A comparative study of size and function of the remnant kidney in patients nephrectomized in childhood for Wilms' tumor and hydronephrosis

Kidney injury rates after unilateral nephrectomy in childhood-a systematic review and meta-analysis

BACKGROUND

Unilateral nephrectomy is a relatively common procedure in children which results in a solitary functioning kidney (SFK). Living with an SFK predisposes to kidney injury, but it remains unknown which children are most at risk. We aimed to investigate kidney injury rates in patients who underwent unilateral nephrectomy in childhood and to investigate differences among nephrectomies performed for a congenital anomaly, malignancy or other condition.

METHODS

MEDLINE and EMBASE were searched for studies reporting kidney injury rates [i.e. proteinuria, hypertension and/or a decreased glomerular filtration rate (GFR)] of patients who underwent unilateral nephrectomy during childhood. Studies including five or more patients with at least 12 months of follow-up were eligible. Analyses were performed using random effects models and stratified by indication for nephrectomy. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and Meta-analysis Of Observational Studies in Epidemiology (MOOSE) guidelines were used for reporting.

RESULTS

Over 5000 unique articles were screened, of which 53 studies reporting on >4000 patients were included in the analyses. Proteinuria, hypertension and a decreased GFR were present in 15.3, 14.5 and 11.9% of patients, respectively. Heterogeneity among the studies was large in several subgroups, impairing quantitative meta-analyses. However, none of our analyses indicated differences in injury rates between a congenital anomaly or malignancy as an indication for nephrectomy.

CONCLUSIONS

Unilateral nephrectomy during childhood results in signs of kidney injury in >10% of patients, with no clear difference between the indications for nephrectomy. Therefore, structured follow-up is necessary in all children who underwent nephrectomy, regardless of the indication.

Towards adulthood with a solitary kidney

Around 1/1000 people have a solitary kidney. Congenital conditions mainly include multicystic dysplastic kidney and unilateral renal aplasia/agenesis; acquired conditions are secondary to nephrectomy performed because of urologic structural abnormalities, severe parenchymal infection, renal trauma, and renal or pararenal tumors. Children born with congenital solitary kidney have a better long-term glomerular filtration rate than those with solitary kidney secondary to nephrectomy later in life. Acute and chronic adaptation processes lead to hyperfiltration followed by fibrosis in the remnant kidney, with further risk of albuminuria, arterial hypertension, and impaired renal function. Protective measures rely on non-pharmacological renoprotection (controlled protein and sodium intake, avoidance/limitation of nephrotoxic agents, keeping normal body mass index, and limitation of tobacco exposure). Lifelong monitoring should include blood pressure and albuminuria assessment, completed by glomerular filtration rate (GFR) estimation in case of abnormal values. In the absence of additional risk factors to solitary kidney, such assessment can be proposed every 5 years. There is no current consensus for indication and timing of pharmacological intervention.

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.

Nephron number, hypertension, and CKD: physiological and genetic insight from humans and animal models

The kidneys play a vital role in the excretion of waste products and the regulation of electrolytes, maintenance of acid-base balance, regulation of blood pressure, and production of several hormones. Any alteration in the structure of the nephron (basic functional unit of the kidney) can have a major impact on the kidney's ability to work efficiently. Progressive decline in kidney function can lead to serious illness and ultimately death if not treated by dialysis or transplantation. While there have been numerous studies that implicate lower nephron numbers as being an important factor in influencing susceptibility to developing hypertension and chronic kidney disease, a direct association has been difficult to establish because of three main limitations: 1) the large variation in nephron number observed in the human population; 2) no established reliable noninvasive methods to determine nephron complement; and 3) to date, nephron measurements have been done after death, which doesn't adequately account for potential loss of nephrons with age or disease. In this review, we will provide an overview of kidney structure/function, discuss the current literature for both humans and other species linking nephron deficiency and cardio-renal complications, as well as describe the major molecular signaling factors involved in nephrogenesis that modulate variation in nephron number. As more detailed knowledge about the molecular determinants of nephron development and the role of nephron endowment in the cardio-renal system is obtained, it will hopefully provide clinicians the ability to accurately identify people at risk to develop CKD/hypertension and lead to a shift in patient care from disease treatment to prevention.

Long-term renal function in unilateral non-syndromic renal tumor survivors treated according to International Society of Pediatric Oncology protocols

BACKGROUND

The risk of renal impairment among survivors of childhood unilateral non-syndromic renal tumors (RTs) is not well defined. We evaluated the prevalence of and possible risk factors for renal impairment by estimating Glomerular Filtration Rate (eGFR) categories and chronic kidney disease (CKD) according to Kidney Disease: Improving Global Outcomes guidelines.

PROCEDURE

Since 1978, 82 patients were treated for RT, according to the International Society of Pediatric Oncology protocols in a single oncology unit. Of the 67 survivors, those who underwent nephron sparing surgery, those with short-term follow-up or those who had bilateral and/or syndromic disease or a second malignancy were excluded. Thirty-five adult survivors (14 M/21F; mean age 25 years; mean follow-up 20 years) were studied by chemistry, kidney ultrasound, blood pressure measurement, urinanalysis. Correlations were investigated between the prevalence of eGFR categories and CKD and gender, age at diagnosis, radiotherapy, chemotherapy, body mass index, time of follow-up, and age at study.

RESULTS

Eight (22.9%) survivors presented a mildly decreased eGFR (G2 category), the mean value was 80 ± 9.78 ml/min/1.73m(2) (median 84.5, range 63-89). Three (8.6%) survivors had CKD and a fourth (2.9%) hypertension. No significant correlations between G2 category and clinical variables were found.

CONCLUSIONS

A small percentage of survivors had CKD or hypertension after two decades. It is not yet clear whether a mildly decreased eGFR that does not constitute CKD in the absence of other markers (albuminuria and/or kidney ultrasound abnormalities) is likely to progress to CKD. Health promotion programs to avoid comorbidities are required.

Function and size of the residual kidney after treatment of Wilms tumor

Long-term damage to the residual kidney is of concern in the survivors of Wilms tumor. Our objective was to evaluate the long-term glomerular function and size of the residual kidney in these patients. Twenty-nine survivors of Wilms tumor diagnosed between July 1999 and June 2004 were enrolled. The glomerular function was assessed by creatinine clearance, 99mTc DTPA radionuclide scintigraphy and 24-hour urinary protein. Renal size was evaluated by ultrasonography. Median age at diagnosis and at enrollment were 2.87 ± 1.8 (range: 0.5-7.5) and 7.9 ± 3.8 years (range: 2.5-18). Median duration of follow-up was 4.78 ± 2.6 years (range: 1-8.8). Evidence of renal dysfunction in the form of either function or size was identified in eight (27.6%) children. Six children had subnormal glomerular filtration rate and one had proteinuria. Subnormal size of the residual kidney was observed in one child. Age at diagnosis, stage, and duration elapsed after nephrectomy had no association with renal dysfunction (P >.05). Long-term follow up is crucial to identify clinical nephrotoxicity among survivors of Wilms tumor.

Nephron Deficiency and Predisposition to Renal Injury in a Novel One-Kidney Genetic Model

Some studies have reported up to 40% of patients born with a single kidney develop hypertension, proteinuria, and in some cases renal failure. The increased susceptibility to renal injury may be due, in part, to reduced nephron numbers. Notably, children who undergo nephrectomy or adults who serve as kidney donors exhibit little difference in renal function compared with persons who have two kidneys. However, the difference in risk between being born with a single kidney versus being born with two kidneys and then undergoing nephrectomy are unclear. Animal models used previously to investigate this question are not ideal because they require invasive methods to model congenital solitary kidney. In this study, we describe a new genetic animal model, the heterogeneous stock-derived model of unilateral renal agenesis (HSRA) rat, which demonstrates 50%-75% spontaneous incidence of a single kidney. The HSRA model is characterized by reduced nephron number (more than would be expected by loss of one kidney), early kidney/glomerular hypertrophy, and progressive renal injury, which culminates in reduced renal function. Long-term studies of temporal relationships among BP, renal hemodynamics, and renal function demonstrate that spontaneous single-kidney HSRA rats are more likely than uninephrectomized normal littermates to exhibit renal impairment because of the combination of reduced nephron numbers and prolonged exposure to renal compensatory mechanisms (i.e., hyperfiltration). Future studies with this novel animal model may provide additional insight into the genetic contributions to kidney development and agenesis and the factors influencing susceptibility to renal injury in individuals with congenital solitary kidney.

Growth and function in childhood of a normal solitary kidney from birth or from early infancy

BACKGROUND

Children with a solitary kidney (SK) have an increased long-term risk of hypertension, albuminuria and glomerulosclerosis. In this study, we assessed the early signs of impaired glomerular filtration in children with a SK from birth or from early infancy.

METHODS

Renal growth and function at ages 4-15.5 years were studied in 38 children with SK and 40 matched control subjects in terms of accelerated growth.

RESULTS

The systolic/diastolic blood pressure Z-scores (p = 0.01/<0.05) and the resistance index (RI) of the arcuate arteries (p = 0.05) were higher in the children with SK. Creatinine clearance and 24-h protein and albumin urinary excretion showed no difference. All but seven children with SK had 99mTc diethylene-triamine pentaacetic acid glomerular filtration rate values of >80 ml/min/1.73 m(2). An independent positive correlation was found between length of the follow-up time and 24-h albumin urinary excretion (β = 0.54, p < 0.01). Accelerated postnatal growth was positively related with kidney volume (β = 0.35, p < 0.05).

CONCLUSIONS

Among our patient cohort, renal function was well preserved at ages 4-15.5 years in children who were born with a SK. However, both their higher blood pressure and RI and the correlation of 24-h albumin urinary excretion with length of follow-up time underline the need for monitoring to detect early signs of glomerular hyperfiltration and, if necessary, implement timely intervention. SK hypertrophy was found to be correlated with postnatal growth.

Evaluation of renal function after successful treatment for unilateral, non-syndromic Wilms tumor

Impaired renal function may occur in experimental animals following surgical removal of most functioning renal tissue ("hyperfiltration injury"). Although end-stage renal disease is uncommon among long-term survivors of unilateral, non-syndromic Wilms tumor, concern has been expressed that there may be an increased risk of less serious, but progressive, renal function impairment among these individuals. The recent development of equations for estimating glomerular filtration rate (eGFR) has facilitated the study of renal function in Wilms tumor survivors. However, the estimating equations were developed to categorize individuals with chronic kidney disease and have significant limitations with regard to the accuracy of individual GFR estimates. These limitations must be considered when utilizing the estimating equations in cross-sectional or longitudinal evaluations of renal function in cohorts of patients who have been treated successfully for Wilms tumor or other childhood cancers.

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

BACKGROUND

Great improvements in diagnostics and treatment for malignant disease in childhood have led to a major increase in survival. However, childhood cancer survivors (CCS) are at great risk for developing adverse effects caused by multimodal treatment for their malignancy. Nephrotoxicity is one of these known (acute) side effects of several treatments, including cisplatin, carboplatin, ifosfamide, radiotherapy and nephrectomy, and can cause glomerular filtration rate impairment, proteinuria, tubulopathy and hypertension. However, evidence about the long-term effects of these treatments on renal function remains inconclusive. To reduce the number of (long-term) nephrotoxic events in CCS, it is important to know the risk of, and risk factors for, early and late renal adverse effects, so that ultimately treatment and screening protocols can be adjusted.

OBJECTIVES

To evaluate existing evidence on the effects of potentially nephrotoxic treatment modalities on the prevalence of and associated risk factors for 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 healthy controls or CCS treated without potentially nephrotoxic treatment.

SEARCH METHODS

We searched the following electronic databases: the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 4, 2011), MEDLINE/PubMed (from 1945 to December 2011) and EMBASE/Ovid (from 1980 to December 2011).

SELECTION CRITERIA

With the exception of 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 children and adults who were treated for a paediatric malignancy (aged 18 years or younger at diagnosis) with cisplatin, carboplatin, ifosfamide, radiation including the kidney region and/or a nephrectomy.

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

The search strategy identified 5504 studies, of which 5138 were excluded on the basis of title and/or abstract. The full-text screening of the remaining 366 articles resulted in the inclusion of 57 studies investigating the prevalence of and sometimes also risk factors for early and late renal adverse effects of treatment for childhood cancer. The 57 studies included at least 13,338 participants of interest for this study, of whom at least 6516 underwent renal function testing. The prevalence of renal adverse effects ranged from 0% to 84%. This variation may be due to diversity in included malignancies, prescribed treatments, reported outcome measurements and the methodological quality of available evidence.Chronic kidney disease/renal insufficiency (as defined by the authors of the original studies) was reported in 10 of 57 studies. The prevalence of chronic kidney disease ranged between 0.5% and 70.4% in the 10 studies and between 0.5% and 18.8% in the six studies that specifically investigated Wilms' tumour survivors treated with a unilateral nephrectomy.A decreased (estimated) glomerular filtration rate was present in 0% to 50% of all assessed survivors (32/57 studies). Total body irradiation; concomitant treatment with aminoglycosides, vancomycin, amphotericin B or cyclosporin A; older age at treatment and longer interval from therapy to follow-up were significant risk factors reported in multivariate analyses. Proteinuria was present in 0% to 84% of all survivors (17/57 studies). No study performed multivariate analysis to assess risk factors for proteinuria.Hypophosphataemia was assessed in seven studies. Reported prevalences ranged between 0% and 47.6%, but four of seven studies found a prevalence of 0%. No studies assessed risk factors for hypophosphataemia using multivariate analysis. The prevalence of impairment of tubular phosphate reabsorption was mostly higher (range 0% to 62.5%; 11/57 studies). Higher cumulative ifosfamide dose, concomitant cisplatin treatment, nephrectomy and longer follow-up duration were significant risk factors for impaired tubular phosphate reabsorption in multivariate analyses.Treatment with cisplatin and carboplatin was associated with a significantly lower serum magnesium level in multivariate analysis, and the prevalence of hypomagnesaemia ranged between 0% and 37.5% in the eight studies investigating serum magnesium.Hypertension was investigated in 24 of the 57 studies. Reported prevalences ranged from 0% to 18.2%. A higher body mass index was the only significant risk factor noted in more than one multivariate analysis. Other reported factors that significantly increased the risk of hypertension were use of total body irradiation, abdominal irradiation, acute kidney injury, unrelated or autologous stem cell donor type, growth hormone therapy and older age at screening. Previous infection with hepatitis C significantly decreased the risk of hypertension.Because of the profound heterogeneity of the studies, it was not possible to perform any meta-analysis.

AUTHORS' CONCLUSIONS

The prevalence of renal adverse events after treatment with cisplatin, carboplatin, ifosfamide, radiation therapy involving the kidney region and/or nephrectomy ranged from 0% to 84%. With currently available evidence, it was not possible to draw any conclusions with regard to prevalence of and risk factors for renal adverse effects. Future studies should focus on adequate study design and reporting and should deploy multivariate risk factor analysis to correct for possible confounding. Until more evidence becomes available, CCS should be enrolled into long-term follow-up programmes to monitor their renal function and blood pressure.

The late effects of anticancer therapy after childhood Wilm's tumor: the role of diastolic function and ambulatory blood pressure monitoring

OBJECTIVE

Wilms' tumor, or nephroblastoma, is the most common primary malignant renal tumor of childhood. The excellent outcome now expected for most children with this tumor is attributed to the combination of effective adjuvant chemotherapy, improved surgical and anesthetic techniques and also the radiosensitivity of the tumor. The numerous organ systems are subject to the late effects of anticancer therapy. The aim of this study was to investigate the blood pressure profile and ambulatory blood pressure monitoring, and also cardiac diastolic functions and pulmonary venous flow in 25 children with unilateral Wilms' tumor in remission.

METHODS

The patient group consists of 25 patients who successfully completed anticancer treatment for unilateral Wilms' tumor. Thirty-three age-, weight- and height-matched healthy children were considered as a control group for an echocardiographic study. Also, 20 age-, weight- and height-matched healthy children were considered as a control group for the ambulatory blood pressure monitoring study.

RESULTS

In our study, 24 h, daytime and night-time systolic blood pressure and night-time diastolic blood pressure measurements were found to be significantly increased in the patient group compared with healthy children. We detected diastolic filling pattern abnormalities. We also found increase in pulmonary venous flow (systolic and diastolic) in Wilms' tumor group.

CONCLUSIONS

We suggest the regular follow-up of survivors of Wilms' tumor for care and prevention of cardiovascular diseases.

Pregnancy outcome after treatment for Wilms tumor: a report from the national Wilms tumor long-term follow-up study

PURPOSE

This study was undertaken to evaluate the effect of prior treatment with radiation therapy or chemotherapy for unilateral Wilms tumor (WT) diagnosed during childhood on pregnancy complications, birth weight, and the frequency of congenital malformations in live-born offspring.

PATIENTS AND METHODS

We reviewed pregnancy outcomes among female survivors and partners of male survivors of WT treated on National Wilms Tumor Studies 1, 2, 3, and 4 by using a maternal questionnaire and a review of both maternal and offspring medical records.

RESULTS

We received reports of 1,021 pregnancies with duration of 20 weeks or longer, including 955 live-born singletons, for whom 700 sets of maternal and offspring medical records were reviewed. Rates of hypertension complicating pregnancy (International Classification of Diseases [ICD] code 642), early or threatened labor (ICD-644) and malposition of the fetus (ICD-652) increased with increasing radiation dose in female patients. The percentages of offspring weighing less than 2,500 g at birth and of those having less than 37 weeks of gestation also increased with dose. There was no significant trend with radiation dose in the number of congenital anomalies recorded in offspring of female patients.

CONCLUSION

Women who receive flank radiation therapy as part of the treatment for unilateral WT are at increased risk of hypertension complicating pregnancy, fetal malposition, and premature labor. The offspring of these women are at risk for low birth weight and premature (ie, < 37 weeks gestation) birth. These risks must be considered in the obstetrical management of female survivors of WT.

The role of nitric oxide and ferritin in the pathogenesis of alcoholic liver disease: a controlled clinical study

The role of ferritin in fibrogenesis of liver parenchyma in patients with alcoholic liver disease has been investigated in previous studies. Ferritin was shown to be an indirect marker of ferum deposition in liver parenchyma in alcohol liver disease. The aim of the present study was to examine the role of nitric oxide (NO) in the pathogenesis of alcoholic liver disease as well as the influence of NO on iron (ferritin) metabolism in patients with alcoholic liver disease. Serum concentrations of NO and iron markers (iron, total iron binding capacity, ferritin) were measured in 30 male patients (aged 20-60 years) with alcoholic liver disease, as well as from a control group (30 male patients (aged 20-60 years) without liver disease). NO concentration was detected by measuring production of nitrates and nitrites using classical colorimetric Griess reactions. There was a statistically significant increase in serum NO concentration in patients with alcoholic liver disease compared to the control group (mean +/- SEM; 41,2 +/- 25,3 vs. 28,9 +/- 12,3 mmol/dm3, respectively; p<0,03). Similarly, serum iron levels (18,7 +/- 8,2 vs. 13,2 +/- 10,2 g/100 cm3, respectively; p<0,03) and serum total iron binding capacity (51,3 +/- 13,9 vs. 41,4 +/- 11,4 micromol/dm3, respectively; p<0,005) were also significantly higher in patients with alcoholic liver disease compared to control patients. The serum concentration of ferritin was 27% higher in patients with alcoholic liver disease than in the control group; however this was not statistically significant (283,2 +/- 291,0 vs. 222,9 +/- 252,0 g, respectively; p<0,4). There was no correlation between NO and ferritin in the investigated groups. These results suggest a possible role of NO and iron in the pathogenesis of alcoholic liver disease. NO and iron may be used as non-invasive predictors of liver damage. Also the role of iron in sera, and its deposition in liver parenchyma, could be used in clinical practice, especially in regards to assessing the fibrogenesis of liver parenchyma induced by ferritin.

Renal agenesis and unilateral nephrectomy: what are the risks of living with a single kidney?

The long-term outlook for patients with unilateral renal agenesis or following unilateral nephrectomy in childhood is controversial. Animal studies suggest that the resultant compensatory increase in glomerular filtration might lead to progressive damage to the remaining renal tissue and may generate hypertension. Human studies addressing these concerns are limited in number and are difficult to interpret because they are small, retrospective, or cross sectional with significant variations in duration and completeness of follow-up. The published studies suggest that renal function remains stable for several decades in the majority of subjects. The clinical significance of mild-grade proteinuria and hypertension seen in some patients is unknown. Longitudinal studies are needed to understand the long-term effect and significance of the several pathophysiological changes observed in the solitary kidney.

Renal late effects in patients treated for cancer in childhood: a report from the Children's Oncology Group

Improvements in childhood cancer therapy have led to increasing numbers of long-term survivors. These survivors are at risk for a variety of late effects due to the disease itself, treatment exposures (surgery, chemotherapy, and radiotherapy), underlying medical problems, and health behaviors. The COG LTFU Guidelines are risk-based, exposure-related recommendations for the identification and management of late effects due to therapies utilized in the treatment of childhood cancer, and are designed for asymptomatic survivors presenting for routine medical follow-up 2 or more years after completion of cancer therapy. The COG Guidelines Task Force on Urinary Tract Complications conducted an extensive review of the medical literature via MEDLINE. Specific treatment exposures which were reviewed include nephrectomy, chemotherapy regimens known to be nephrotoxic (cisplatin, carboplatin, ifosfamide, and methotrexate), and renal irradiation. Literature sources were ranked according to the strength of evidence and are cited in the review. This review summarizes the literature that supported the recommendations for cancer survivors at risk for nephrotoxicity previously outlined in the Children's Oncology Group Long-Term Follow-Up Guidelines for Survivors of Childhood, Adolescent and Young Adult Cancers (COG LTFU Guidelines).

Renal function after ifosfamide, carboplatin and etoposide (ICE) chemotherapy, nephrectomy and radiotherapy in children with Wilms tumour

We prospectively evaluated tumour response and renal function in 12 newly diagnosed children with high-risk Wilms tumour receiving ifosfamide, carboplatin and etoposide (ICE) chemotherapy. Two cycles of ICE were followed by 5 weeks of vincristine, dactinomycin and doxorubicin (Adriamycin) (VDA), and nephrectomy, radiotherapy, additional VDA, and a third ICE cycle. Carboplatin dosage was based on glomerular filtration rate (GFR) to achieve targeted systemic exposure (6mg/ml min). Mean GFR (measured by technetium 99m-DTPA clearance) declined by 7% after 2 cycles of ICE and by 38% after nephrectomy; the mean carboplatin dose was reduced 32% after nephrectomy. Mean GFR remained stable after the third ICE cycle. Although urinary beta(2)-microglobulin excretion increased during therapy, no patient had clinically significant renal tubular dysfunction at the end of treatment. Treatment with ICE, nephrectomy and radiotherapy significantly reduces GFR, largely as the result of nephrectomy. Adjustment of carboplatin dosage on the basis of GFR and careful monitoring of renal function may alleviate nephrotoxicity.

Consequences of Intrauterine Growth Restriction for the Kidney

Low birth weight due to intrauterine growth restriction is associated with various diseases in adulthood, such as hypertension, cardiovascular disease, insulin resistance and end-stage renal disease. The purpose of this review is to describe the effects of intrauterine growth restriction on the kidney. Nephrogenesis requires a fine balance of many factors that can be disturbed by intrauterine growth restriction, leading to a low nephron endowment. The compensatory hyperfiltration in the remaining nephrons results in glomerular and systemic hypertension. Hyperfiltration is attributed to several factors, including the renin-angiotensin system (RAS), insulin-like growth factor (IGF-I) and nitric oxide. Data from human and animal studies are presented, and suggest a faltering IGF-I and an inhibited RAS in intrauterine growth restriction. Hyperfiltration makes the kidney more vulnerable during additional kidney disease, and is associated with glomerular damage and kidney failure in the long run. Animal studies have provided a possible therapy with blockage of the RAS at an early stage in order to prevent the compensatory glomerular hyperfiltration, but this is far from being applicable to humans. Research is needed to further unravel the effect of intrauterine growth restriction on the kidney.

At what level of unilateral renal impairment does contralateral functional compensation occur?

Functional compensation occurs in a kidney when the function of the contralateral kidney is decreased or absent. What is, however, not documented is the level of unilateral renal impairment at which functional compensation occurs. Split function, as obtained from a radionuclide renogram, can only show the asymmetry between both kidneys. The aim of the present work was to evaluate at what level of unilateral impairment a functional compensation can be observed in the contralateral normal kidney. From a large database, 180 children over 2 years of age with unilateral pathology were retrospectively selected. All of them underwent a radionuclide study, combining a technetium-99m mercaptoacetyltriglycine (Tc-99m MAG3) renogram associated with a chromium-51 ethylenediaminetetraacetic acid (Cr-51 EDTA) overall clearance, allowing a precise estimation of single-kidney glomerular filtration rate (SKGFR). Below 30-35 ml/min/1.73 m2, there was a significant inverse correlation between SKGFR on the normal and the abnormal side. Above this level, no such correlation was observed, the mean SKGFR on the normal side remaining around 58 ml/min/1.73 m2, whatever the value of SKGFR on the abnormal side. In pediatric patients, hyperfunction occurs when SKGFR of the diseased kidney is below 30-35 ml/min/1.73 m2.

Nephrotoxicity in survivors of Wilms' tumours in the North of England

One aspect of concern for survivors of Wilms' tumour has been the late outcome in terms of renal function. Previous studies have documented low glomerular filtration rate and high blood pressure in some patients. Furthermore, disorders in tubular function (especially urinary concentration defects) have been suggested but not confirmed in small studies. The aim of this study was to determine the prevalence and nature of subclinical and overt glomerular, proximal and distal renal tubular toxicity in a population based cohort of survivors of Wilms' tumour. Forty patients (24 female) with a median age of 4.3 years (3 months-11.8 years) at diagnosis were studied. Median follow-up was 8.8 (range 0.06-27.5) years. Glomerular filtration rate was measured by (51)Cr-EDTA plasma clearance, proximal tubular function by electrolyte fractional excretions, urine excretion of low molecular weight proteins (retinol-binding protein) and renal tubular enzymes (alanine aminopeptidase; N-acetylglucosaminidase) and distal tubular function by the osmolality of the first two urines of the day on 3 consecutive days. Renal size (ultrasound) and blood pressure were also measured. Mean (range) glomerular filtration rate was 100 (61-150) ml min(-1) 1.73 m(-2). Nine were below the reference range for healthy individuals with two kidneys. Most serum electrolyte concentrations (sodium, potassium, chloride, calcium, magnesium and phosphate) fell within the normal range for age, as did the fractional excretions. The values that fell outside the normal range were only marginally abnormal. Subclinical measures of tubular toxicity (retinal-binding protein, alanine aminopeptidase, N-acetylglucosaminidase) were abnormal in only four patients. Thirty-seven patients achieved maximal urine osmolalities > or =800 mOsm kg(-1), but three failed to achieve this value even after DDAVP administration. Two patients had evidence of increased urinary albumin excretion. Compensatory renal hypertrophy was seen in all but two patients, but blood pressure was within normal limits in all patients. Current and past treatment for Wilms' tumour does not have any clinically important nephrotoxic effect in the majority of patients. This finding will enable paediatric oncologists to reassure patients and parents that treatment for Wilms' tumour rarely causes long-term renal impairment.

Long-term renal function in patients with irradiated bilateral Wilms tumor. National Wilms' Tumor Study Group

The treatment of bilateral Wilms tumor (BWT) involves a multidisciplinary approach including surgery, chemotherapy, and radiation therapy. The long-term renal function in patients receiving all three treatment modalities has not been evaluated. Long-term renal function was evaluated in 81 children with synchronous BWT who received radiation therapy as part of their treatment. Renal function was assessed by measuring blood urea nitrogen (BUN) and serum creatinine (Cr). The normal range for the BUN was defined as 10-24 mg/dl, and the Cr was considered normal at levels of <1.5 mg/dl. Moderate elevations were defined as a BUN of 25-50 mg/dl and/or a Cr of 1.6-2.5 mg/dl and marked elevations as a BUN of >50 mg/dl and/or a Cr of >2.5 mg/dl. BUN and Cr levels were measured prior to treatment and at the following intervals: 6 months after treatment, 1 year after treatment, 2 years after treatment, and at last follow-up. Any elevation during the posttreatment follow-up period was considered abnormal. A total of 28 children (34.6%) had elevated BUN and/or Cr levels, and 18 had moderate and 10 had marked renal insufficiency. No dose-response relationship was established when comparing the radiation doses of those with elevated values to those with normal values. The renal complication rate was moderate, and other factors including surgery, extent and nature of chemotherapy, and recurrent tumor must also be taken into account. The elevations present in several children could be attributed to tumor recurrence and in one case to gentamicin toxicity. The management of children with BWT should consider all of these risks, and attempts to preserve renal parenchyma are warranted.

The effect of Wilms tumor chemotherapy on contralateral renal growth after nephrectomy

PURPOSE

Our aim was to evaluate the effect of current Wilms tumor chemotherapy on renal growth and function after unilateral nephrectomy.

MATERIALS AND METHODS

Yorkshire piglets were enrolled in 2 study groups: group 1--6 underwent unilateral nephrectomy and placebo infusion, and group 2--10 underwent nephrectomy, and infusion of 7.5 mcg/kg. actinomycin D and 0.75 mcg/m2 vincristine according to the National Wilms Tumor Study 4 protocol. Weekly measurements of renal size by ultrasound and gross specimens at sacrifice at age 11 weeks were examined and weekly laboratory studies were recorded. Growth rates of renal length and volume were evaluated by linear regression analysis. Terminal renal length and volume were compared between groups.

RESULTS

Mean slope plus or minus standard deviation of the rate of growth in length in the control and chemotherapy groups was 0.067 +/- 0.004 and 0.074 +/- 0.011, respectively (p < or = 0.148, not statistically significant). Mean slope of growth in volume was 1.401 +/- 0.240 versus 1.642 +/- 0.456 (p < or = 0.252), average terminal renal length was 10.71 +/- 1.02 versus 11.58 +/- 1.03 cm (p < or = 0.13, not significant) and mean final volume was 128.67 +/- 32.41 versus 137 +/- 32.52 cc (p < or = 0.65). No differences in final serum creatinine levels were noted.

CONCLUSIONS

Chemotherapy for Wilms tumor did not adversely affect contralateral renal growth or function in a nephrectomized piglet model.

Long-term renal function in the posterior urethral valves, unilateral reflux and renal dysplasia syndrome

PURPOSE

The syndrome of posterior urethral valves, persistent unilateral reflux and renal dysplasia (VURD) is said to be protective of the contralateral nonrefluxing kidney and the outcome for renal function is reported to be excellent. We tested this hypothesis in our patients by replicating previous studies but with longer followup and glomerular filtration rate data.

MATERIALS AND METHODS

We retrospectively reviewed the records of 183 boys presenting with posterior urethral valves between 1980 and 1989, including 12 who underwent nephrectomy for ipsilateral nonfunction and fulfilled all criteria for the VURD syndrome. Mean age at the most recent followup was 8.5 years. Serial serum creatinine levels and glomerular filtration rates were analyzed and compared to age matched normal values.

RESULTS

Histological evaluation revealed dysplasia in all kidneys, confirming the VURD syndrome. Followup plasma creatinine was normal 67% of the patients during year 2 of life, 50% between ages 4 and 5 years, and only 30% between ages 8 and 10 years. Glomerular filtration rate was within the normal range in 25% of boys tested in year 2 of life, and between ages 5 and 8 years.

CONCLUSIONS

Our data do not support the protective effect of the VURD syndrome on long-term renal function. All patients with posterior urethral valves require diligent long-term followup.

[Renal function after nephrectomy for Wilms' tumor]

BACKGROUND

Most children with Wilms tumour recover after nephrectomy, chemotherapy and sometimes radiotherapy. It is therefore important to assess their long-term renal function.

POPULATION AND METHODS

Thirty-three patients with Wilms tumour experienced unilateral nephrectomy between 1986 and 1993: three were excluded; 23 were staged as grade I, one at grade II, two at grade III and four at grade IV. They were treated with SIOP 6 and SIOP 9 protocols. The results were compared to five controls who underwent unilateral nephrectomy including three for renal trauma. The glomerular filtration rate (GFR) was measured by inulin clearance and the renal plasma flow (RPF) by para-amino-hippuric acid clearance.

RESULTS

The mean age at nephrectomy was 3.4 +/- 2.5 years (median: 3, range: 0.2-10.6) and the duration of follow-up was 4.6 +/- 3.1 years (median: 4.5, range: 1-8.5), the GFR was 93 +/- 13 mL/min/1.73 m2 (median: 93, range: 73-130), the RPF was 441 +/- 85 mL/min/1.73 m2 (median: 453, range: 236-650) and the filtrated fraction (FF) was 0.21 +/- 0.03 (median: 0.20, range: 0.18-0.31). The difference in renal function between patients and controls was not significant (GRF: 86 +/- 12 mL/min/1.73 m2, RPF: 486 +/- 185 mL/min/1.73 m2, FF: 0.22 +/- 0.03). The electrolyte reabsorption rate was normal and none of the patients suffered from arterial hypertension. Fourteen children had urinary albumin: creatinine ratio > 2 g/mol. When comparing patients according to the duration of follow-up after nephrectomy (< 4 years vs > 4 years), the renal function was not statistically different. The age at nephrectomy (< 2 years vs > 2 years) did not increase the risk of renal impairment.

CONCLUSION

Children with Wilms tumour who were treated with nephrectomy and non-nephrotoxic drugs (actinomycin, vincristine, epiadriamycin) have a good long-term renal outcome. It is speculated that systematic renal investigation should be limited to those children with increased microalbuminuria and/or elevated blood pressure.

Compensatory hypertrophy and progressive renal damage in children nephrectomized for Wilms' Tumor

Clinical, biochemical, and sonographic evaluation of the remaining kidney function and size was performed in 34 patients, 12 males and 22 females, ages 2.1-19.6 years, nephrectomized (NP) for Wilms' tumor (WT) at least 2 years before (mean 8.6). All patients had normal blood pressure and serum bicarbonates. Two of them had microhematuria, four proteinuria 4 mg/m2/hr, and 11 microalbuminuria (MA) > 20 mg/24 hr. Only one patient had reduced creatinine clearance and maximum bipolar length (MBL) as well as kidney volume (KV) < 100% of expected. In the other patients, average MBL was 128 +/- 11% (P = 0.0001). MBL, but not KV, was inversely correlated (P = 0.04) to age at NP. KV, but not MBL, was directly correlated (P = 0.009) to MA. Average MA was 48 +/- 94 mg/24 hr and was correlated to the time from NP (P = 0.026). The remaining kidney increases in volume much more than in length. The increase in KV is related to the degree of MA, whereas the increase in MBL is higher in subjects younger at NP. The high prevalence of significant MA, which is in turn related to the time from NP and to the KV, raises some concerns about the long-term renal prognosis of children NP for WT.

Renal function after unilateral nephrectomy for Wilms' tumour: the influence of radiation therapy

The effect of therapy on renal function after unilateral nephrectomy for Wilms' tumour was studied. In the second year following unilateral nephrectomy, glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) were estimated simultaneously by measuring 125I-iothalamate clearance and 131I-hippurate clearance. Of 41 evaluable patients, 29 received chemotherapy as sole treatment modality following nephrectomy (group 1); 12 patients additionally received radiation therapy to a field that included the remaining kidney (group 2). Results were expressed as standard deviation scores (z-scores). In group 1, mean z-score for GFR was -0.27 (94.6% of normal) and in group 2 mean z-score was -1.51 (72.7% of normal for two kidneys) (P = 0.022, Mann-Whitney U-test). Mean z-score for ERPF was -0.09 (97.0%) in group 1 and -1.53 (73.8%) in group 2 (P = 0.039). It was concluded that the combination of chemotherapy and radiation therapy, in contrast to chemotherapy alone, negatively affects the ability of the remaining kidney to adjust its function after the loss of its counterpart.

Growth of the solitary kidney after nephrectomy in children with unilateral Wilms' tumor

OBJECTIVE

We reviewed the length of the solitary kidney from all ultrasound examinations in 34 children who had undergone unilateral nephrectomy for Wilms' tumor, in order to determine the frequency of renal hypertrophy in this population. Standard sonographic criteria for nephromegaly were used.

MATERIALS AND METHODS

We generated a z-score for each measurement of the renal length, using an interpolated computer model based on published standards for sonographic renal length in relation to age. A retrospective age- and gender-matched control population of children with sonographically normal paired kidneys was generated from a departmental computerized pediatric uroradiology data base, and their ipsilateral renal lengths were compared with those of the study patients. Sonographic renal hypertrophy (SRH) was defined by two or more consecutive measurements of the renal length exceeding two standard deviations longer than the mean for the patient's age, with no later normal measurement.

RESULTS

Seventeen (50 %) of the 34 patients developed SRH. The latest measurements of the solitary kidney in the patients were significantly longer (mean z = 2.210) than in their controls (mean z = 0.040), even among the patients who did not develop SRH (patients' mean z = 1.000, controls' mean z = -0. 210, p < 0.001). Because boys had slightly longer kidneys than girls (both patients and controls), SRH was also noted more often in boys. The frequency of SRH was unrelated to age at nephrectomy, side of the solitary kidney, tumor stage, chemotherapy regimen, or treatment with radiation therapy.

CONCLUSIONS

Although renal growth in a solitary kidney is accelerated in most children after unilateral nephrectomy for Wilms' tumor, the sonographic length of the solitary kidney will be larger than normal in only half of the patients.

Renal function following unilateral nephrectomy for neuroblastoma and Wilms' tumour

To estimate the side effects of chemotherapy and the influence of age at the time of nephrectomy on renal function, we investigated renal function in 34 uninephrectomised children with neuroblastoma (NB) or Wilms' tumour (WT). The results were compared with 6 controls who underwent nephrectomy for non-malignant disease. Study of renal function was primarily based on the clearance of inulin and para-aminohippuric acid (Cin and CPAH, ml/min per 1.73 m2). No significant differences in Cin/CPAH (mean +/- SD) were found between the NB group (90 +/- 24/421 +/- 95), WT group (85 +/- 17/386 +/- 104) and the controls (93 +/- 13/430 +/- 61). Children with NB and WT were divided into two subgroups according to the theoretical nephrotoxic risk. There was no significant difference in renal function between NB or between WT subgroups. Cumulative cisplatin doses in children with NB did not affect renal function significantly. The age at time of unilateral nephrectomy (< or = 2 years vs. > 2 years) was not associated with a higher risk of renal damage in WT children, whereas in NB children the filtration fraction (Cin:CPAH) was higher in younger children (mean +/- SD: 0.243 +/- 0.023 vs. 0.191 +/- 0.041). In conclusion, uninephrectomised children with NB are supposed to have a higher risk of drug-induced renal impairment compared with those with WT. Our data do not confirm this hypothesis, since renal function was comparable to controls in both groups, except in younger patients with NB who show a high filtration fraction. Since the survival of children with NB has improved, a longer follow-up of their renal function in needed.

Renal size and function after cure of Wilms' tumour

Now that most patients with Wilms' tumour are cured, it is practicable to study the long-term morbidity of their treatment and use this information to reduce treatment sequelae in the future. In this study we evaluate the size and function of the remaining kidney in 53 survivors of Wilms' tumour with a mean off treatment follow-up of 13 years. There was evidence of renal dysfunction in 17 (32%), including ten (19%) with a low GFR (< 80 ml/min/1.73 m2SA), six (11%) with hypertension and five (9%) with increased urinary albumin excretion. Measurements of renal size showed 'good' renal compensatory hypertrophy in only 55% of patients. 'Good' refers to renal size of more than 2 s.d. above the mean renal length for children with two kidneys. There were no correlations between GFR, renal size, blood pressure, microalbuminuria or type of treatment. However, children less than 24 months at diagnosis and children receiving chemotherapy with radiation doses to remaining kidney of more than 1200 cGy had a worse renal prognosis. Patients whose Wilms' tumour is diagnosed in infancy should have careful long-term follow-up of renal function and size. Older patients may safely be followed up less often, unless their remaining kidney was received > 1200 cGy.

Renal functional reserve in long-term survivors of unilateral Wilms tumor

We hypothesized that long-term survivors of unilateral Wilms tumor would have a decreased renal functional reserve secondary to the consequences of hyperfiltration in the nephrons of the remaining kidney. Therefore we evaluated the renal functional reserve in 12 long-term survivors of Wilms tumor after unilateral nephrectomy (mean +/- SE: 15 +/- 1.1 years; range 9 to 23 years). We measured the creatinine clearance before and after an acute, oral protein load to determine the renal functional reserve. Study subjects and control subjects were matched for age, gender, and body surface area. The basal creatinine clearances were similar (Wilms group 132 +/- 13 vs control group 142 +/- 11 ml/min/1.73 m2; p = not significant (NS]. There was no significant difference in the renal functional reserve between long-term survivors of Wilms tumor and matched control subjects (Wilms group 17 +/- 11 vs control group 25 +/- 11 ml/min/1.73 m2; p = NS). The change in creatinine clearance was not secondary to volume expansion because the fractional excretion of sodium was unchanged with protein loading (Wilms group before loading 0.92 +/- 0.12 vs after loading 0.99 +/- 0.13 (p = NS); control group before loading 0.91 +/- 0.12 vs after loading 1.0 +/- 0.14 (p = NS)). We conclude that up to 15 years after nephrectomy for unilateral Wilms tumor in childhood, there is no evidence of hyperfiltration injury.

Renal growth and function 11-28 years after treatment of Wilms' tumour

In order to obtain more information on the long-term effects of treatment of Wilms' tumour we investigated 30 subjects treated at the Children's Hospital between 1960 and 1976. All had been nephrectomized and in 4 the length of the remaining kidney was subnormal. In the other subjects kidney length was related to follow up time and age at follow up. Blood pressure was elevated in 5 subjects. Urinary albumin excretion deviated only slightly from normal. Tubular functions were well preserved in all subjects. In this small series we were unable to establish any relation between the abnormalities observed and the treatment given. Our results suggest that, despite wide interindividual variation those who survive Wilms' tumours seldom have long-term renal complications.

Long-term follow-up after unilateral nephrectomy and radiotherapy for Wilms' tumour

Twenty-nine patients who had had unilateral nephrectomy for Wilms' tumour in one hospital were known to have survived more than 12 years. Sixteen agreed to attend for clinical review, of whom 14 had estimation of serum creatinine, 24-h urine protein excretion and endogenous creatinine clearance. The follow-up period was 13-26 years (median 17 years). All but one had had radiotherapy and all had chemotherapy (actinomycin D, 16; vincristine, 5). Some degree of kyphoscoliosis was present in all except the patient who did not receive radiotherapy. Four patients had diastolic blood pressure 90 mmHg or greater. Two patients had mild proteinuria (392, 361 mg/day). Serum creatinine ranged from 53 to 125 mumol/l and endogenous creatinine clearance ranged from 39 to 173 ml/min (median 81, mean 89). Of the 7 patients who were 20-26 years post-nephrectomy, 2 were hypertensive and 1 had elevated urinary protein excretion. We conclude that the long-term prognosis of unilateral nephrectomy in childhood is good.

No microalbuminuria or other adverse effects of long-standing hyperfiltration in humans with one kidney

Hypertrophy and hyperfiltration are characteristic features of single kidneys and kidneys of patients with insulin-dependent diabetes mellitus (IDDM). In both cases the hyperfiltration has been suggested to be involved in the pathogenesis of renal functional deterioration. We studied the effect of long-standing hyperfiltration on kidney function in 29 subjects with one kidney, three of whom were insulin-dependent diabetics. Four groups were studied: (1) uninephrectomized less than 10 years since uninephrectomy (UN) (n = 7; age, 30 +/- 6 years); (2) uninephrectomized greater than or equal to 10 years since UN (19 +/- 11 years, 10 to 52); n = 14; age, 38 +/- 15 years; (3) congenital unilateral renal agenesis (n = 5, age, 39 +/- 16 years); and (4) IDDM patients with one kidney (n = 3; age, 28 to 52 years; diabetes duration, 8 to 31 years; years with one kidney, 18 to 30). Glomerular filtration rate (GFR) and renal plasma flow (RPF) were measured by the constant infusion technique, kidney volume (KV) by ultrasonic scanning, and urinary albumin excretion rate (UAE) by radioimmunoassay. In all subjects GFR, RPF, and KV were within the normal range, representing a single kidney hyperfiltration of approximately 70% and hypertrophy of approximately 100%. Only one of the subjects with renal agenesis had an elevated UAE (117 micrograms/min); the remainder had a normal UAE, ie, less than 10 micrograms/min, and the diabetics were below the risk level of 20 micrograms/min. Serum creatinine was normal and BP was slightly elevated in only three subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Kidney function in adults born with unilateral renal agenesis or nephrectomized in childhood

We have evaluated the long-term prognosis in an unselected group of adult patients either uni-nephrectomized in childhood because of hydronephrosis or born with unilateral renal agenesis. Thirty-six patients aged 7-47 years were followed for 7-40 years. In 23 control subjects aged 20-47 years the glomerular filtration rate (GFR) and the p-aminohippuric acid clearance (CPAH) did not change significantly with age. In patients with a single kidney the size of that kidney was larger and GFR and CPAH were higher than single kidney values in control subjects. However, in patients with a single kidney since childhood the GFR and the CPAH declined slowly but significantly during the follow-up period. Significant microalbuminuria occurred in 47% of the patients with a single kidney and was more frequent with a longer follow-up period. No patient had renal insufficiency or a marked increase in arterial blood pressure. We conclude that in patients with a single kidney since childhood the long-term prognosis is good, but the late decrease in GFR and increase in albumin excretion may indicate a moderate risk for premature renal damage.