Objective To study features of clinical manifestation,pathology and treatment effects of idiopathic membranous nephropathy(IMN).Methods A retrospective study was performed in patients with membranous nephropathy through renal biopsy diagnosis in Beijing Children's Hospital Affiliated to Capital Medical University from November 2009 to February 2013.Patients were diagnosed according to renal biopsy apart from hepatitis B virus-associated glomerulonephritis,Henoch-Schonlein purpura nephritis,lupus nephritis,tumor and drug associated nephritis.The study summed the clinical and pathological features of IMN and evaluated the effect of treatment according the follow up.Results (1) There were 13 patients,with the ratio of male and female being 1.0 ∶ 1.6,among them 1 patient was younger than 6 years old,3 cases were between 6 and 12 years old,and 9 cases were elder than 12 years old.Nine patients were nephrotic syndrome,and 3 patients had renal insufficiency.(2)Ten patients had infection,among them 5 cases were upper respiratory infection with agent unfound,4 patients were mcoplasma infection,1 patient was influenza B virus infection,1 patient had positive result of Hepatitis B surface antibody(HBsAb) and Hepatitis B core antibody (HBcAb),and 2 patients had positive result of purified protein derivative (PPD).(3)Pathological feature of IMN was atypical membranous nephropathy.Atypical membranous nephropathy was characterized by an irregular,thickened glomerular basement membrane(GBM),mesangial cells,and a mesangial matrix with mild to moderate hyperplasia.Immune complexes were stained in the subepithelial region,GBM,and mesangial region under light microscopy.Electron microscopy showed various sizes,density,and shapes of electron-dense deposits in multiple regions.The cases of immunofluorescence were 13 for IgG,10 for C3,9 for IgM,9 for C1q,5 for IgA,2 for C4,and 0 for fibrinogen.Seven patients were strongly positive(3 + and above) for IgG and one patient was strongly positive for C3.(4)Seven patients had complete remission,three patients had partial remission,and three patients had non-remission.Conclusions (1) In this study,children with IMN were mainly girls,and the age distribution was beyond 12 years.Nephrotic syndrome was the most common clinical manifestation.(2)Atypical membranous nephropathy was the most common pathological feature in children with IMN,which should be distinguished from hepatitis B virus-associated glomerulonephritis by testing HBV antigen in renal biopsy.(3) Prednisone was effective for IMN children,but it was suggested to give enough and long course of application.Effect of prednisone combined with cyclophosphamide was still undefined.

Objective:To analyze the ultrasonographic images and clinical characteristics of congenital mesoblastic nephroma (CMN), and to investigate the differential performances with Wilm′s tumor (WT).Methods:Twenty-one cases of CMN patients confirmed by pathology from December 2008 to December 2019 in Beijing Children′s Hospital, Capital Medical University were collected as the CMN group, and in the same criterion, 51 cases of WT patients were taken as WT group. Ultrasonographic images and clinical characteristics were collected retrospectively, and then the tumor size, site, echo and age were compared and analyzed between the two groups. ROC curve was used to evaluate the differential performance.Results:The difference analysis showed that except for echo ( P=0.694), there were statistically significant differences in tumor size, site and age between the two groups (all P<0.05). In prenatal, the incidence of CMN was significantly higher than WT (61.9% vs 3.9%, P<0.001), and the specificity was 96.1%. The median age (interquartile range) of CMN after birth was significantly earlier than WT( Z=-4.044, P<0.001). The area under the ROC was 0.949, the best cutoff was 112.5 days, with a sensitivity of 87.5% and a specificity of 93.9%. Conclusions:It is difficult to distinguish CMN and WT by echo, but the diagnosis performance can be improved through combining tumor size with site, especially age.

Objective To discuss the unique biological,histological and clinical features of pediatric renal cell carcinoma (RCC).Methods A retrospective review and biological analysis of all RCC cases presenting to our hospital from January 1973 to March 2012 was undertaken.Results Twenty-nine RCC pediatric patients (16 boys,13 girls) with mean age of 9.6 (range 2.5-16.0) years were identified.The presentations included hematuria in 17 (58.6％) cases with 3 who developed hematuria after trauma,abdominal mass with hematuria in 3 (10.3％),abdominal mass in 3,abdominal pain in 2,abdominal pain with hematuria in 1,and incidentally finding in 3.The diameter of tumor was from 2.5 cm to 25.0 cm,mean 6.8 cm.According to TNM stage grouping system,16 cases were stage Ⅰ,10 stage Ⅲ,and 3 stage Ⅳ.Xp1 1.2 translocation RCC was identified in 21 patients,clear cell RCC 6,papillary RCC 2.Of the 29 cases,3 patients with the tumor less than 7-cm had nephron-sparing surgery.A 15-cm tumor was incompletely removed in 1 patient and another patient with a 25 cm× 18 cm×15 cm tumor had gross residual.Nephrectomy was performed for the affected kidney in the remaining 24 patients.Twenty-one patients (Xp1 1.2 translocation RCC 13 patients,clear cell RCC 6,papillary RCC only 2) were followed up from 1.5 to 34.0 years,18 were living well (T1N0M0 in 11 cases,T1N1M0 in 2,T2N1M0 in 3,T3N1M0 in 1 and T4N1M1 in 1) and 3 died of recurrence.Conclusions Although RCC is rare in children,pediatric RCC behaves in a distinct fashion compared with adult forms of RCC.Hematuria is the main symptom in pediatric RCC.Xp11.2 translocation RCC is the predominant form,associated with an advanced stage at diagnosis.Nephrectomy is the common treatment for RCC and nephron sparing surgery could be a reasonable option for patients with tumor smaller than 7 cm.For localized RCC (T1-2 N0-1 M0),simple kidney removal surgery is sufficient for treatment without lymph node dissection and postoperative adjuvant treatment.

Objective: To investigate the clinical, pathological features and differential diagnosis of testicular Leydig cell hyperplasia (LCH) . Methods: Clinical data, histological features, immunohistochemical findings, ultrastructural characteristics and follow-up data were analyzed in three cases of LCH. The cases were collected from 2011 to 2014 at Beijing Children′s Hospital. A literature review was performed. Results: Two males (1.8 years and 2.9 years of age) showed isosexual pseudoprecocity with elevated serum testosterone. Imaging study showed bilateral testicular enlargement with multiple small nodules in the parenchyma. Another 13 years-old patient showed male pseudohermaphroditism and cryptorchism. Gross examination showed the bilateral markedly enlarged testis without discrete lesion. Histologically, LCH was seen in both nodular and diffuse patterns without destruction of seminiferous tubules. Adjacent spermatogenesis was noted. Immunohistochemically, the Leydig cells were positive for inhibin, calretinin and Melan A and ultrastructural analysis showed enriched cytoplasmic endoplasmic reticulum. Two cases had followed up for 7 years. One patient was symptom-free and one was stable. Conclusion LCH is a rare benign condition, which is easily misinterpreted as testicular tumor or non-neoplastic diseases. Clinical presentation, imaging study and pathological evaluation are required for the diagnosis.

Consensus ; Hirschsprung Disease ; diagnosis ; Humans

Objective: To investigate the clinicopathological and ultrastructural characteristics of Langerhans cell histiocytosis (LCH) in children. Methods: A total of 345 cases of LCH from the Department of Pathology, Beijing Children Hospital from January 2012 to March 2016 were investigated by hematoxylin-eosin stain, EnVision immunohistochemistry and transmission electron microscopy. Results: The rate of primary clinical diagnosis of LCH in children was 46.0%(210/457). Among 345 patients of LCH, 213 were male and 132 were female, the male to female ratio was 1.6∶1.0, and the median age was 21 months (range from 2 days after birth to 13.3 years). There were total 597 lesions, including bony lesions (258, 43.2%), skin lesions (206, 34.5%) , followed by lymph node (16, 2.7%), lung (28, 4.7%), liver (25, 4.2%) and head-neck (50, 8.4%). Single organ system LCH (SS-LCH) was seen in 295 cases (85.5%) and 50 cases (14.5%) presented with multiple organ system involvement LCH (MS-LCH). There was no significant difference in age and gender between SS-LCH and MS-LCH groups. Regarding sites, more lesions were seen in bone and skin in SS-LCH group, in contrast lymph node, lung, liver and head-neck involvements were often seen in MS-LCH group. Immunohistochemically, the expression of CD1a and Langerin was seen in 99.7% (341/342) and 98.8% (338/342) of the cases respectively. The diagnostic rates by light and transmission electron microscopy were 98.8% (341/345) and 97.4% (112/115) respectively (P>0.05). Conclusions LCH of children occurs predominantly in SS-LCH pattern, frequently involving bone, skin, lymph node, lung and liver and other sites with unique histopathological, immunophenotypical and ultrastructural features. Accurate diagnosis relies on the morphology, immunophenotype and ultrastructural features. Further refinement of specimen processing may improve the accuracy of pathological diagnosis.

investigate the clinical, pathological features and differential diagnosis of testicular Leydig cell hyperplasia(LCH). Methods Clinical data, histological features, immunohistochemical findings, ultrastructural characteristics and follow?up data were analyzed in three cases of LCH. The cases were collected from 2011 to 2014 at Beijing Children′s Hospital. A literature review was performed. Results Two males (1.8 years and 2.9 years of age) showed isosexual pseudoprecocity with elevated serum testosterone. Imaging study showed bilateral testicular enlargement with multiple small nodules in the parenchyma. Another 13 years?old patient showed male pseudohermaphroditism and cryptorchism. Gross examination showed the bilateral markedly enlarged testis without discrete lesion. Histologically, LCH was seen in both nodular and diffuse patterns without destruction of seminiferous tubules. Adjacent spermatogenesis was noted. Immunohistochemically, the Leydig cells were positive for inhibin, calretinin and Melan A and ultrastructural analysis showed enriched cytoplasmic endoplasmic reticulum. Two cases had followed up for 7 years. One patient was symptom?free and one was stable. Conclusion LCH is a rare benign condition, which is easily misinterpreted as testicular tumor or non?neoplastic diseases. Clinical presentation, imaging study and pathological evaluation are required for the diagnosis.

Extrarenal Wilms′ tumor is extremely rare and has no characteristic clinical manifestations. Diagnosis is difficult before surgery, and is often confirmed by histopathology. Comprehensive treatment by surgery, chemotherapy and radiotherapy is currently adopted for such patients, and the overall survival rate can reach about 90%. Here we report a 2-year-old child with Wilms′ tumor in the left scrotum.

Objective To study the clinicopathological and immunohistochemical features , histogenesis and prognosis of pleuropulmonary blastoma ( PPB) in children.Methods PPB specimens from 16 pediatric cases with an age ranging from 1 year and 7 months to 5 years and 3 months ( mean age of 3 years) were retrieved and analyzed by routine histological , immunohistochemical and electron methods.Results Among 16 patients, there were 2 type Ⅰ, 7 type Ⅱ and 7 type Ⅲ PPB cases.Type Ⅰ PPB as multilocular cystic structure , consisted of thin fibrous wall lining the respiratory epithelium , subepithelial primitive blastema or immature mesenchymal cells , with or without rhabdomyoblastic differentiation or cartilage;Type Ⅱ PPB as cystic-solid tumor,comparing with type Ⅰ, consisted of intracystic components with appearance of anaplastic tumor cells.TypeⅢPPB consisted of completely solid mass , the same as the solid region of type Ⅱ, had mixed pattern including blastema ,undifferentiated spindle-cell proliferations and sarcomas.In addition, anaplastic tumor cells and intra-and extra-cytoplasmic eosinophilic globules were also commonly present.Epithelial components in PPB were benign.Immunohistochemical study showed primitive mesenchymal differentiation of tumors.All cases were positive for vimentin , desmin, myogenin and SMA in tumors with skeletal muscle differentiation , S-100 was positive in tumors with cartilage differentiation.All tumors were negative for synaptophysin ,CD99,and CD117.Benign epithelial components were positive for AE1/AE3 and EMA.In 12 cases, electron microscopy revealed few organelles in the primitive mesenchymal cells and rich heterochromatin in mesenchymal cells , the latter also demonstrating cytoplasmic myofilament dysplasia.Nine cases had clinical follow-up ranging from 5 to 48 months, of which 4 patients died.Conclusions PPB is a rare lung neoplasm of children under the age of 6 years,with distinct pathological morphology .PPB may arise from lung or pleura mesenchymal cells and has a poor clinical outcome.