IL-17 aggravates renal injury by promoting podocyte injury in children with primary nephrotic syndrome.

Primary nephrotic syndrome (PNS) is the most common chronic kidney disease in childhood, where podocyte injury is a key factor in the occurrence of kidney disease. In the present study, the expression of IL-17 in renal tissues of patients with PNS and its relationship with podocyte injury were examined. Reverse transcription-quantitative PCR (RT-qPCR), western blot analysis and immunochemistry were used to measure the expression of IL-17 in renal biopsies of patients with ONS, including 9 patients with minimal change nephrotic syndrome (MCNS), 15 patients with mesangial proliferative glomerulonephritis (MsPGN) and 9 patients with focal segmental glomerulosclerosis (FSGS), in addition to 15 normal kidney tissues. IL-17 was found to be highly expressed in the renal tissues from patients with PNS, with the highest expression levels found in tissues from patients with FSGS and the lowest in those from MCNS. A negative correlation was observed between the levels of IL-17 mRNA and PCX mRNA in renal tissues, whereas a positive correlation between IL-17 mRNA levels and the number of urinary podocytes in patients with PNS was found. In vitro, IL-17 induced podocyte apoptosis and reduced the expression of markers associated with podocytes, including Wilm's tumor 1, nephrin, synaptopodin and podocalyxin, whilst increasing the levels of Fas, Fas ligand (FasL), active-caspase-8, active-caspase-3 and phosphorylated-p65. However, treatment with helenalin, a NF-κB inhibitor, decreased p65 phosphorylation, attenuated IL-17-induced podocyte apoptosis and suppressed the IL-17-activated Fas/FasL/caspase-8/caspase-3 apoptotic pathway. Taken together, these observations suggest that IL-17 was highly expressed in renal tissues from patients with PNS, where it induced podocyte apoptosis by activating the Fas/FasL/caspase-8/caspase-3 apoptotic pathway in a NF-κB-dependent manner.

Analysis of misdiagnosed cases of hemorrhagic fever with renal syndrome in children: two cases and literature review.

BACKGROUND: Hemorrhagic fever with renal syndrome (HFRS) is an acute disease caused by hantavirus infection and is clinically characterized by fever, various hemorrhagic manifestations and transient renal and hepatic dysfunctions. Although various cases of HFRS have been reported, cases in children have rarely been described. Herein, we report two atypical cases of HFRS in children without distinctive manifestations and typical disease clinically progresses. CASE PRESENTATION: Patient 1 was a 11-year-old girl who attended our clinic for fever accompanying with acute renal failure, proteinuria and decreased level of complement 3 (C3) and thrombocytopenia without any hemorrhagic manifestations, acute glomerulonephritis was suspected first, especially lupus nephritis. Patient 2 was misdiagnosed as encephalitis at local hospital because of fever and headache for 4 days. With elevated liver transaminases, proteinuria and normal cerebrospinal fluid examination, HFRS was taken into consideration. Both of the two cases were supported and confirmed by serological test for Hantavirus. CONCLUSIONS: Clinical manifestations of HFRS in children often presented atypically and were milder than adults. Febrile disease accompanying with thrombocytopenia may lead to the suspected diagnosis of HFRS.

Interleukin-7 stimulation inhibits nephrin activation and induces podocyte injury.

The glomerular podocytes control filtration barrier permeability in the kidney, and their disturbance underlies the pathogenesis of idiopathic nephrotic syndrome (INS), a kidney disease that predominantly occurs in children. In this study, we found that the interleukin-7 receptor (IL-7R) was induced in the glomeruli of adriamycin (ADR)-induced mouse nephropathy, a rodent model of nephrotic syndrome. In addition, IL-7R was also induced by ADR in mouse podocytes cultured in vitro. Functionally, we discovered that IL-7R activation through the stimulation of recombinant IL-7 induced apoptosis of podocytes, and moreover, IL-7 stimulation inhibited nephrin activation and caused actin cytoskeleton disorganization, indicating that IL-7 stimulation induces podocyte injury. Furthermore, IL-7 stimulation impaired the filtration barrier function of podocyte monolayer. Together, these results identify IL-7 and its receptor IL-7R as potential regulators of podocyte function, which might offer a novel therapeutic target in the treatment of INS.

New PAX2 heterozygous mutation in a child with chronic kidney disease: a case report and review of the literature.

BACKGROUND: We herein report a 3-year-old boy presented with chronic kidney disease (CKD) due to PAX2 missense mutation (C to G transversion at position 418 in exon 4). CASE PRESENTATION: He attended our clinic with a 3-month history of foamy urine. Upon examination, he had reduced estimated glomerular filtration rate (GFR) and renal atrophy. Genetic investigations revealed that he has inherited a mutated PAX2 gene from his father, who had renal failure at the age of 20. We searched the literature and confirmed that this mutation site has not been reported by any other group before. CONCLUSIONS: Although renal coloboma syndrome (RCS) with simultaneous kidney and eye involvement is the most common phenotype of PAX2 mutations, current literature supports that such mutations may have profuse clinical manifestations and renal hypoplasia is one distinct entity in the spectrum.