This study is the first report in which the relationship between the progression of renal involvement in Henoch-Schönlein purpura (HSP) and various factors was evaluated using a multivariate analysis. Sixty-five (33.5%) of 194 patients with HSP developed renal involvement from three days to 17 months after the onset of the disease. The plasma coagulation factor XIII (F XIII) activity of 97 patients was examined, and 51 (54.3%) of them showed a decreased activity. A univariate analysis showed that an age at the onset of more than seven years, persistent purpura and a decreased F XIII activity all increased the risk of developing renal involvement. A Cox regression model analysis indicated severe abdominal symptoms, persistent purpura and decreased F XIII activity to be significant risk factors and their hazard ratios were 3.26, 11.53 and 2.27, respectively. Corticosteroid treatment had a hazard ratio of 0.36 and was considered to decrease the risk of developing renal involvement. Based on these findings, patients who have the risk factors for renal involvement should be treated with corticosteroids at the onset of the disease to prevent developing renal involvement.

These studies demonstrate that mutation of NPHS1 is not a major cause of CNS in Japanese patients, and that mutation of NPHS2 can be responsible for CNS in this population.

No abstract

To understand the genetics of steroid-sensitive nephrotic syndrome (SSNS), we conducted a genome-wide association study in 987 childhood SSNS patients and 3,206 healthy controls with Japanese ancestry. Beyond known associations in the HLA-DR/DQ region, common variants in NPHS1-KIRREL2 (rs56117924, P[4.94E-20, odds ratio (OR) [1.90)

Nephrotic syndrome is the most common cause of chronic glomerular disease in children. Most of these patients develop steroid-sensitive nephrotic syndrome (SSNS), but the loci conferring susceptibility to childhood SSNS are mainly unknown. We conducted a genome-wide association study (GWAS) in the Japanese population; 224 patients with childhood SSNS and 419 adult healthy controls were genotyped using the Affymetrix Japonica Array in the discovery stage. Imputation for six genes (, ,, , and) was conducted on the basis of Japanese-specific references. We performed genotyping for /- using a sequence-specific oligonucleotide-probing method on a Luminex platform. Whole-genome imputation was conducted using a phased reference panel of 2049 healthy Japanese individuals. Replication was performed in an independent Japanese sample set including 216 patients and 719 healthy controls. We genotyped candidate single-nucleotide polymorphisms using the DigiTag2 assay. The most significant association was detected in the region and replicated (rs4642516 [minor allele G], combined=7.84×10; odds ratio [OR], 0.33; 95% confidence interval [95% CI], 0.26 to 0.41; rs3134996 [minor allele A], combined =1.72×10; OR, 0.29; 95% CI, 0.23 to 0.37). (=1.82×10; OR, 2.62; 95% CI, 1.94 to 3.54) and (=2.09×10; OR, 0.10; 95% CI, 0.05 to 0.21) were considered primary alleles associated with childhood SSNS. (=7.01×10; OR, 3.60; 95% CI, 2.46 to 5.29) was identified as the most significant genetic susceptibility factor. The most significant association with childhood SSNS was detected in the region. Further allele/haplotype analyses should enhance our understanding of molecular mechanisms underlying SSNS.