Immune profile and Epstein-Barr virus infection in acute interstitial nephritis: an immunohistochemical study in 78 patients

Epstein-Barr virus-related hemophagocytic lymphohistiocytosis complicated with coronary artery dilation and acute renal injury in a boy with a novel X-linked inhibitor of apoptosis protein (XIAP) variant: a case report

Background

X-linked lymphoproliferative disease (XLP) is a rare inherited X-linked primary immunodeficiency diseases (PID). One such disease, X-linked inhibitor of apoptosis protein (XIAP) deficiency, is characterized by Epstein–Barr virus-related hemophagocytic lymphohistiocytosis (EBV-HLH). However, EBV-HLH with coronary artery dilation and acute renal injury (AKI) in children is unusual.

Case presentation

We report the case of a young boy aged 17 months with a novel XIAP variant. He was initially diagnosed with EBV-HLH based on the HLH-2004 diagnostic criteria and the condition was accompanied by coronary artery dilation and acute renal injury. The comprehensive genetic analysis of peripheral blood-derived DNA revealed a hemizygous variant of the XIAP gene [c.116G > C(p.G39A)], which was inherited from his mother (heterozygous condition). After combined treatment with rituximab, intravenous immunoglobulin, corticosteroids, antiviral drugs, and mycophenolate mofetil (MMF) in addition to supportive therapy, his clinical manifestations and laboratory indexes were improved. The patient achieved complete remission with MMF treatment in the 8-month follow-up.

Conclusions

We report the [c.116G > C(p.G39A)] variant in the XIAP gene for the first time in a case of XLP-2 associated with EBV-HLH. For male patients with severe EBV-HLH, the possibility of XLP should be considered and molecular genetic testing should be used early in auxiliary diagnosis. Reports of EBV-HLH with coronary artery dilation and AKI in children are rare. In the patients with EBV-HLH, color Doppler echocardiography and urine tests should be monitored regularly. If necessary, renal biopsy can be performed to clarify the pathology. Treatment with rituximab, immunosuppressors and supportive therapy achieved a good effect, but long-term follow-up is required.

Acute kidney injury in an adult patient with IgA nephropathy and chronic replicative Epstein-Barr virus infection

Most of the adult population are infected with Epstein-Barr virus (EBV), but as EBV replication is usually under immune system control, the majority of individuals remain asymptomatic. On the other hand, some individuals continuously retain a high EBV antibody titer and a high EBV DNA load in their blood, suggesting a defect of EBV replication control. To date, only a limited number of reports have addressed the relationship between this chronic form of EBV infection and renal involvement. Here, we describe an 80-year-old woman who developed acute kidney injury shortly after an episode of mosquito bites, accompanied by a severe skin rash, which raised a suspicion of chronic EBV infection. She was subsequently diagnosed as having chronic replicative EBV infection. Renal biopsy revealed a diagnosis of IgA nephropathy with crescent formation. Although the relationship between IgA nephropathy and EBV infection has been discussed, no substantial understanding has yet emerged. The patient's characteristic clinical course suggested that the renal failure may have been partly attributable to chronic EBV infection. This case suggests that physicians may need to consider the possibility that chronic EBV infection may affect the clinical course of IgA nephropathy, or exacerbate the disease.

Epstein-Barr virus-encoded latent membrane protein 1 induces epithelial to mesenchymal transition by inducing V-set Ig domain containing 4 (VSIG4) expression via NF-kB in renal tubular epithelial HK-2 cells

The epithelial to mesenchymal transition (EMT), a hallmark of chronic kidney disease, is a key event in the conversion from tubular epithelial cells to myofibroblasts in renal fibrosis. Epstein-Barr virus (EBV) is a γ-herpes oncovirus associated with chronic kidney disease. However, the relationship between EBV and the EMT process in renal tubular epithelial cells is not well understood. Among EBV-latent genes, EBV-encoded latent membrane protein 1 (LMP1) induces EMT by regulating a variety of molecules in EBV-induced oncogenic transformation. In this study, we investigated EBV-encoded LMP1 and EMT process markers in human proximal tubule epithelial cell line HK-2. LMP1 overexpression induces cell morphological changes via the epithelial to mesenchymal process in HK-2 cells, and these changes accelerate cell proliferation, cell motility, and invasion. Furthermore, VSIG4 upregulation by EBV-LMP1 induced LMP1-mediated EMT, cell motility, and invasion. VSIG4 upregulation by LMP1 was regulated at the transcriptional level via the NF-kB signaling axis. These results suggest that EBV-encoded LMP1 regulates EMT through the NF-kB-VSIG4 axis in HK-2 cells, and VSIG4 is a potential target in EBV-induced chronic kidney diseases.

Viruses and collapsing glomerulopathy: a brief critical review

BACKGROUND

Collapsing glomerulopathy may occur in an idiopathic (primary) form and in association with a wide spectrum of infectious and inflammatory conditions and medications. The association of collapsing glomerulopathy with human immunodeficiency virus (HIV)-1 infection is well established; less certain is the association with other viral infections.

METHODS

We searched PubMed for articles in all languages that addressed glomerulopathies associated with parvovirus B19, cytomegalovirus (CMV), Epstein-Barr virus (EBV), hepatitis C virus (HCV) and simian virus 40 (SV40).

RESULTS

Case reports and small-case series link infection with these common viruses and glomerular injury. The evidence for a pathogenic role is generally stronger for glomerulonephritis than for collapsing glomerulopathy.

CONCLUSIONS

The evidence linking collapsing glomerulopathy with CMV is relatively strong but not yet conclusive, while the evidence for a pathogenic role for EBV and parvovirus B19 is weaker.