Clinicopathologic review of twelve children with nephropathy, Wilms tumor, and genital abnormalities (Drash syndrome)

The clinicopathologic and radiologic features of 12 children with complete and incomplete forms of Drash syndrome are reported. Their common denominator was a nephropathy. Four had the full triad, consisting of nephropathy, Wilms tumor, and genital abnormalities; five had nephropathy and genital abnormalities, and three had nephropathy and Wilms tumor. Of the 11 children who had proteinuria, eight had the nephrotic syndrome. Of the 10 whose condition progressed to end-stage renal failure, seven were less than 3 years of age. The histologic features of Wilms tumor were favorable in all seven children, and the tumor was bilateral in three. Of the nine patients who had genital abnormalities, eight had 46,XY karyotype and either ambiguous genitalia (six patients) or normal female phenotype (two). One other patient had a normal 46,XX female karyotype and phenotype but had both müllerian and wolffian structures and a streak ovary. Nine patients had a distinct pelvicaliceal abnormality not previously reported as a feature of this syndrome. Other congenital abnormalities were aniridia, mental retardation, deafness, nystagmus, and cleft palate. This syndrome must be considered in any infant with unexplained nephropathy, particularly in young phenotypic female infants and in those children with ambiguous genitalia or Wilms tumor with an early presentation.     

WT1 gene mutations in three girls with nephrotic syndrome

Denys-Drash syndrome and Frasier syndrome are two related conditions caused by mutations of the Wilms tumor gene, WT1. Both syndromes are characterized by male pseudohermaphrodism, a progressive glomerulopathy, and the development of genitourinary tumors. This study examines three girls with steroid-resistant nephrotic syndrome related to mutations in the WT1 gene, but with normal 46, XX karyotype and normal female phenotype. WT1 mutation analysis should be routinely done in females with steroid-resistant nephrotic syndrome.     

Management of Wilms tumors in Drash and Frasier syndromes

Background

Children with WT1 gene‐related disorders such as Denys–Drash syndrome (DDS) and Frasier syndrome (FS) are at increased risk of Wilms tumor and end‐stage renal disease. We investigated whether Wilms tumors in these patients displayed a specific phenotype or behavior and whether nephron‐sparing surgery was beneficial.

Procedure

We retrospectively studied all patients with DDS, FS, or other WT1 mutations treated at our institutions between 1980 and 2007.

Results

We identified 20 patients, of whom 18 had benign or malignant tumors. Wilms tumors occurred in 15 patients, being unilateral in 10 and bilateral in 5 (20 tumors). Median age at Wilms tumor diagnosis was 9 months. No patients had metastases. According to the International Society of Pediatric Oncology Working Classification, there were 19 intermediate‐risk tumors and one high‐risk tumor; no tumor was anaplastic. In patients with nephropathy who underwent unilateral nephrectomy for Wilms tumor or nephron‐sparing surgery for bilateral Wilms tumor, mean time to dialysis was 11 or 9 months, respectively. Other tumors included three gonadoblastomas (in two patients), one retroperitoneal soft‐tissue tumor, and one transitional cell papilloma of the bladder. Two patients, both with stage I Wilms tumor, died from end‐stage renal disease‐related complications. The median follow‐up time for the 18 survivors was 136 months (range, 17–224 months).

Conclusion

Most Wilms tumors in children with WT1‐related disorders were early‐stage and intermediate‐risk tumors, with a young age at diagnosis. In patients without end‐stage renal disease, nephron‐sparing surgery should be considered for delaying the onset of renal failure. Pediatr Blood Cancer 2009;52:55–59. © 2008 Wiley‐Liss, Inc.     

Focal segmental glomerulosclerosis with and without nephrotic syndrome in children

The clinical presentation, initial laboratory and renal biopsy findings, and course of focal segmental glomerulosclerosis (FSGS) were studied retrospectively in 57 children in order to compare findings in those with and without nephrotic syndrome and to establish factors of prognostic significance. All patients had proteinuria. Eleven patients were otherwise asymptomatic, and nephrotic syndrome did not develop (group 1); 14 patients had asymptomatic proteinuria, but nephrotic syndrome subsequently developed (group 2); 32 patients had nephrotic syndrome (group 3). There were no differences between these three groups with regard to sex, age, initial renal function, incidence of hypertension and hematuria, and pathologic findings. At the latest follow-up, five group 1 patients, six in group 2, and 14 in group 3 had chronic renal failure; the incidence was similar for those with asymptomatic proteinuria and those with nephrotic syndrome. The location of the sclerosis within the glomerulus proved to have prognostic significance. All 12 patients with peripheral FSGS maintained normal renal function, whereas in 25 of the 44 with hilar FSGS chronic renal failure developed.     

Nephrotic Syndrome

The pathogenetic basis of idiopathic nephrotic syndrome, a common childhood glomerulopathy, is being explored. While initial evidence supported an imbalance of T helper responses, recent studies suggest alterations in both innate and adaptive immune responses, including evidence for impaired T regulatory function. The central role of the podocyte in causing proteinuria is confirmed by the observation of mutations in key podocyte proteins in steroid resistant nephrotic syndrome and experimental evidence of altered podocyte signaling and cytoskeletal organization. The outcome and management of idiopathic nephrotic syndrome in children is determined by the response to corticosteroids and the frequency of relapses. While patients with steroid sensitive nephrotic syndrome have a favorable long term outcome, almost half of them relapse frequently and are at risk of adverse effects of corticosteroids. Although various non-corticosteroid immunosuppressive agents are used to prolong disease remission, careful monitoring is required for the potential adverse effects. Calcineurin inhibitors have emerged as the choice of therapy in patients with steroid resistant nephrotic syndrome. However, the management of this form of the disease is particularly challenging because of the variable response to immunosuppression, therapy-related significant adverse effects and high rates of disease progression to end stage renal disease. Patients with both corticosteroid sensitive and resistant forms of the disease are at risk of complications of disease, and require close monitoring and repeated counseling.     

Denys-Drash syndrome with neonatal renal failure in monozygotic twins due to c.1097G>A mutation in the WT1 gene

Denys-Drash syndrome, characterized by nephrosis, dysgenetic gonads and a predisposition to Wilms tumor, is due to germline mutations in the WT1 gene. We report the pathologic findings on monozygotic twins, both of whom presented with male pseudohermaphroditism, nephrotic syndrome, and progressed to renal failure and death within the first month of life. Sequence analysis of WT1 demonstrated a G-to-A substitution in exon 8 of the gene (c.1097G > A), resulting in an arginine-to-histidine (R366H) substitution in the second zinc finger domain. To the best of our knowledge, this is only the second set of monozygotic twins with Denys-Drash syndrome reported to date.     

Successful pulmonary artery embolectomy in a patient with a saddle Wilms tumor embolus

Denys-Drash syndrome is a genetic disorder characterized by ambiguous genitalia, cryptorchidism, nephrotic syndrome, and a high predilection for Wilms tumor with intravascular invasion. We report a 5-year-old male with Denys-Drash syndrome who rapidly developed Wilms tumor with vascular invasion, subsequent saddle tumor embolus, and required emergent embolectomy. This case illustrates the rapid emergence of Wilms tumor in a patient with Denys-Drash syndrome and the importance of considering embolectomy over thrombolytic therapy for PE in this population, given a high likelihood of tumor embolus.     

WT1基因检测时机对Wilms肿瘤合并慢性肾脏疾病预后影响的回顾性队列研究

目的 分析在Wilms肿瘤合并慢性肾脏疾病(CKD)的患儿中WT1基因检测对诊断和长期预后的影响。方法 检索上海市肾脏发育与儿童肾脏病研究中心儿童肾脏病基因检测数据库,2001年1月1日至2018年12月31日明确WT1基因突变、年龄<18岁患儿,或Wilms肿瘤合并CKD 2~5期或肾病综合征或有蛋白尿的连续病例。按进展为终末期肾衰竭(ESRD)之前是否明确WT1基因突变分为早诊断组和晚诊断组,以ESRD为终点比较两组的预后。结果 22例患儿明确WT1基因的常染色体显性遗传突变,分别位于第8~9外显子/内含子。依据临床分型,10例为Denys-Drash综合征,3例为Fraiser综合征,9例表型为孤立型肾病综合征,5例合并假两性畸形。随访终点进入ESRD有15例,7例进入CKD 2~4期。应用生存曲线分析证实,早诊断组较晚诊断组进入ESRD病程显著延迟(P=0.011)。结论 在儿童Wilms肿瘤、肾病综合征/蛋白尿、慢性肾功能损害的患儿中,在肾功能进展恶化之前及早明确WT1基因突变,不仅有助于临床诊断分型,还能显著延缓进入ESRD病程。     

WT1基因检测时机对Wilms肿瘤合并慢性肾脏疾病预后影响的回顾性队列研究

目的 分析在Wilms肿瘤合并慢性肾脏疾病(CKD)的患儿中WT1基因检测对诊断和长期预后的影响。方法 检索上海市肾脏发育与儿童肾脏病研究中心儿童肾脏病基因检测数据库,2001年1月1日至2018年12月31日明确WT1基因突变、年龄<18岁患儿,或Wilms肿瘤合并CKD 2~5期或肾病综合征或有蛋白尿的连续病例。按进展为终末期肾衰竭(ESRD)之前是否明确WT1基因突变分为早诊断组和晚诊断组,以ESRD为终点比较两组的预后。结果 22例患儿明确WT1基因的常染色体显性遗传突变,分别位于第8~9外显子/内含子。依据临床分型,10例为Denys-Drash综合征,3例为Fraiser综合征,9例表型为孤立型肾病综合征,5例合并假两性畸形。随访终点进入ESRD有15例,7例进入CKD 2~4期。应用生存曲线分析证实,早诊断组较晚诊断组进入ESRD病程显著延迟(P=0.011)。结论 在儿童Wilms肿瘤、肾病综合征/蛋白尿、慢性肾功能损害的患儿中,在肾功能进展恶化之前及早明确WT1基因突变,不仅有助于临床诊断分型,还能显著延缓进入ESRD病程。     

1 316例小儿肾脏病临床与病理分布特点

目的：了解小儿肾小球疾病肾脏病理改变的特点及其与临床表现的关系。方法：对近20年间该院的1 316例患儿的肾活检资料,进行了回顾性分析。结果：1 316例患儿中临床主要表现为肾病综合征(383例,占29.09% )、急性肾炎综合征(291例,占22.00%)、孤立性血尿(224例,占17.21%)、紫癜性肾炎（209例,占15.87%）、乙型肝炎病毒相关肾炎(96例,占7.30% )等。病理改变主要为系膜增生(756例,占57.45%)、IgA肾病(113例,占8.59% )、毛细血管内增生（112例,占8.51%）、膜性肾病(66例,占5.02%)、微小和轻微病变(59例,占4.48%)等。通过超微结构检查,使Alport综合征、薄基底膜病、先天性肾病、纤维样肾小球病、Fabry病等,得以明确诊断。通过肾活检组织免疫病理学检查,使IgA肾病、IgM肾病及C1q肾病得以确诊。肾活检患儿中原发性肾小球疾病最为常见（915例,占69.53%）。原发性肾小球疾病病因以原发性肾病综合征为最常见（375/915例,占41.0%）,而继发性肾小球疾病病因以紫癜性肾炎为最常见（209/344例,占60.8%）。结论： 在该次调查的肾活检资料中,原发性肾小球疾病最常见,肾病综合征是最常见的临床诊断,病理改变则以系膜增生最为多见。［中国当代儿科杂志,2007,9（2）：117-121］     

Pretreatment, ultrasound-guided cutting needle biopsies in childhood renal tumors

BACKGROUND: The current International Society of Paediatric Oncology (SIOP)-10 protocol does not allow pretreatment histological classification of low-stage renal tumors in children for fear of needle tract recurrences. The aims of this retrospective study were to evaluate the safety, sensitivity, and specificity of ultrasound-guided cutting needle biopsies (UCNB) performed at our institution in pediatric patients with renal tumors. PROCEDURE: Of 28 pediatric patients presenting with a renal tumor between 1988 and 1996, 25 underwent biopsy with the Biopty biopsy instrument (needle diameter 1.2 mm). The preoperative biopsy and nephrectomy slides were reviewed by a SIOP reference pathologist. The patients' hospital records were reviewed and biopsy complications were noted. RESULTS: At review of the nephrectomy slides, the diagnoses were: Wilms tumor (16 patients), with anaplasia in one case, rhabdoid tumor (2 patients), neuroblastoma (2 patients), mesoblastic nephroma (2 patients), clear cell sarcoma (1 patient), malignant teratoma (1 patient), and renal cell carcinoma (1 patient). No needle tract recurrence or other major complication was observed. The only complication was local pain at the biopsy site, which occurred in 24% (6/25) of the cases. The sensitivity of UCNB was 76% (19/25); five biopsies did not yield diagnostic material and one was not concordant. All cases of Wilms tumor were correctly diagnosed by UCNB, but only 33% (3/9) of the other tumors. CONCLUSIONS: In all cases of Wilms tumor a correct diagnosis was made. The overall sensitivity was 76%. UCNB proved to be a safe procedure that was not associated with needle tract recurrence or other serious complications.     

Nephropathy gonadal dysgenesis--or incomplete Drash syndrome?]

This is a report about a phenotypical normal girl with nephropathy and gonadal dysgenesis. At the age of 2 years 8 months she presented with steroid resistant nephrotic syndrome. Focal segmental glomerulosclerosis was found by biopsy. Because of delayed puberty karyotyping was performed, which revealed 46 XY. Thirteen years after onset of proteinuria she reached end stage renal failure. Gonadal dysgenesis and nephropathy are often indistinguishable from incomplete Drash syndrome. Children with early nephropathy of unknown origin or gonadal dysgenesis should be observed for development of Wilms tumor. When chronic nephropathies are present in girls, karyotyping should be considered.     

Collapsing Glomerulopathy in a 16-Year-old Girl with Pulmonary Tuberculosis: The Role of Systemic Inflammatory Mediators

Idiopathic collapsing glomerulopathy is an aggressive variant of focal segmental glomerulosclerosis (FSGS) seen primarily in adults. Its etiology is unknown. Nearly identical pathology is seen in association with nephrotic syndrome in human immunodeficiency virus type 1 (HIV-1)-infected patients, raising the possibility that viral infection plays a role in pathogenesis. This is supported by the recent discovery of parvovirus B19 DNA in some cases of idiopathic collapsing glomerulopathy. We report a case of collapsing glomerulopathy in a 16-year-old girl who presented with steroid-resistant nephrotic syndrome and pulmonary tuberculosis. In the absence of the usual associations (adult age group, African-American race, or history of intravenous drug abuse), infection is the sole known risk factor in this case. This lends support to the hypothesis that immune dysregulation due to infection per se, rather than infection by specific viral agents, may lead to collapsing glomerulopathy in susceptible individuals.     

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. Pediatr Blood Cancer 2013;60:1929–1935. © 2013 Wiley Periodicals, Inc.     

Management of pediatric renal tumor: Past and future trials of the Japan Wilms Tumor Study Group

The Japan Wilms Tumor Study group (JWiTS) was founded in 1996 to improve outcomes for children with renal tumor in Japan, and a nationwide multicenter cooperative study was initiated thereafter. JWiTS‐1 (1996–2005) was analyzed, and JWiTS‐2 (2005–2014) is now under analysis; the following problems have been identified and used to decide future study protocol: (i) there has been a decline in survival rate for patients with rhabdoid tumor of the kidney (RTK) and new treatment strategies are required; (ii) the survival rate for bilateral Wilms tumors (BWT) has improved, but results for renal preservation are unsatisfactory; (iii) the prognosis of stage IV favorable nephroblastoma is very good, suggesting that the current protocols provide overtreatment, particularly for patients with lung metastasis; and (iv) no effective biological risk factors exist for predicting the outcome of Wilms tumor, and a study of the genetic changes of these tumors is necessary to determine biological markers for use in risk classification. To solve these issues, the development of a new risk classification of pediatric renal tumors is required. In addition, different study protocols should be developed according to the risk‐based classification of the patients. Further, a new study protocol for BWT began in 2015, and new study protocols are being prepared for RTK, and for Wilms tumor with lung metastasis. In addition, an analysis of biological markers with regard to risk classification is to be performed. Furthermore, to create new protocols for patients with rare renal tumors, international collaboration with Children's Oncology Group and International Society of Pediatric Oncology is necessary.     

Lupus nephritis. Collaborative study by the French Society of Paediatric Nephrology.

Sixty two children were included in a collaborative study to determine the prognosis for lupus nephritis. Renal involvement was confirmed by histologic study of renal biopsy specimens which were classified into five categories: minimal lesions (11 cases, 18%); focal segmental glomerulonephritis (15, 24%); diffuse proliferative glomerulonephritis (30, 48%); membranous nephropathy (5, 8%); and glomerular sclerosis (1,2%). That the predictive value of the early biopsy is limited was indicated by the most recent status of 37 patients five years after onset--total remission (13, 35%); urinary abnormalities or nephrotic syndrome (7, 19%); moderate renal failure (4, 11%); chronic renal failure (7, 19%); and hypertension (6, 16%). Treatment did not always prevent the development of severe renal failure; in particular, plasmapheresis failed to avert the death of one patient and the development of chronic renal failure in two others.     

Congenital and infantile nephrotic syndrome in Thai infants

Congenital and infantile nephrotic syndrome reported from the Eastern world is rare and might be a different entity from that in the West. In a retrospective review of 10 nephrotic syndrome in Thai infants (5 girls and 5 boys), 7 were diagnosed with congenital nephrotic syndrome and 3 with infantile nephrotic syndrome. Two had congenital nephrotic syndrome secondary to congenital syphilis. All had edema, ascites, and failure to thrive. Of the 3 patients tested for thyroid function, all showed hypothyroidism. Two patients developed renal failure. Renal tissue was examined from 4 patients from 3 biopsies and 2 autopsies; only 1 patient showed tubular microcysts. Symptomatic therapy was performed concurrently with penicillin therapy in 2 patients having congenital syphilis. Prednisolone, cyclophosphamide, captopril, and enalapril were tried in some patients, with little effect. Five patients died from respiratory failure complicated by later infection, 1 patient died from renal failure, and 4 patients were lost to follow-up. Nephrotic syndrome in the first year of life in the Eastern world is rare. Prognosis of nephrotic syndrome in Thai infants at this time is still poor.     

DIAGNOSIS OF CONGENITAL NEPHROTIC SYNDROME: A CLINICAL AND A PATHOLOGIC CHALLENGE

The diagnosis of congenital nephrotic syndrome (NS) is a challenge both for clinicians and for pathologists. We observed three cases in a series of 50 children with NS nonresponsive to therapy, corresponding to one case each of minimal change disease, Finnish-type glomerulopathy, and diffuse mesangial sclerosis--two histopathologic studies were performed in each case. The age at presentation did not predict the diagnosis nor the prognosis: The NS presented at 7 months of age in the patient with diffuse mesangial sclerosis, but it was present at birth in the patient with minimal change disease. In these 2 patients the final diagnosis was made with the first renal biopsy. Conversely, in the patient with Finnish-type glomerulopathy, the diagnosis was only possible in the repeat biopsy, as the early pathologic changes were nonspecific. This study shows the essential role of the renal biopsy in determining the etiologic diagnosis and prognosis in patients with congenital nephrotic syndrome.     

Left atrial atheromatosis in childhood nephrotic syndrome

Three male children who had onset, at approximately age 2 years, of nephrotic syndrome, which progressed to renal insufficiency had left atrial atheromatosis at autopsy disproportionate to the degree of aortic or vascular atheromatosis found. The atrial atheromatous process was distributed in elongated nodules, which had a ridged or corduroy-like appearance on gross examination. Two of the patients showed renal lesions of advanced focal glomerulosclerosis, but one had membranoproliferative glomerulopathy, suggesting that the "syndrome" of early onset nephrotic syndrome progressing to renal insufficiency, hyperlipidemia, and exaggerated left atrial atheromatosis, of which association we have not found a specific report, is etiologically heterogeneous. The patients reported died in 1943, 1952, and 1963. Whether more recent methods of treatment of nephrotic syndrome, hyperlipidemia, or chronic renal insufficiency in children have altered the incidence of such disproportionate left atrial atheromatosis is not known.     

Results of the SIOP 93-01/GPOH trial and study for the treatment of patients with unilateral nonmetastatic Wilms Tumor

BACKGROUND: The treatment of Wilms Tumor is integrated into clinical trials since the 1970's. In contrast to the National Wilms Tumor Study Group (NWTSG) the SIOP trials and studies largely focus on the issue of preoperative therapy to facilitate surgery of a shrunken tumor and to treat metastasis as early as possible. PATIENTS AND METHODS: In the SIOP 93-01/GPOH trial and study 1 020 patients with a newly diagnosed renal tumor were registered. 847 of them had a histological proven Wilms Tumor, of whom 637 were unilateral localized, and 173 tumors had an other histology [40 congenital mesoblastic nephroma (CMN), 51 clear cell sarcoma (CCSK), 24 rhabdoid tumor (RTK) and 58 other tumors]. Preoperative chemotherapy in benign tumors was given to 1.3 % of the patients. The main objective of the trial was the randomized question, if the postoperative two drug chemotherapy for stage I in intermediate risk or anaplasia can be reduced from conventional 3 courses to an experimental 1 course without loss of efficacy. RESULTS: 519 patients with unilateral nonmetastatic Wilms did receive preoperative chemotherapy. The histology in this group of patients was of intermediate risk in 469 (90 %) patients, 14 (3 %) tumors were low risk and 36 (7 %) high risk. The stage distribution of the tumors was stage I in 315 (61 %), stage II N- in 126 (24 %), stage II N+ in 25 (5 %) and stage III in 36 (7 %) patients. In 17 (3 %) patients the tumor stage remained unclear. Tumor volume was measured in 487 patients before and in 402 after preoperative chemotherapy. The median tumor volume did shrink from 353 to 126 ml. The amount of volume reduction depends on the histological subtype. The event free survival (EFS) after 5 years was 91 % for all patients with unilateral Wilms tumor without distant metastasis. Randomisation was done in 43.7 % for stage I patients and there was no difference in EFS for both treatment arms (90 versus 91 %). The EFS is identical for patients with stage I and II N- (0.92), as well as for stage II N+ and III (0.82). The tumor volume after chemotherapy is a prognostic factor for intermediate risk tumors with the exception of epithelial and stromal predominant tumors. These two subtypes often present as large tumors, they do not shrink during preoperative chemotherapy but they still have an excellent prognosis. On the other hand the prognosis of patients with blastemal predominant subtype after preoperative chemotherapy is worse than in any other patient group of intermediate risk tumors. There are less blastemal predominant tumors compared to primary surgery, but they are chemotherapeutic resistant selected by the preoperative chemotherapy. CONCLUSION: Patients with unilateral Wilms tumor without metastasis have an excellent prognosis. The post-operative chemotherapy in stage I can be reduced to 4 weeks without worsening treatment outcome. The reduction of the tumor volume could be identified as a helpful marker for stratification of post-operative treatment. Post-chemotherapy blastemal predominant subtype of Wilms tumor has to be classified as high risk tumor. Focal anaplasia has a better prognosis than diffuse anaplasia and will be classified as intermediate risk tumor.