Noboru Tsuru

Nephropathy of Nail-Patella Syndrome

Ultrastructural renal lesions of a sporadic case of nail-patella syndrome are described. Although the patient, an 8-year-old Japanese boy, had no clinical renal syndrome, electron microscopy disclosed the presence of collagen fibrils and electron lucent areas within glomerular basement membrane. Comparative observation of glomeruli in sections stained by uranyl-acetate and lead-citrate and those by PTAH-uranyl revealed evidence of many collagen fibrils in mesangial matrix, as well as glomerular basement membrane. At the follow-up study 3 years after the biopsy, he still showed normal urinalysis and no renal dysfunction. Characteristic ultrastructure of glomerulus of this disease can be present even in cases without any apparent clinical renal involvement. It is concluded that the glomerular lesions in nail-patella syndrome may be caused by abnormal metabolic processes of collagen in glomeruli rather than entrapment of circulating collagen precursors.

Association of DQB1*0302 Alloantigens in Japanese Pediatric Patients with Steroid-Sensitive Nephrotic Syndrome

We identified human leukocyte alloantigens (HLA) class II alleles in 24 Japanese children with steroid-sensitive nephrotic syndrome (SSNS) by deoxyribonucleic acid (DNA) typing. The DQA1 and DQB1 alleles were identified using sequence-specific oligonucleotide probes for DQA and DQB. The frequency of DQB1*0302 was significantly higher in the patients than in the controls (54.0 vs. 16.0%, respectively; relative risk, RR = 6.2; pc < 0.00009. We also found that the frequency of DQA1*0103 in the patients was significantly lower than in the controls (RR = 0.194, pc < 0.04). Several studies have identified an association between certain HLA by serotyping. In the present study, we investigated the HLAs of Japanese patients with SSNS by DNA typing and observed a significant increase in the frequency of DQB1*0302 in patients with the disease. HLA-DQ3, which was proven to be associated with SSNS, consists of HLA DQ7, 8 and 9. DQB1*0302 is a component of HLA-DQ8. So we proposed the increase of DQ3 was due to an increase in DQ8.

Fibronectin glomerulopathy with nephrotic syndrome in a 3-year-old male

Abstract Familial non-immune-mediated glomerulopathy has recently been recognized as a distinct clinical entity. The presentation includes proteinuria, often in the nephrotic range, microscopic hematuria, and hypertension. Renal function may remain intact long term, or may progress slowly to renal failure. A 3-year-old boy was referred with proteinuria (>8 g/day), microscopic hematuria, and hypertension (184/150 mmHg). Renal function was intact. Diagnostic evaluation uncovered no evidence of systemic disease. A renal biopsy specimen showed no immune deposits in the glomeruli, but fibronectin deposits were detected in the peripheral loop and mesangium by immunofluorescence. The basement membrane was intact. Twelve other family members subsequently were found to have some renal pathology. Renal function was preserved during 7 years of follow-up. The pathogenesis of fibronectin glomerulopathy is discussed.

Clinicopathological correlation of childhood IgA glomerulonephritis presenting diffuse endocapillary proliferation.

The aim of the present study is to clarify the clinicopathological correlation of childhood IgA glomerulonephritis (GN) presenting diffuse endocapillary proliferation. Twenty‐seven patients were used in the present study. The 27 patients were divided into three groups (mild, moderate and severe) according to the percentage of glomeruli displaying global endocapillary proliferation per total glomeruli at the first biopsy. The degree of both cellular crescent and lysis of the glomerular basement membrane (GBM) at the first biopsy was semiquantitatively evaluated. The degree of cellular crescent and lysis in the GBM was greater in the severe group than in the mild group. The degree of lysis of the GBM positively correlated with the degree of distribution of endocapillary proliferation. The degree of glomerular sclerosis at the second biopsy was greater in the severe group compared with the other two groups. The severity of cellular crescent at the first biopsy positively correlated with that of glomerular sclerosis at the second biopsy. Multiple logistic regression analysis indicated that the risk of glomerular sclerosis at the second biopsy was 19‐fold higher in the odds ratio in the severe group compared with the mild group. In conclusion, the progression of glomerular sclerosis in serial biopsy is dependent on the degree of distribution of endocapillary proliferation and the severity of cellular crescents at the first biopsy in childhood IgA GN presenting diffuse endocapillary proliferation.

Epidemiologic Survey of Children with End‐Stage Renal Disease

We performed an epidemiologic study on the basis of a questionnaire survey of 162 children with end‐stage renal disease (ESRD). Sixty‐nine (43%) of our 162 children, including 25 detected at mass screening of urine, were found by chance hematuria and/or proteinuria. The three major causes of ESRD in our children were chronic glomerulonephritis (CGN) in 56, congenital anomalies of the urinary tract in 30, and nephrotic syndrome (NS) in 27. The renal pathology in 39 children with CGN or NS was focal glomerular sclerosis in 15, diffuse mesangial GN in 7, IgA GN in 5, membranoproliferative GN in 3, membranous GN in 3, and unclassified in 6. Forms of dialysis initiated were hemodialysis in 91 children, continuous ambulatory peritoneal dialysis (PD) in 66, and intermittent PD in 5. Renal transplantation was performed on 38 children, and the graft and the patient survival rates were 76% and 89%, respectively. The survival rate of our 162 children for a mean follow‐up of 8.1 years was 77%. In conclusion, an integrated program of maintenance dialysis and transplantation provides a favorable life for children with ESRD.

髄液より特異DNAが検出され, interleukin-6が高値を示したマイコプラズマ脳炎の1小児例

A 9-year-old female was admitted to our hospital due to a generalized seizure and consciousness disturbance. The patient had a fever and rash four days before admission, but she had no respiratory symptoms. The seizure and consciousness disturbance was prolonged and intractable. We diagnosed the patient as having encephalitis because of the increase in the cell count in the cerebrospinal fluid (CSF) and a diffuse slow EEG wave. The computed tomography of the head was normal. The causative agent was identified as Mycoplasma pneumoniae because of the increase of antibodies, and the detection of a specific DNA with a polymerase chain reaction. The interleukin (IL)-6 level of CSF was high (384 pg/ml). In spite of intensive treatment she had severe neurological sequelae. The invasion of Mycoplasma pneumoniae to the central nervous system appeared to have a role in the development of encephalitis in the patient. We speculated that there is a possible relationship between the IL-6 levels of CSF and clinical severity of encephalitis.

Comparison of asymptomatic and symptomatic childhood glomerulonephritis progressing to renal failure: a report of Kyushu Pediatric Nephrology Study Group

We evaluated the clinicopathological features and the outcome of 33 children with primary glomerulonephritis (GN) as the cause of renal failure; 17 had asymptomatic (ASP) haematuria and/or proteinuria and the remaining 16 had symptoms suggestive of GN. The renal histology in the ASP group indicated IgA GN in 6 children, focal segmental glomerular sclerosis (FSGS) in 4, diffuse proliferative GN (DPGN) in 3, membranous GN (MGN) in 1, membranoproliferative GN (MPGN) in 1 and diffuse sclerosing GN in 2. In the symptomatic (SYP) group, FSGS was evident in 9 children, DPGN in 3, MGN in 2, IgA GN in 1 and MPGN in 1. There was no difference in the histological severity between the two groups. Fourteen children in the SYP group had nephrotic syndrome (NS) and/or hypertension at their initial visits. Only 4 children in the ASP group showed NS or hypertension during the period of follow-up. Eleven children in the ASP group and all in the SYP group were treated with immunosuppressive and/or antihypertensive drugs, but these did not improve the prognosis of the ASP children compared with those in the SYP group. There was no significant difference in the mean duration between the onset of the disease and the start of dialysis in these two groups. In conclusion, it is questionable whether the urinary mass screening programme in Japan will alter the outcome of children with GN.

A Case of Bilateral Renal Dysplasia with Dandy-Walker Syndrome and Tapetoretinal Degeneration

We treated a 5 year and 9 month old Japanese boy, with symptoms of congenital blindness due to tapetoretinal degeneration and Dandy‐Walker syndrome who died of renal insufficiency. The autopsy findings of the kidney revealed bilateral dysplasia with cysts. These findings were compared to similar abnormalities occurring simultaneously in the eye, brain and kidney (oculocerebro‐renal syndrome) which has been considered as a new syndrome.