers, as well as evidence-based therapies to prevent AKI and its deleterious consequences.

Prospective Evaluation of Kidney Function in Long-Term Survivors of Pediatric CNS Tumors

Purpose: Numerous acute effects of chemotherapeutics on kidney function are well described. However, data on the long-term effects of chemotherapy in the growing population of childhood central nervous system (CNS) tumor survivors is limited. We aimed to evaluate the kidney function of a cohort of long-term CNS tumor survivors treated with different standard chemotherapeutic regimens. Methods: Patients treated for a CNS tumor were prospectively evaluated up to 12 years after completion of their therapy. Examination of kidney function was performed during routine follow-up visits. Blood pressure and blood and urine parameters were analyzed for kidney function evaluation. Glomerular function was assessed by calculating the estimated glomerular filtration rate (eGFR), tubular functions were analyzed by measuring serum electrolytes, bicarbonate and phosphate reabsorption, and proteinuria was assessed by calculating the protein/creatinine ratio and phosphate reabsorption. Results: None of the 65 patients evaluated suffered from clinically relevant kidney impairment (eGFR < 90 mL/min/L, 73 m2). There was no association between chemotherapy dose and eGFR. Only two patients showed mild signs of tubulopathy and 11 patients were diagnosed with elevated blood pressure. Conclusion: With adequate supportive measures, such as sufficient hydration according to chemotherapy protocol guidelines, as well as avoidance or close monitoring of additional nephrotoxic medication, impaired kidney function is rare in CNS tumor survivors treated with standard chemotherapy. Nonetheless, long-term follow-up is essential for early detection of mild impairment of kidney function.

Serum protein and electrolyte imbalances are associated with chemotherapy induced neutropenia

Introduction

Cancer and its treatment using various chemotherapeutic agents can have many adverse side effects. These side effects often result in significant changes in haematological and biochemical composition of blood. As a result, the regular monitoring of serum biochemical and haematological changes plays an important role in management of disease. The present study aimed to determine the relationship between haematological and biochemical changes in neutropenic cancer patients following chemotherapy. Specifically we evaluated the association between neutrophil count and serum proteins and electrolytes.

Methods

For this purpose we analysed retrospectively collected laboratory results from two independent patient cohorts. Each cohort was divided into a control group consisting of patients with normal haematological parameters and a study group which included patients with reduced neutrophil counts. Neutropenic patients (study group) were cancer patients on chemotherapy.

Results and conclusion

Blood samples of cancer patients in study group showed reduction in haemoglobin, neutrophils and platelets. Neutropenic group showed a significant reduction in serum albumin, total protein, calcium, and potassium. Our results show that patients with severe neutropenia had pronounced changes in serum protein and electrolytes and increased incidence of abnormal serum protein and electrolyte level. The changes in the neutrophil counts showed a positive correlation with the changes in serum protein and electrolyte levels. A similar trend was seen in both the patient cohorts: the discovery set (176 patients) and the validation set (200 patients). Taken together our results suggest that chemotherapy-induced neutropenia is associated with dysregulation in haemoglobin, platelets, serum proteins and electrolytes.

Pediatric Onco-Nephrology: Time to Spread the Word-Part II: Long-Term Kidney Outcomes in Survivors of Childhood Malignancy and Malignancy after Kidney Transplant

Onco-nephrology is a recent and evolving medical subspecialty devoted to the care of patients with kidney disease and unique kidney-related complications in the context of cancer and its treatments, recognizing that management of kidney disease as well as the cancer itself will improve survival and quality of life. While this area has received much attention in the adult medicine sphere, similar emphasis in the pediatric realm has not yet been realized. As in adults, kidney involvement in children with cancer extends beyond the time of initial diagnosis and treatment. Many interventions, such as chemotherapy, stem cell transplant, radiation, and nephrectomy, have long-term kidney effects, including the development of chronic kidney disease (CKD) with subsequent need for dialysis and/or kidney transplant. Thus, with the improved survival of children with malignancy comes the need for ongoing monitoring of kidney function and early mitigation of kidney-related comorbidities. In addition, children with kidney transplant are at higher risk of developing malignancies than their age-matched peers. Pediatric nephrologists thus need to be aware of issues related to cancer and its treatments as they impact their own patients. These facts emphasize the necessity of pediatric nephrologists and oncologists working closely together in managing these children and highlight the importance of bringing the onco-nephrology field to our growing list of pediatric nephrology subspecialties.

Outcomes of kidney injury including dialysis and kidney transplantation in pediatric oncology and hematopoietic cell transplant patients

Pediatric oncology and hematopoietic cell transplant (HCT) patients are susceptible to both acute kidney injury (AKI) and chronic kidney disease (CKD). The etiologies of AKI vary but include tumor infiltration, radiation, drug-induced toxicity, and fluid and electrolyte abnormalities including tumor lysis syndrome. HCT patients can also have additional complications such as sinusoidal obstructive syndrome, graft-versus-host disease, or thrombotic microangiopathy. For patients with severe AKI requiring dialysis, multiple modalities can be used successfully, although continuous kidney replacement therapy (CKRT) is often the principal modality for critically ill patients. While increasing numbers of pediatric cancer and HCT patients are now surviving long term, they remain at risk for a number of chronic medical conditions, including CKD. Certain high-risk patients, due to underlying risk factors or treatment-related complications, eventually develop kidney failure and may require kidney replacement therapies. Management of co-morbidities and complications associated with kidney failure, including use of erythropoietin for anemia and potential need for ongoing cancer-related treatment while on dialysis, is an additional consideration in this patient population. Kidney transplantation can be successfully performed in pediatric cancer survivors, although additional features such as specific cancer diagnosis and duration of remission should be considered.

RNA sequencing and functional studies of patient-derived cells reveal that neurexin-1 and regulators of this pathway are associated with poor outcomes in Ewing sarcoma

Purpose

The development of biomarkers and molecularly targeted therapies for patients with Ewing sarcoma (ES) in order to minimise morbidity and improve outcome is urgently needed. Here, we set out to isolate and characterise patient-derived ES primary cell cultures and daughter cancer stem-like cells (CSCs) to identify biomarkers of high-risk disease and candidate therapeutic targets.

Methods

Thirty-two patient-derived primary cultures were established from treatment-naïve tumours and primary ES-CSCs isolated from these cultures using functional methods. By RNA-sequencing we analysed the transcriptome of ES patient-derived cells (n = 24) and ES-CSCs (n = 11) to identify the most abundant and differentially expressed genes (DEGs). Expression of the top DEG(s) in ES-CSCs compared to ES cells was validated at both RNA and protein levels. The functional and prognostic potential of the most significant gene (neurexin-1) was investigated using knock-down studies and immunohistochemistry of two independent tumour cohorts.

Results

ES-CSCs were isolated from all primary cell cultures, consistent with the premise that ES is a CSC driven cancer. Transcriptional profiling confirmed that these cells were of mesenchymal origin, revealed novel cell surface targets for therapy that regulate cell-extracellular matrix interactions and identified candidate drivers of progression and relapse. High expression of neurexin-1 and low levels of regulators of its activity, APBA1 and NLGN4X, were associated with poor event-free and overall survival rates. Knock-down of neurexin-1 decreased viable cell numbers and spheroid formation.

Conclusions

Genes that regulate extracellular interactions, including neurexin-1, are candidate therapeutic targets in ES. High levels of neurexin-1 at diagnosis are associated with poor outcome and identify patients with localised disease that will relapse. These patients could benefit from more intensive or novel treatment modalities. The prognostic significance of neurexin-1 should be validated independently.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13402-021-00619-8.

Pediatric onco-nephrology: time to spread the word : Part I: early kidney involvement in children with malignancy

Onco-nephrology has been a growing field within the adult nephrology scope of practice. Even though pediatric nephrologists have been increasingly involved in the care of children with different forms of malignancy, there has not been an emphasis on developing special expertise in this area. The fast pace of discovery in this field, including the development of new therapy protocols with their own kidney side effects and the introduction of the CD19-targeted chimeric antigen receptor T cell (CAR-T) therapy, has introduced new challenges for general pediatric nephrologists because of the unique effects of these treatments on the kidney. Moreover, with the improved outcomes in children receiving cancer therapy come an increased number of survivors at risk for chronic kidney disease related to both their cancer diagnosis and therapy. Therefore, it is time for pediatric onco-nephrology to take its spot on the expanding subspecialties map in pediatric nephrology.

Ifosfamide-induced nephrogenic diabetes insipidus responsive to supraphysiologic doses of intravenous desmopressin

Nephrogenic diabetes insipidus (DI) refers to the reduction in the ability of the kidney to concentrate urine, which can be caused by partial or complete resistance at the site of action of anti-diuretic hormone (ADH) in the collecting tubules. Ifosfamide-induced nephrogenic DI typically occurs concomitantly in patients who have other signs of tubular toxicity consistent with Fanconi syndrome including glucosuria, aminoaciduria, and hypophosphatemia. We present a case of a 36-year-old female with recurrent synovial cell sarcoma of the pleural membranes, treated with ifosfamide-based chemotherapy, who was admitted to the hospital for the management of polyuria, hypotension, as well as electrolyte derangements including hypokalemia, hypophosphatemia and non-anion gap metabolic acidosis, 1 week after receiving a cumulative ifosfamide dose of 7.5 g/m². Nephrogenic DI was indicated by polyuria as well as a urine osmolality to plasma osmolality ratio of less than 1.5 following a trial of intravenous desmopressin, but the patient’s acute kidney injury on presentation precluded the early employment of thiazides and non-steroidal anti-inflammatory drugs (NSAIDs). Instead, the patient’s polyuria and urine osmolality improved only after the administration of repetitive supraphysiologic doses of intravenous desmopressin. Our case reiterates that patients with non-hereditary nephrogenic DI may have partial rather than complete resistance to ADH and highlights that desmopressin may be considered in patients with ifosfamide-induced nephrogenic DI to prevent severe volume depletion, especially in patients who have persistent symptomatic polyuria despite maintaining a careful fluid balance and pharmacological therapy with NSAIDs and diuretics, or if the patient’s clinical condition precludes the use of these strategies.

The safety of current pharmacotherapeutic strategies for osteosarcoma

Introduction: Peri-operative chemotherapy is the backbone of treatment for patients with osteosarcoma. Methotrexate, cisplatinum, doxorubicin and ifosfamide are the main drugs used in chemotherapy regimens used for osteosarcoma.Areas covered: We have reviewed here the relevant literature related to the incidence and management of acute and late toxicities of systemic treatment used for the management of patients with osteosarcoma.Expert opinion: Early diagnosis and appropriate management of acute and late toxicities of chemotherapy is crucial for an efficient care of osteosarcoma patients. Although the incidence and management of chemotherapy-related acute toxicities are well known by most oncologists, the use of high doses of methotrexate have the potential to cause fatal toxicities and, therefore, needs careful monitoring. Moreover, the diagnosis of late toxicities is more challenging and requires long-term follow-up for an appropriate management.

Late Effects After Haematopoietic Stem Cell Transplantation in ALL, Long-Term Follow-Up and Transition: A Step Into Adult Life

Haematopoietic stem cell transplant (HSCT) can be a curative treatment for children and adolescents with very-high-risk acute lymphoblastic leukaemia (ALL). Improvements in supportive care and transplant techniques have led to increasing numbers of long-term survivors worldwide. However, conditioning regimens as well as transplant-related complications are associated with severe sequelae, impacting patients' quality of life. It is widely recognised that paediatric HSCT survivors must have timely access to life-long care and surveillance in order to prevent, ameliorate and manage all possible adverse late effects of HSCT. This is fundamentally important because it can both prevent ill health and optimise the quality and experience of survival following HSCT. Furthermore, it reduces the impact of preventable chronic illness on already under-resourced health services. In addition to late effects, survivors of paediatric ALL also have to deal with unique challenges associated with transition to adult services. In this review, we: (1) provide an overview of the potential late effects following HSCT for ALL in childhood and adolescence; (2) focus on the unique challenges of transition from paediatric care to adult services; and (3) provide a framework for long-term surveillance and medical care for survivors of paediatric ALL who have undergone HSCT.

Oxazaphosphorines combined with immune checkpoint blockers: dose-dependent tuning between immune and cytotoxic effects

Background

Oxazaphosphorines (cyclophosphamide (CPA), ifosfamide (IFO)) are major alkylating agents of polychemotherapy protocols but limiting their toxicity and increasing their efficacy could be of major interest. Oxazaphosphorines are prodrugs that require an activation by cytochrome P450 (CYP). CPA is mainly metabolized (>80%) to phosphoramide mustard while only 10%–50% of IFO is transformed in the alkylating entity, isophosphoramide mustard and 50%–90% of IFO release chloroacetaldehyde, a nephrotoxic and neurotoxic metabolite. Geranyloxy-IFO (G-IFO) was reported as a preactivated IFO to circumvent the toxic pathway giving directly the isophosphoramide mustard without CYP metabolization. The similarity in structure of CPA and IFO and the similarity in metabolic balance of CPA and G-IFO have led us to explore immunomodulatory effect of these components in mice and to investigate the combination of these oxazaphosphorines with immune checkpoint blockers (ICB).

Methods

The investigation of the immunomodulatory properties of IFO and G-IFO compared with CPA has been conducted through immune cell phenotyping by flow cytometry and analysis of the cytokine profile of T cells after ex-vivo restimulation. T cell-mediated antitumor efficacy was confirmed in CD4⁺ and CD8⁺ T cell-depleted mice. A combination of oxazaphosphorines with an anti-programmed cell death 1 (PD-1) antibody has been studied in MCA205 tumor-bearing mice.

Results

Studies on a MCA205 mouse model have demonstrated a dose-dependent effect of IFO and G-IFO on T cell immunity. These components in particular favored Th1 polarization when used at low dose (150 and eq. 100 mg/kg, respectively). Antitumor activity at low dose was abolished in mice depleted in CD4⁺ and CD8⁺ T cells. G-IFO at low dose (eq. 100 mg/kg) in combination with anti-PD-1 antidody showed high synergistic antitumor efficacy compared with IFO.

Conclusion

Oxazaphosphorines are characterized by a dual mechanism of antitumor action; low-dose schedules should be preferred in combination with ICB, and dose escalation was found to have better utility in polychemotherapy protocols where a conventional direct cytotoxic anticancer effect is needed. G-IFO, the novel oxazaphosphorine drug, has shown a better metabolic index compared with IFO as its metabolization gives mainly the alkylating mustard as CPA (and not IFO) and a best potential in combination with ICB.

Renal proximal tubulopathy in an HIV-infected patient treated with tenofovir alafenamide and gentamicin: a case report

Background

The nucleotide reverse transcriptase inhibitor Tenofovir Alafenamide (TAF) is a novel pro-drug of tenofovir (TFV) and possesses a superior renal safety profile compared with tenofovir disoproxil fumerate (TDF). Due to unique pharmacokinetic characteristics, treatment with TAF is not associated with significant renal proximal tubular accumulation of TFV. TAF is associated with a lower risk of acute kidney injury, chronic kidney disease, proteinuria and renal proximal tubular dysfunction than treatment with TDF. No cases of Fanconi syndrome have been reported in clinical trials of TAF. It is unknown whether treatment with TAF can lead to accumulation of TFV in proximal tubular cells and cause nephrotoxicity under certain clinical circumstances.

Case presentation

Here we report the case of a patient on stable TAF-based antiretroviral therapy with for HIV-1 infection who developed proximal tubulopathy when treated with gentamicin for febrile neutropenia in the context of relapsed Hodgkin lymphoma. Eighteen days after commencing chemotherapy for relapsed Hodgkin lymphoma the patient presented to hospital with fevers, hypotension and neutropenia. The patient was commenced on piperacillin, tazobactam and gentamicin. Within 24 h the patient developed marked hypokalaemia and hypophosphataemia requiring intravenous replacement therapy. There was proteinuria, glycosuria and evidence of marked urinary electrolyte wasting, consistent with acute proximal tubular dysfunction. Eleven days after the gentamicin was stopped the serum biochemistry normalised. The urinary electrolyte wasting and proteinuria had improved, and the glycosuria had resolved.

Conclusion

This is the first case report to describe acute renal proximal tubulopathy in an HIV-infected patient treated with TAF and gentamicin. As the number of patients prescribed TAF outside the clinical trial setting increases, so too does the potential for previously unreported drug interactions and adverse events. Clinicians need to be aware of potential unreported adverse drug reactions as the use of TAF becomes increasingly common in clinical practice.

Electrolyte Disorders Induced by Antineoplastic Drugs

The use of antineoplastic drugs has a central role in treatment of patients affected by cancer but is often associated with numerous electrolyte derangements which, in many cases, could represent life-threatening conditions. In fact, while several anti-cancer agents can interfere with kidney function leading to acute kidney injury, proteinuria, and hypertension, in many cases alterations of electrolyte tubular handling and water balance occur. This review summarizes the mechanisms underlying the disturbances of sodium, potassium, magnesium, calcium, and phosphate metabolism during anti-cancer treatment. Platinum compounds are associated with sodium, potassium, and magnesium derangements while alkylating agents and Vinca alkaloids with hyponatremia due to syndrome of inappropriate antidiuretic hormone secretion (SIADH). Novel anti-neoplastic agents, such as targeted therapies (monoclonal antibodies, tyrosine kinase inhibitors, immunomodulators, mammalian target of rapamycin), can induce SIADH-related hyponatremia and, less frequently, urinary sodium loss. The blockade of epidermal growth factor receptor (EGFR) by anti-EGFR antibodies can result in clinically significant magnesium and potassium losses. Finally, the tumor lysis syndrome is associated with hyperphosphatemia, hypocalcemia and hyperkalemia, all of which represent serious complications of chemotherapy. Thus, clinicians should be aware of these side effects of antineoplastic drugs, in order to set out preventive measures and start appropriate treatments.

The growing pains of ifosfamide

Ifosfamide is a commonly used chemotherapeutic known to have numerous adverse kidney manifestations. In this issue of Clinical Kidney Journal, Ensergueix et al. report a multicentric observational retrospective French study on 34 adult patients with tubular dysfunction and /or kidney dysfunction following ifosfamide treatment. Of these patients, 18% had isolated proximal tubular dysfunction, 14% had isolated acute kidney injury (AKI), 18% had isolated chronic kidney disease (CKD) and 50% had a combination of proximal tubular dysfunction and AKI. Concomitant treatment with cisplatin was identified as a risk factor for the development of AKI, and cisplatin and age were associated with estimated glomerular filtration rate at last follow-up. Interestingly, the cumulative dose of ifosfamide was not associated with renal outcomes. This report highlights the need for additional studies on the prevalence, spectrum and management of ifosfamide-associated nephrotoxicity and clearly demonstrates that patients who received ifosfamide should be followed long term to detect proximal tubular dysfunction and CKD early.

Hypertension in Cancer Patients and Survivors: Epidemiology, Diagnosis, and Management

Cancer patients and survivors of cancer have a greater burden of cardiovascular disease compared to the general population. Much of the elevated cardiovascular risk in these individuals is likely attributable to hypertension, as individuals with cancer have a particularly high incidence of hypertension following cancer diagnosis. Treatment with chemotherapy is an independent risk factor for hypertension due to direct effects of many agents on endothelial function, sympathetic activity, and renin-angiotensin system activity as well as nephrotoxicity. Diagnosis and management of hypertension in cancer patients requires accurate blood pressure measurement and consideration of potential confounding factors, such as adjuvant treatments and acute pain, that can temporarily elevate blood pressure readings. Home blood pressure monitoring can be a useful tool to facilitate longitudinal blood pressure monitoring for titration of antihypertensive medications. Selection of antihypertensive agents in cancer patients should account for treatment-specific morbidities and target organ injury.

Discrete Changes in Glucose Metabolism Define Aging

Aging is a physiological process in which multifactorial processes determine a progressive decline. Several alterations contribute to the aging process, including telomere shortening, oxidative stress, deregulated autophagy and epigenetic modifications. In some cases, these alterations are so linked with the aging process that it is possible predict the age of a person on the basis of the modification of one specific pathway, as proposed by Horwath and his aging clock based on DNA methylation. Because the energy metabolism changes are involved in the aging process, in this work, we propose a new aging clock based on the modifications of glucose catabolism. The biochemical analyses were performed on mononuclear cells isolated from peripheral blood, obtained from a healthy population with an age between 5 and 106 years. In particular, we have evaluated the oxidative phosphorylation function and efficiency, the ATP/AMP ratio, the lactate dehydrogenase activity and the malondialdehyde content. Further, based on these biochemical markers, we developed a machine learning-based mathematical model able to predict the age of an individual with a mean absolute error of approximately 9.7 years. This mathematical model represents a new non-invasive tool to evaluate and define the age of individuals and could be used to evaluate the effects of drugs or other treatments on the early aging or the rejuvenation.

Outcomes of pediatric retinoblastoma treated with ICEV regimen: A single-center study

Retinoblastoma is the most common intraocular malignancy in children. The aim of this study was to investigate the efficacy and toxicity of combination ifosfamide, carboplatin, etoposide, and vincristine (ICEV) in advanced-stage pediatric retinoblastoma [International Classification of Retinoblastoma (ICRB) group D or E], and in ICRB group C in the second eye in simultaneously treated bilateral retinoblastoma. The medical records of retinoblastoma patients treated with concurrent ICEV regimen and focal therapy were retrospectively reviewed. The ICEV treatment protocol was, as follows: ifosfamide 1800 mg/m² on Days 1-3; MESNA 600 mg/m² on Days 1-3; carboplatin 560 mg/m² on Day 1; etoposide 150 mg/m² on Days 1-3; and vincristine 1.5 mg/m² on Day 1. Of 16 retinoblastoma patients, 13 had bilateral disease. Seven first eyes in bilateral disease that were enucleated prior to ICEV therapy were excluded. Twenty-two eyes were finally included (six group C, six group D, and ten group E). Median follow-up was 3.4 years, and the median number of ICEV courses was 7. Fifteen globes could be salvaged, 12 responded to ICEV (six group C, five group D, and one group E), and three unresponsive eyes could be salvaged with external beam radiation therapy (EBRT). Enucleation-free and relapse-free survival was 68.2 and 54.5%, respectively. The results of this study suggest ICEV as an alternative therapeutic approach for globe salvage in pediatric retinoblastoma, especially in ICRB groups C and D with manageable acute toxicity. Further study in larger cohort is needed to confirm the effectiveness of treatment.

Partial Fanconi Syndrome Induced by Ifosfamide

Several commonly used chemotherapeutic agents, antibiotics, antivirals, and antiepileptic medications can cause partial or full Fanconi syndrome, disorders which can generally be described as transport defects in the proximal renal tubule, associated with non-anion gap metabolic acidosis. Fanconi syndrome is underreported and therefore often missed in the clinical setting. Herein, we present a case report that details the course of a 64-year-old female with a history of stage IV undifferentiated pleomorphic sarcoma who after her sixth chemotherapeutic cycle (adriamycin, ifosfamide, and mesna) developed severe hypokalemia, hypophosphatemia, and proteinuria without glycosuria, eventually diagnosed with partial Fanconi syndrome. The aim of this report is to highlight the importance of routine serum and urine monitoring in patients undergoing therapy with potentially nephrotoxic agents to avoid potentially fatal renal nephrotoxicity, including partial and full Fanconi syndrome.

Long-term renal follow-up of children treated with cisplatin, carboplatin, or ifosfamide: a pilot study

BACKGROUND

Childhood cancer survivors treated with cisplatin, ifosfamide, or carboplatin are at risk for late kidney and blood pressure (BP) abnormalities. Few studies have comprehensively evaluated kidney outcomes and 24-h ambulatory BP monitoring (ABPM) in this population. We aimed to describe chemotherapy-associated acute kidney injury (AKI) and late kidney outcomes using standardized definitions.

METHODS

This was a single-center longitudinal pilot study of 23 children who participated in a previous study during cisplatin, carboplatin, or ifosfamide treatment. Medical charts were reviewed retrospectively. Available patients were approached for a study visit for blood and urine collection, BP measurement, and ABPM. AKI is defined by serum creatinine (SCr) rise (Kidney Disease: Improving Global Outcomes definition [SCr-AKI]). Electrolyte-AKI is defined by hypokalemia, hypophosphatemia, or hypomagnesemia. Chronic kidney disease (CKD) is defined by estimated glomerular filtration rate < 90 mL/min/1.73 m², albuminuria, or proteinuria. Electrolyte-CKD is defined by low serum electrolyte concentration or electrolyte supplementation.

RESULTS

Median age at chemotherapy start was 8.3 years; 9/23 (39%) were boys. Fourteen out of 23 (61%) patients had SCr-AKI during therapy; all developed electrolyte-AKI. Median 5.7 years post-chemotherapy, 7/22 (32%) had CKD, 11/23 (48%) had electrolyte-CKD, and 2/20 (10%) had hypertension. Fifteen out of 23 patients (65%) had either CKD, electrolyte-CKD, or hypertension. In ten patients available for a study visit (median 4.9 years post-chemotherapy), 1/10 (10%) had hypertension by ABPM; none had masked or white coat hypertension. All ten had at least one kidney abnormality (CKD, electrolyte-CKD, office pre-hypertension, or abnormal ABPM).

CONCLUSIONS

Using standardized outcome definitions, children treated with cisplatin, carboplatin, or ifosfamide have a high prevalence of late kidney abnormalities. Research must elucidate best practice for post-cancer treatment follow-up and kidney complication treatment.

Long-term renal function and hypertension in adult survivors of childhood sarcoma: Single center experience

AIM

Little data is available on long-term renal impairment in survivors from childhood sarcoma. We investigated the prevalence of renal impairment and hypertension after very long-term follow-up in survivors who reached adulthood after treatment for childhood sarcoma.

METHODS

A cross-sectional single center study was performed. Outcomes included estimating glomerular filtration rate (eGFR), albuminuria, glycosuria, serum phosphate and magnesium, tubular reabsorption phosphate (TRP), chronic kidney disease (CKD) according to the "Kidney Disease: Improving Global Outcomes" (KDIGO) guidelines and blood pressure (BP).

RESULTS

Out of 87 > 5-year sarcoma survivors, 30 adults (10F/20M, median age at diagnosis 9 years, median age at investigation 26 years, median follow-up 16 years, mean 19 years) were identified. Renal impairment was detected in four cases (13.3%); three of these fulfilled the criteria for CKD. Among the adult survivors, a subgroup of 15 cases (50%) had received ifosfamide without confounding factors such as a diagnosis of genito-urinary rhabdomyosarcoma or administration of other potentially nephrotoxic chemotherapy (platinum-based drugs or methotrexate); no renal dysfunction was detected in this subgroup. In the whole cohort of sarcoma survivors, hypertension was diagnosed in four cases (13.3%); BP was significantly correlated with body mass index [p .014].

CONCLUSION

In our series of adult survivors treated for a diagnosis of sarcoma in their childhood, the prevalence of CKD was 10%. We found survivors treated with ifosfamide as the only nephrotoxic agent did not present glomerular or tubular toxicity at long term follow-up, but further studies including a larger number of cases are required to confirm it.

Position paper: Rationale for the treatment of children with CCSK in the UMBRELLA SIOP-RTSG 2016 protocol

The International Society of Paediatric Oncology-Renal Tumour Study Group (SIOP-RTSG) has developed a new protocol for the diagnosis, treatment, and follow-up monitoring of childhood renal tumours - the UMBRELLA SIOP-RTSG 2016 protocol (the UMBRELLA protocol). This protocol has been designed to continue international collaboration in the treatment of childhood renal tumours and will be implemented in over 50 different countries. Clear cell sarcoma of the kidney, which is a rare paediatric renal tumour that most commonly occurs in children between 2 and 4 years of age, is specifically addressed in the UMBRELLA protocol.

Late renal toxicity of treatment for childhood malignancy: risk factors, long-term outcomes, and surveillance

Chronic glomerular and tubular nephrotoxicity is reported in 20-50% and 20-25%, respectively, of children and adolescents treated with ifosfamide and 60-80% and 10-30%, respectively, of those given cisplatin. Up to 20% of children display evidence of chronic glomerular damage after unilateral nephrectomy for a renal tumour. Overall, childhood cancer survivors have a ninefold higher risk of developing renal failure compared with their siblings. Such chronic nephrotoxicity may have multiple causes, including chemotherapy, radiotherapy exposure to kidneys, renal surgery, supportive care drugs and tumour-related factors. These cause a wide range of chronic glomerular and tubular toxicities, often with potentially severe clinical sequelae. Many risk factors for developing nephrotoxicity, mostly patient and treatment related, have been described, but we remain unable to predict all episodes of renal damage. This implies that other factors may be involved, such as genetic polymorphisms influencing drug metabolism. Although our knowledge of the long-term outcomes of chronic nephrotoxicity is increasing, there is still much to learn, including how we can optimally predict or achieve early detection of nephrotoxicity. Greater understanding of the pathogenesis of nephrotoxicity is needed before its occurrence can be prevented.

The 6R's of drug induced nephrotoxicity

Drug induced kidney injury is a frequent adverse event which contributes to morbidity and increased healthcare utilization. Our current knowledge of drug induced kidney disease is limited due to varying definitions of kidney injury, incomplete assessment of concurrent risk factors and lack of long term outcome reporting. Electronic surveillance presents a powerful tool to identify susceptible populations, improve recognition of events and provide decision support on preventative strategies or early intervention in the case of injury. Research in the area of biomarkers for detecting kidney injury and genetic predisposition for this adverse event will enhance detection of injury, identify those susceptible to injury and likely mitigate risk. In this review we will present a 6R framework to identify and mange drug induced kidney injury – risk, recognition, response, renal support, rehabilitation and research.

Late effects of chemotherapeutic agents on renal function in childhood cancer survivors: a review of the literature

BACKGROUND

Survival outcomes for childhood cancers have significantly improved. As more children are now surviving into adulthood, knowledge of the long-term effects of childhood cancer treatments has become the focus of research.

AIM

To determine what is known about the incidence of renal function impairment in childhood cancer survivors and to determine what is known about risk factors for developing renal function impairment following childhood cancer treatment.

METHODS

A comprehensive literature search was preformed to identify studies that investigated renal dysfunction in patients who were diagnosed with childhood cancer and treated with potentially nephrotoxic chemotherapeutic agents. Potentially nephrotoxic chemotherapeutic agents identified in the selection criteria include ifosfamide, cisplatin, carboplatin and methotrexate.

RESULTS

15 papers met the inclusion criteria. Renal function impairment was reported in 15 of 15 studies included in this literature review. The incidence of ifosfamide induced nephrotoxicity varied from 1 to 50 %. This variation may be due to the heterogeneity of reported outcome measurements. Treatment with cisplatin and carboplatin was associated with hypomagnesemia. The prevalence of hypomagnesemia varied from 7 to 29 %. This variation may be due to diversity of treatment protocols. The incidence of renal dysfunction following treatment with methotrexate was reported as 1.8 % and completely reversible.

CONCLUSION

As more childhood cancer survivors are reaching adulthood, a new niche of cancer research has emerged. Researchers are now investigating the late effects due to cytotoxic treatments. Renal function impairment is a potential late effect of treatment with nephrotoxic chemotherapeutic agents including ifosfamide, cisplatin, carboplatin and methotrexate.

Yield of Urinalysis Screening in Pediatric Cancer Survivors

BACKGROUND

The Children's Oncology Group (COG) publishes consensus guidelines with screening recommendations for early identification of treatment-related morbidities among childhood cancer survivors. We sought to estimate the yield of recommended yearly urinalysis screening for genitourinary complications as per Version 3.0 of the COG Long-Term Follow-Up Guidelines and identify possible risk factors for abnormal screening in a survivor population.

PROCEDURE

A database of pediatric cancer survivors evaluated between January 2008 and March 2012 at Children's Healthcare of Atlanta was queried for survivors at risk for genitourinary late effects. The frequency of abnormal urinalyses (protein ≥1+ and/or presence of glucose and/or ≥5 red blood cells per high power field) was estimated. Risk factors associated with abnormal screening were identified.

RESULTS

Chart review identified 773 survivors (57% male; 67% Caucasian; 60% leukemia/lymphoma survivors; mean age at diagnosis, 5.7 years [range: birth to 17.7 years]; time from diagnosis to initial screening, 7.6 years [range: 2.3 to 21.5 years]) who underwent urinalysis. Abnormal results were found in 78 (5.3%) of 1,484 total urinalyses. Multivariable analysis revealed higher dose ifosfamide (odds ratio [OR] = 6.8, 95% confidence interval [CI] 2.9-16.0) and total body irradiation (TBI, OR = 3.0, 95% CI 1.0-8.4) as significant risk factors for abnormal initial urinalysis screening.

CONCLUSIONS

Pediatric cancer survivors exposed to higher dose ifosfamide or TBI may be at higher risk of abnormal findings on urinalysis screening. Targeted screening of these higher risk patients should be considered.

Aminoaciduria in the prediction of ifosfamide-induced tubulopathy after childhood cancer: a feasibility study

BACKGROUND

Ifosfamide, an alkylating agent used widely in the treatment of childhood malignancy, can cause many side effects including a proximal tubulopathy. Studies suggest that aminoaciduria is seen most commonly of all the biochemical abnormalities of ifosfamide-induced tubulopathy. A recent systematic review has found a paucity of data regarding the value of early markers indicating clinically significant tubulopathy. We undertook a pilot study to determine the feasibility of examining whether patients can be risk-stratified on the basis of aminoaciduria for the development of future significant ifosfamide-induced tubulopathy, to allow the evolution of appropriate follow-up strategies. We also aimed to define accrual rates, costs and clinical demands for a future larger study.

METHODS

This observational study recruited 21 patients from the Leeds Paediatric Oncology service. The medical notes of each patient were reviewed for demographic and clinical data. Simultaneous samples of blood and urine were obtained.

RESULTS

The investigations in the feasibility study were acceptable to patients and were minimally demanding on both clinical and laboratory staff. Financially, the cost per patient was minimal. This study was not powered to detect significant associations with TmP/GFR (ratio of renal tubular maximum reabsorption rate of phosphate to glomerular filtration rate), growth and electrolyte supplementation. However, all patients with minimal aminoaciduria (≤2 elevated urinary amino acids) had normal TmP/GFR and no need for electrolyte supplementation.

CONCLUSIONS

This pilot study has shown that a larger study is feasible and may provide clinically useful data to change current practice. This should aim to establish whether the number of abnormal amino acids or the degree of abnormality is most significant in predicting clinically significant proximal tubulopathy.

Effect of Kidney Function on Drug Kinetics and Dosing in Neonates, Infants, and Children

Neonates, infants, and children differ from adults in many aspects, not just in age, weight, and body composition. Growth, maturation and environmental factors affect drug kinetics, response and dosing in pediatric patients. Almost 80% of drugs have not been studied in children, and dosing of these drugs is derived from adult doses by adjusting for body weight/size. As developmental and maturational changes are complex processes, such simplified methods may result in subtherapeutic effects or adverse events. Kidney function is impaired during the first 2 years of life as a result of normal growth and development. Reduced kidney function during childhood has an impact not only on renal clearance but also on absorption, distribution, metabolism and nonrenal clearance of drugs. 'Omics'-based technologies, such as proteomics and metabolomics, can be leveraged to uncover novel markers for kidney function during normal development, acute kidney injury, and chronic diseases. Pharmacometric modeling and simulation can be applied to simplify the design of pediatric investigations, characterize the effects of kidney function on drug exposure and response, and fine-tune dosing in pediatric patients, especially in those with impaired kidney function. One case study of amikacin dosing in neonates with reduced kidney function is presented. Collaborative efforts between clinicians and scientists in academia, industry, and regulatory agencies are required to evaluate new renal biomarkers, collect and share prospective pharmacokinetic, genetic and clinical data, build integrated pharmacometric models for key drugs, optimize and standardize dosing strategies, develop bedside decision tools, and enhance labels of drugs utilized in neonates, infants, and children.

Drug-induced acid-base disorders

The incidence of acid-base disorders (ABDs) is high, especially in hospitalized patients. ABDs are often indicators for severe systemic disorders. In everyday clinical practice, analysis of ABDs must be performed in a standardized manner. Highly sensitive diagnostic tools to distinguish the various ABDs include the anion gap and the serum osmolar gap. Drug-induced ABDs can be classified into five different categories in terms of their pathophysiology: (1) metabolic acidosis caused by acid overload, which may occur through accumulation of acids by endogenous (e.g., lactic acidosis by biguanides, propofol-related syndrome) or exogenous (e.g., glycol-dependant drugs, such as diazepam or salicylates) mechanisms or by decreased renal acid excretion (e.g., distal renal tubular acidosis by amphotericin B, nonsteroidal anti-inflammatory drugs, vitamin D); (2) base loss: proximal renal tubular acidosis by drugs (e.g., ifosfamide, aminoglycosides, carbonic anhydrase inhibitors, antiretrovirals, oxaliplatin or cisplatin) in the context of Fanconi syndrome; (3) alkalosis resulting from acid and/or chloride loss by renal (e.g., diuretics, penicillins, aminoglycosides) or extrarenal (e.g., laxative drugs) mechanisms; (4) exogenous bicarbonate loads: milk-alkali syndrome, overshoot alkalosis after bicarbonate therapy or citrate administration; and (5) respiratory acidosis or alkalosis resulting from drug-induced depression of the respiratory center or neuromuscular impairment (e.g., anesthetics, sedatives) or hyperventilation (e.g., salicylates, epinephrine, nicotine).

Drug-induced acute kidney injury in children

Acute kidney injury (AKI) is a serious problem occurring in anywhere between 8 and 30% of children in the intensive care unit. Up to 25% of these cases are believed to be the result of pharmacotherapy. In this review we have focused on several relevant drugs and/or drug classes, which are known to cause AKI in children, including cancer chemotherapeutics, non-steroidal anti-inflammatory drugs and antimicrobials. AKI demonstrates a steady association with increased long term risk of poor outcomes including chronic kidney disease and death as determined by the extent of injury. For this reason it is important to understand the causality and implications of these drugs and drug classes. Children occupy a unique patient population, advocating the importance of understanding how they are affected dissimilarly compared with adults. While the kidney itself is likely more susceptible to injury than other organs, the inherent toxicity of these drugs also plays a major role in the resulting AKI. Mechanisms involved in the toxicity of these drugs include oxidative damage, hypersensitivity reactions, altered haemodynamics and tubule obstruction and may affect the glomerulus and/or the tubules. Understanding these mechanisms is critical in determining the most effective strategies for treatment and/or prevention, whether these strategies are less toxic versions of the same drugs or add-on agents to mitigate the toxic effect of the existing therapy.

Ifosfamide induced renal rickets

Ifosfamide is commonly used as a chemotherapeutic agent in children. The authors report a 4-y-old boy who developed proximal renal tubulopathy with florid rickets a year after completion of ifosfamide therapy for Ewing's sarcoma. After initiation of treatment, there was complete healing of rickets and he did not need supplements beyond 18 mo. Growth monitoring and musculoskeletal system examination is important in all children who have received ifosfamide therapy. Routine monitoring for nephrotoxicity during and after ifosfamide therapy helps in early identification and intervention.

Improvement in karyomegalic interstitial nephritis three years after ifosfamide and cisplatin therapy by corticosteroid

Long-term nephrotoxicity of ifosfamide is occasionally progressive, and, in such case, there has been no specific treatment to prevent progression. It has been reported that the presence of karyomegalic interstitial nephritis, which is rare type of interstitial nephritis, may be related to ifosfamide-induced nephropathy with poor prognosis and resistant to the immunosuppressive therapy. A 15-year-old boy presented with progressive nephrotoxicity 3 years after systemic chemotherapy with ifosfamide and cisplatin for the treatment of osteosarcoma. Renal biopsy revealed the severe tubulointerstitial nephritis with tubular atrophy and focal global and segmental glomerular sclerosis. It also showed tubular epithelial cells with variably sized nuclei, some of which were massively enlarged, abnormal hyperchromatic, irregular shaped, and bizarre-appearing. These morphological changes were suggestive of the histology of karyomegalic interstitial nephritis. Corticosteroid retarded the progression of nephrotoxicity. The present case is the first report, suggesting that corticosteroid was effective against the late-onset renal toxicity by ifosfamide therapy. Our case also suggests that karyomegalic interstitial nephritis may be the result of long-term nephrotoxicity of ifosfamide. Since concurrent treatment with cisplatin is one of the risk factors for ifosfamide nephrotoxicity, there is a possibility that cisplatin may have a synergetic effect with ifosfamide for producing karyomegalic interstitial nephritis.

Interleukin 18 as a marker of chronic nephropathy in children after anticancer treatment

Novel markers of nephrotoxicity, including kidney injury molecule 1 (KIM-1), interleukin 18 (IL-18), and beta-2 microglobulin, were used in the detection of acute renal injury. The aim of the study was to establish the frequency of postchemotherapy chronic kidney dysfunction in children and to assess the efficacy of IL-18, KIM-1, and beta-2 microglobulin in the detection of chronic nephropathy. We examined eighty-five patients after chemotherapy (median age of twelve years). The median age at the point of diagnosis was 4.2 years, and the median follow-up time was 4.6 years. We performed classic laboratory tests assessing kidney function and compared the results with novel markers (KIM-1, beta-2 microglobulin, and IL-18). Features of subclinical renal injury were identified in forty-eight children (56.3% of the examined group). Nephropathy, especially tubulopathy, appeared more frequently in patients treated with ifosfamide, cisplatin, and/or carboplatin, following nephrectomy or abdominal radiotherapy (P = 0.14, P = 0.11, and P = 0.08, resp.). Concentrations of IL-18 and beta-2 microglobulin were comparable with classic signs of tubulopathy (P = 0.0001 and P = 0.05). Concentrations of IL-18 were also significantly higher in children treated with highly nephrotoxic drugs (P = 0.0004) following nephrectomy (P = 0.0007) and abdominal radiotherapy (P = 0.01). Concentrations of beta-2 microglobulin were higher after highly toxic chemotherapy (P = 0.004) and after radiotherapy (P = 0.02). ROC curves created utilizing IL-18 data allowed us to distinguish between children with nephropathy (value 28.8 pg/mL) and tubulopathy (37.1 pg/mL). Beta-2 microglobulin and IL-18 seem to be promising markers of chronic renal injury in children after chemotherapy.

Long-term nephrotoxicity in adult survivors of childhood cancer

BACKGROUND AND OBJECTIVES

Because little is known about long-term treatment-related nephrotoxicity, the aim was to determine risk factors for renal impairment long after childhood cancer treatment.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Data from 763 adult childhood cancer survivors (414 men) were obtained during regular visits at the late-effects clinic between 2003 and 2009. Median follow-up time was 18.3 years (range=5.0-58.2). Glomerular function was assessed by estimated GFR (using the Modification of Diet in Renal Disease formula), urinary albumin creatinine ratio, and tubular function by urinary β2-microglobulin creatinine ratio. The association with treatment factors was analyzed with covariance analysis for estimated GFR and logistic regression for urinary albumin and urinary β2-microglobulin creatinine ratios.

RESULTS

Survivors treated with nephrectomy and abdominal irradiation had significantly lower estimated GFR than survivors not treated with nephrectomy/abdominal irradiation (estimated mean=90 ml/min per 1.73 m(2) versus 106, P<0.001). Estimated GFR was significantly lower in survivors after treatment with high-dose ifosfamide (88 versus 98, P=0.02) and high-dose cisplatin (83 versus 101, P=0.004) compared with survivors not treated with these regimen. Nephrectomy combined with abdominal radiotherapy (odds ratio=3.14, 95% confidence interval=1.02; 9.69) and high-dose cisplatin (odds ratio=5.19, 95% confidence interval=1.21; 22.21) was associated with albuminuria. High-dose ifosfamide (odds ratio=6.19, 95% confidence interval=2.45; 15.67) was associated with increased urinary β2-microglobulin creatinine ratio. Hypertension was present in 23.4% of survivors and 31.4% of renal tumor survivors.

CONCLUSIONS

Treatment with unilateral nephrectomy, abdominal radiotherapy, cisplatin, and ifosfamide was associated with lower estimated GFR. Persisting tubular damage was related to ifosfamide treatment.

Renal dysfunction and elevated blood pressure in long-term childhood cancer survivors

BACKGROUND AND OBJECTIVES

Little is known about renal function and blood pressure (BP) in long-term childhood cancer survivors. This cross-sectional study evaluated prevalence of these outcomes and associated risk factors in long-term childhood cancer survivors at their first visit to a specialized outpatient clinic.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Estimated GFR; percentages of patients with albuminuria, hypomagnesemia, and hypophosphatemia; and BP were assessed in 1442 survivors ≥5 years after diagnosis. Multivariable logistic regression analyses were used to estimate effect of chemotherapy, nephrectomy, and radiation therapy on the different outcomes.

RESULTS

At a median age of 19.3 years (interquartile range, 15.6-24.5 years), 28.1% of all survivors had at least one renal adverse effect or elevated BP. The median time since cancer diagnosis was 12.1 years (interquartile range, 7.8-17.5 years). High BP and albuminuria were most prevalent, at 14.8% and 14.5%, respectively. Sixty-two survivors (4.5%) had an estimated GFR <90 ml/min per 1.73 m(2). Survivors who had undergone nephrectomy had the highest risk for diminished renal function (odds ratio, 8.6; 95% confidence interval [CI], 3.4-21.4). Combined radiation therapy and nephrectomy increased the odds of having elevated BP (odds ratio, 4.92; 95% CI, 2.63-9.19), as did male sex, higher body mass index, and longer time since cancer treatment.

CONCLUSION

Almost 30% of survivors had renal adverse effects or high BP. Therefore, monitoring of renal function in high-risk groups and BP in all survivors may help clinicians detect health problems at an early stage and initiate timely therapy to prevent additional damage.

Renal tumours: long-term outcome

Childhood cancer is rare, with an incidence of 100 new cases per million children and with renal tumours contributing 7% of cases. The introduction of multimodality treatment, surgery, radiotherapy and chemotherapy, has led to an exponential increase in the 5-year survival rate to >80%. However, this successful treatment has led to the development of late adverse effects. These treatment-related effects can cause premature deaths and increased morbidity compared with patients' peers. Radiation causes damage to tissue and organs within the radiation field, affecting growth and function, and is largely responsible for the leading cause of death, namely, second malignant neoplasms. Another important late effect is cardiac dysfunction due to anthracycline use with or without cardiac radiation. In addition, a few patients have genetic abnormalities predisposing to Wilms tumour development, which result in renal dysfunction in the long term and may be exacerbated by cancer treatment regimens. Awareness of late consequences of cancer treatment is important, as early recognition can improve outcome. When presented with a patient with a history of renal tumours, it is vital to enquire about previous treatment to understand whether it is relevant to the presenting problem.

Ifosfamide induced Fanconi syndrome

Ifosfamide (IFA) is a powerful chemotherapeutic drug that is active against a variety of paediatric malignancies. However, renal toxicities such as haemorrhagic cystitis and Fanconi syndrome are major hazards that hinder its use in clinical practice. The authors present a case of a patient treated for Wilms' tumour with IFA who developed rickets with Fanconi syndrome. Patients undergoing IFA treatment must be carefully monitored for the development of iatrogenic complications. Recent studies have improved our understanding of the underlying pathomechanism of IFA induced Fanconi syndrome, and selective renal protection against during chemotherapy with IFA may be possible soon.

Osteomalacia as a late metabolic complication of Ifosfamide chemotherapy in young adults: illustrative cases and review of the literature

Purpose. Ifosfamide is a drug commonly used in the management of sarcomas and other solid tumours. One potential toxicity of its use is renal tubular damage, which can lead to skeletal abnormalities; rickets in children and osteomalacia in adults. We aimed to characterise this rare complication in adults. Patients. Three illustrative patient cases treated in our institution are presented. All were treated for sarcoma, and received varying doses of ifosfamide during their therapy. Methods. We performed a review of the literature on the renal tubular and skeletal complications of ifosfamide in adults. Papers were identified by searches of PubMed using the terms "osteomalacia," "nephrotoxicity," "Fanconi syndrome," "ifosfamide," and "chemotherapy" for articles published between 1970 and 2006. Additional papers were identified from review of references of relevant articles. Results. There are only four case reports of skeletal toxicity secondary to ifosfamide in adults; the majority of data refer to children. Risk factors for development of renal tubular dysfunction and osteodystrophy include platinum chemotherapy, increasing cumulative ifosfamide dose, and reduced nephron mass. The natural history of ifosfamide-induced renal damage is variable, dysfunction may not become apparent until some months after treatment, and may improve or worsen with time. Discussion. Ifosfamide-induced osteomalacia is seldom described in adults. Clinicians should be vigilant for its development, as timely intervention may minimise complications.

Karyomegalic-like nephropathy, Ewing's sarcoma and ifosfamide therapy

Karyomegalic interstitial nephropathy has been reported as a rare interstitial nephritis in adult patients. Histology shows atypical epithelial cells and large abnormal hyperchromatic nuclei with irregular outlines. We report 3 adolescent patients who all recovered from their initial treatment for Ewing's sarcoma but developed a tubulopathy attributed to ifosfamide therapy. Renal impairment resulted in biopsy, which showed features of karyomegalic nephropathy in all 3. One patient has progressed to haemodialysis. Recognition of the pathology may be important in similar patients. It is surmised that the unusual histological findings in these patients stem from a common pathogenesis which may be related to chemotherapeutic agent related nuclear damage. At present there is no specific treatment to prevent progressive renal impairment.

Nephrotoxicity of cancer treatment in children

Chronic renal impairment in children with cancer may be caused by the malignant process itself or result from adverse effects of treatment including cytotoxic drugs, radiotherapy, surgery or supportive treatment. Although severe renal chronic disease is uncommon, occurring in only 0.8% of long-term survivors of childhood cancer, 1.9% of all cases of established renal failure are due to malignancy and 0.8% to drug nephrotoxicity. The relative risk of severe renal chronic disease (compared with siblings) is 8.1, and that of renal failure or the need for dialysis is 8.9. The cytotoxic drugs most likely to cause important chronic nephrotoxicity are ifosfamide and cisplatin, both of which are used widely in many solid tumors and may cause chronic glomerular and/or renal tubular toxicity in 30–60% of treated children. Significant renal toxicity is less frequent with other chemotherapeutic drugs, but may result from treatment with carboplatin, methotrexate and nitrosoureas. Other cytotoxic drugs occasionally cause specific patterns of glomerular or tubular toxicity in children. Partial or unilateral nephrectomy leads to hypertrophy and hyperfiltration of the remaining renal tissue, and may result in microalbuminuria, hypertension and in rare cases, chronic renal impairment. Radiotherapy to a field including renal tissue may cause late onset chronic renal damage, manifest by hematuria, proteinuria, hypertension and anemia, sometimes progressing to chronic renal failure. Chronic nephrotoxicity is also common in survivors of hemopoietic stem cell transplantation, and is often multifactorial with contributions from prior chemotherapy, total body irradiation, immunosuppressive drugs and transplant complications, such as infection or hemorrhage. Patients at risk of renal damage should be monitored regularly with a defined surveillance protocol to enable timely management. General measures often employed to prevent or reduce nephrotoxicity include the use of intravenous hydration during drug administration and avoidance of known risk factors, such as high drug doses. Although numerous potentially nephroprotective drugs have been suggested and investigated, none have yet been introduced into clinical use in children due to the lack of proven efficacy. Improved understanding of the pathogenesis of nephrotoxicity is necessary to reduce the frequency and severity of this potentially serious complication of treatment in children with cancer.

Advances in urinary proteome analysis and biomarker discovery in pediatric renal disease

Recent progress in proteomic analysis and strategies for the identification of clinically useful biomarkers in biofluids has led to the identification of urine as an excellent non-invasive reservoir for biomarkers of disease. Urinary biomarkers have been identified and validated on independent cohorts in different high-incidence adult renal diseases, including diabetic nephropathy, chronic kidney disease and immunoglobulin A-nephropathy, but also in extrarenal disease, such as coronary artery disease. Unfortunately, this type of research is underrepresented in the pediatric population. Here, we present the rare studies in the pediatric population that identified potential clinically useful urinary biomarkers in ureteropelvic junction (UPJ) obstruction and renal Fanconi syndrome. These studies, although limited in number, clearly show the potential of urinary proteomics, especially in the pediatric population. It is anticipated that the advances made in the adult population, the lessons learned on the use of appropriate statistics and the inclusion of independent blinded validation cohorts in these types of studies will rapidly lead to clinical useful urinary biomarkers for other pediatric (renal) disease in a population where non-invasive analysis is particularly appreciated.