Case records of the Massachusetts General Hospital. Weekly clinicopathological exercises. Case 17-1985. A 13-year-old boy with aniridia and proteinuria 11 years after nephrectomy for a Wilms' tumor

Immune-complex glomerulonephritis with a membranoproliferative pattern in Frasier syndrome: a case report and review of the literature

Background

Mutations in the Wilms tumor 1 gene cause a spectrum of podocytopathy ranging from diffuse mesangial sclerosis to focal segmental glomerulosclerosis. In a considerable fraction of patients with Wilms tumor 1 mutations, the distinctive histology of immune-complex-type glomerulonephritis has been reported. However, the clinical relevance and etiologic mechanisms remain unknown.

Case presentation

A 5-year-old child presented with steroid-resistant nephrotic range proteinuria. Initial renal biopsy revealed predominant diffuse mesangial proliferation with a double-contour and coexisting milder changes of focal segmental glomerulosclerosis. Immunofluorescence and electron microscopy revealed a full-house-pattern deposition of immune complexes in the subendothelial and paramesangial areas. Serial biopsies at 6 and 8 years of age revealed that more remarkable changes of focal segmental glomerulosclerosis had developed on top of the initial proliferative glomerulonephritis. Identification of a de novo Wilms tumor 1 splice donor-site mutation in intron 9 (NM_024426.6:c.1447 + 4C > T) and 46,XY-gonadal dysgenesis led to the diagnosis of Frasier syndrome.

Conclusions

Our findings, together with those of others, point to the importance of heterogeneity in clinicopathological phenotypes caused by Wilms tumor 1 mutations and suggest that immune-complex-mediated membranoproliferative glomerulopathy should be considered as a histological variant.

Membranoproliferative glomerulonephritis associated with a mutation in Wilms' tumour suppressor gene 1

Wilms' tumour suppressor gene 1 (WT1) encodes a transcription factor required for normal development of the genitourinary system. In the kidney, mutations in WT1 can cause diffuse mesangial sclerosis or focal segmental glomerulosclerosis. Here, we report on a girl with a mutation in WT1, who developed membranoproliferative glomerulonephritis (MPGN) 3 years after completion of treatment for Wilms' tumour. This finding extends the spectrum of glomerular disease seen with WT1 mutations and could have implications for the screening of children with MPGN.

Hypertension and prehypertension in long-term survivors of childhood and adolescent cancer

BACKGROUND

Hypertension as a late effect following childhood and adolescent cancer has received little attention. Since obesity, a known risk factor for hypertension, is increased following some childhood cancers, it seems likely that significant numbers of survivors would have hypertension.

PROCEDURES

The records of patients seen in the Long Term Follow Up Clinic of Children's National Medical Center were examined for a single institution, retrospective study of blood pressure in survivors of childhood and adolescent cancer. Of 103 consecutive survivors who attended the clinic from January 1 through June 30, 2004, 51 (49.5%) were female and 52 (50.5%) were male. Their mean age was 14.6 years. Systolic and diastolic blood pressures for children and adolescents under 18 years of age were evaluated for hypertension and prehypertensive according to standards for age, sex, and height. Blood pressures for adults 18 years of age and older were evaluated according to standard adult values. Children and adolescents were evaluated for obesity and overweight according to body mass index (BMI) standards for age and sex. Adults were evaluated according to standard adult values.

RESULTS

Twenty-nine patients (28.2%) were hypertensive or prehypertensive, and 74 (71.8%) were normal. Thirty-eight patients (36.9%) were obese or overweight, and 65 (63.1%) were non-obese. Most Wilms tumor patients, 7 of 10 (70.0%), had hypertension or prehypertension, but only 4 of 10 (40.0%) were obese or overweight.

CONCLUSION

Careful follow-up of their blood pressure status is warranted for long-term survivors of childhood and adolescent cancer, especially for those with an initial diagnosis of Wilms tumor.

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.

[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.

Renal failure in Wilms' tumor patients: a report from the National Wilms' Tumor Study Group

This report defines the incidence and determines the etiology of renal failure (RF) in patients undergoing treatment for Wilms' tumor (WT). The database of the National Wilms' Tumor Study (NWTS) was searched to identify all children reported to have developed chronic renal failure. There were 55 patients found to have RF. Of these, 39 patients had bilateral tumors, 15 with unilateral disease and one with a WT in a solitary kidney. The median interval from diagnosis to the onset of renal failure was 21 months. The incidence of RF in bilateral WT was 16.4% for NWTS-1 & -2, 9.9% for NWTS-3, and 3.8% for NWTS-4. The incidence of RF in unilateral WT remained stable. The most common etiologies of RF were: bilateral nephrectomy for persistent or recurrent tumor (24 pts), Drash syndrome (12 pts), progressive tumor in the remaining kidney (5 pts), radiation nephritis (6 pts), and other causes (5 pts). The etiology of renal failure was not reported in three children. Children with unilateral WT and a normal contralateral kidney have a very low incidence of RF, and this review does not support a recommendation for parenchymal sparing procedures in these patients. Children with bilateral WT are at risk for the development of RF, and parenchymal sparing procedures are warranted.

Nephropathy with Wilms tumour or gonadal dysgenesis: incomplete Denys-Drash syndrome or separate diseases?

We report three children, one presenting with nephropathy, bilateral Wilms tumour (WT) and cryptorchism, one with combined nephropathy and gonadal dysgenesis and one with nephropathy which developed 13 years after a WT. The first case was recognized as typical Denys-Drash syndrome (DDS) which is characterized by the combination of nephropathy, intersex disorders and WT. The two other patients, who did not express the full spectrum of the syndrome, were older than 10 years, when they reached and stage renal failure. The fact that nephropathy in childhood is combined with such rare diseases like gonadal dysgenesis and/or WT, supports the concept of a common aetiology with DDS. Therefore, the patients were analysed for possible Wilms tumour suppressor gene (WT1) mutations. In all three individuals mutations in the heterozygous configuration could be demonstrated.

CONCLUSION

These results provide evidence that incomplete and complete DDS are diseases of the same spectrum. WT1 analysis of more children with two symptoms of the triad of DDS should be helpful in establishing genotype-phenotype correlations and in understanding differences in the clinical picture of DDS.

Effects of treatment for childhood cancer on vital organ systems

Advances in treatment have dramatically increased the survival rate of children and adolescents with cancer. These treatments, however, may be associated with damage to vital organ systems, which may not be evident until many years after the initial diagnosis of cancer and may adversely affect long-term survival and/or the quality of life of former patients. The effects of treatment on three specific organ systems, heart, lungs, and kidneys, are reviewed here.

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 live related kidney donors

Renal function in 12 live kidney donors who had donated a kidney to a relative 3 to 10 years previously was studied. No clinically significant impairment of renal function was observed in the group. A significant rise in creatinine clearance (P = less than 0.01) occurred after a meat-protein load. When compared with 12 healthy controls with two kidneys, there was no significant difference in the percentage change in clearance after the meat load. In both groups there was an inverse correlation between the percentage change in creatinine clearance and the baseline creatinine clearance (P = less than 0.01), with no significant difference in the regression lines of the two groups. In conclusion, it appears that the single kidney responds appropriately to a meat-protein load and that there is no evidence from this study to suggest that hyperfiltration damaged the remaining kidney.

[Terminal renal failure in aniridia-Wilms syndrome]

Missing iris combined with debility and incidence of Wilms' tumor seem to be a complex syndrome which appears in 1:100,000 people. It is caused by an interstitial deletion on the short arm of chromosome no. 11. We refer to a patient who developed end-stage renal failure caused by a focal-segmental nephrosclerosis. He underwent renal transplantation because chronic hemodialysis was impossible due to his lack of compliance. The deletion of chromosome 11 could be recognized by chromosomal analysis after transplantation. An aniridia-Wilms' tumor association (AWTA) with following focal segmental nephrosclerosis could be diagnosed.