1/23. A regulatory region rearranged bk virus is associated with tubulointerstitial nephritis in a rejected renal allograft.A renal allograft transplant patient with high serum creatinine presented clinical symptoms of rejection. Sections of renal biopsy tissue showed mononuclear leukocyte infiltration in the tubulointerstitium and nuclear enlargement with inclusions in the tubular epithelium. The morphological characteristics resembled polyomavirus-induced interstitial nephritis. Electron microscopy of the nuclear inclusions showed paracrystalline arrays of naked viral particles with a diameter of 45 nm. Molecular studies revealed that a new variant of bk virus (BKV) with rearrangement at the regulatory region was involved in the nephritis. The BKV regulatory region contained a tandem repeat from the P-block to the Q-block causing duplication of several important transcriptional elements or transcriptional factor binding motifs. This is the first report to show a naturally occurring BKV variant with regulatory region rearrangement associated with tubulointerstitial nephritis.- - - - - - - - - - ranking = 1keywords = tubulointerstitial, tubulointerstitial nephritis, nephritis, interstitial nephritis, interstitial (Clic here for more details about this article) |
2/23. Molecular characterization and sequence analysis of polyomavirus BKV-strain in a renal-allograft recipient.The significance of polyomavirus (PV) infection was investigated in a 53-year-old patient who underwent renal transplantation and was treated with triple immunosuppressive therapy (tacrolimus, prednisone, and azathioprine). A renal biopsy taken because of the suspicion of acute rejection showed focal inflammatory interstitial infiltration, tubulitis, and tubular cell nuclear changes consistent with the hypothesis of viral infection. Both the tubular and decoy cells identified by means of urinalysis positively stained for anti-SV40 antibody. polymerase chain reaction performed on the dna extracted from renal tissue and isolated from urine showed the presence of an antigenic variant (AS) of the BKV archetype after sequence analysis of the transcription control region (TCR). On the basis of the diagnosis of BKV infection, immunosuppressive therapy was reduced. The patient's renal function improved and was still stable 8 months later when urinalysis showed only a few decoy cells, which were found to be infected by JC but not bk virus. These data suggest that only the BKV, probably favoured by immunosuppressive therapy (tacrolimus), causes renal damage. It is worth underlining that even small and sporadic viral genome mutations may lead to pathologic effects.- - - - - - - - - - ranking = 0.00082484217359909keywords = interstitial (Clic here for more details about this article) |
3/23. polyomavirus BK nephropathy in a kidney transplant recipient: critical issues of diagnosis and management.diagnosis of polyomavirus BK nephropathy and treatment by low-dose immunosuppression may be optimized by using surrogate markers, such as the detection of viral inclusion bearing cells in the urine and polyomavirus BK dna in plasma by polymerase chain reaction. These markers were used prospectively in the management of a 44-year-old woman and led to the diagnosis of polyomavirus BK nephropathy at an early stage. The management was complicated by the concurrence of acute allograft rejection. Two treatment steps were initiated: antirejection therapy consisting of methylprednisolone for 3 days followed by lowering of the maintenance immunosuppression. This treatment resulted in a return of the serum creatinine concentration to the baseline of 1.6 mg/L, clearance of polyomavirus BK from plasma, and disappearance of viral inclusion bearing cells from the urine. After 2 months of stable allograft function, a control biopsy confirmed the resolution of polyomavirus BK nephropathy. Histologic signs of acute interstitial rejection were found and preemptively treated by methylprednisolone without altering the baseline regimen. Allograft function remained stable without evidence of recurrent polyomavirus BK nephropathy. This case shows the value of surrogate markers used in a prospective fashion for diagnosis and management of polyomavirus BK nephropathy with concurrent rejection.- - - - - - - - - - ranking = 0.00082484217359909keywords = interstitial (Clic here for more details about this article) |
4/23. Successful retransplantation after renal allograft loss to polyoma virus interstitial nephritis.BACKGROUND: Although polyoma virus infection is being increasingly recognized as a cause of renal allograft dysfunction and failure, the risk of polyoma recurrence in a subsequent transplant is unknown. We present the first reported case of successful retransplantation after polyoma virus-induced renal allograft loss. CASE REPORT: A 40-year-old Caucasian woman received a cadaveric kidney transplant. Baseline immunosuppression included corticosteroids, mycophenolate mofetil, and tacrolimus. Her post-transplant clinical course was complicated by an early acute rejection episode on posttransplant day (PTD) 6, that warranted treatment with OKT3. A biopsy performed on PTD 154 to evaluate a rise in creatinine revealed polyoma virus interstitial nephritis. Despite reduction in immunosuppression, the renal function progressively worsened and dialysis was initiated by PTD 160, followed by transplant nephrectomy on PTD 184. Four months later, she received a living related kidney from her sister. immunosuppression was initiated with prednisone, azathioprine, and tacrolimus. She had immediate graft function with a decrease in serum creatinine from 12.8 to 1.1 mg/dl. Three and one-half years after her second renal transplant, her allograft functions well, with a serum creatinine of 1 mg/dl. Both quantitative and qualitative assays of blood and urine (by PCR) remain negative for bk virus, indicating the absence of virus reactivation. CONCLUSION: Judicious retransplantation should be considered as a therapeutic option in the management of polyoma virus induced graft failure. Previous graft loss secondary to polyoma virus infection is not a contraindication to retransplantation.- - - - - - - - - - ranking = 0.2385979176603keywords = nephritis, interstitial nephritis, interstitial (Clic here for more details about this article) |
5/23. bk virus regulatory region rearrangements in brain and cerebrospinal fluid from a leukemia patient with tubulointerstitial nephritis and meningoencephalitis.bk virus (BKV) was recovered by polymerase chain reaction (PCR) from brain, kidney, lung, urine, and cerebrospinal fluid (CSF) of a fatal case of BKV tubulointerstitial nephritis with dissemination to lung and brain. Viral regulatory regions in PCR-amplified urine and the lung samples were identical to the archetypal structure, WWT. In the brain and CSF, a rearranged sequence predominated, however. A 94-bp deletion preceded a 71-bp tandem duplication because the same 94-bp segment was deleted from both copies. PCR-amplified regulatory region products were cloned and sequenced to define further the extent of the rearranged structures. Two kidney clones were archetypal, whereas two others were rearranged differently from the brain and from each other. In contrast to the brain clones, the kidney rearrangements seemed to involve deletion after duplication. Three of four brain clones sequenced were identical to the rearrangement found to dominate in the PCR product. A fourth clone showed two short deletions without any duplication. The four CSF clones all showed rearrangements identical to that which was amplified by PCR from CSF and brain. This represents the first molecular analysis of a BKV strain obtained from a central nervous system infection, and it reveals regulatory region rearrangements reminiscent of those described in jc virus from brains with progressive multifocal leukoencephalopathy. We suggest that the presence in the CSF of BKV with a dominant rearranged regulatory region may be useful in the diagnosis of BKV meningoencephalitis secondary to BKV nephritis.- - - - - - - - - - ranking = 0.95228041646794keywords = tubulointerstitial, tubulointerstitial nephritis, nephritis, interstitial nephritis, interstitial (Clic here for more details about this article) |
6/23. BK polyomavirus interstitial nephritis in a renal transplant patient with no previous acute rejection episodes.A renal transplant patient treated with tacrolimus and mycophenolate-mofetil (MMF) developed progressive graft function deterioration 10 months after transplantation. biopsy of the graft showed severe, focally accentuated interstitial inflammation with focal tubulitis and tubular necrosis, and medium-severe interstitial fibrosis with focal tubular atrophy. Glomerular and vascular structures were preserved. On careful examination, in some sections, tubular epithelial cells showed a definite increase with deformation of the nuclear shape, chromatin irregularities with peripheral dislocation and inclusion bodies. These cytopathic changes suggested polyoma virus infection ("decoy cells"). Subsequent screening of the urinary sediment confirmed the presence of many "decoy cells". Immunohistochemical analysis of the biopsy showed many tubular cells were strongly positive for the SV 40 antigen, specific for BK polyoma virus. A diagnosis of interstitial nephritis due to BK polyoma virus was made, though the coexistence of cellular rejection could not be excluded. At variance with previous reports, our patient had not had repeated episodes of rejection before biopsy or heavy immunosuppressive treatment, such as ALG, OKT3, after transplantation. This case shows that even in the absence of vigorous anti-rejection therapy an immunosuppressive regimen based on tacrolimus and MMF may involve the risk of BK polyoma virus- associated interstitial nephritis.- - - - - - - - - - ranking = 0.28796718553956keywords = nephritis, interstitial nephritis, interstitial (Clic here for more details about this article) |
7/23. Bladder carcinoma in a transplant recipient: evidence to implicate the BK human polyomavirus as a causal transforming agent.The BK polyomavirus (BKV) infects most of the human population, but clinically relevant infections are mostly limited to individuals who are immunosuppressed. In transplant recipients, BKV has been associated with ureteral stenosis, interstitial nephritis, and hemorrhagic cystitis. The role of BKV in the development of human tumors is intriguing but uncertain. BKV has been identified in various tumor types including urothelial carcinoma, but the ubiquitous presence of BKV as a latent infection has confounded efforts to validate any causal role in cancer development. We report the case of a simultaneous pancreas and kidney transplant recipient who developed BKV interstitial nephritis and carcinoma of the bladder with widespread metastases. High level expression of BKV large T antigen in the primary and metastatic carcinoma, but not in the nonneoplastic urothelium, implicates BKV as an etiologic agent in the development of this tumor.- - - - - - - - - - ranking = 0.09543916706412keywords = nephritis, interstitial nephritis, interstitial (Clic here for more details about this article) |
8/23. De novo C1q nephropathy in the renal allograft of a kidney pancreas transplant recipient: bk virus-induced nephropathy?C1q nephropathy is a distinct entity characterized by extensive and dominant C1q mesangial deposition with associated steroid resistant proteinuria in the absence of systemic lupus erythematosus. Several morphological patterns ranging from very subtle glomerular alterations to focal/segmental glomerulosclerosis and mesangial proliferative changes have been described. Interstitial nephritis secondary to BK polyomavirus is a recently recognized complication in kidney transplant recipients. It may be associated with a tubulitis-like picture, mimicking sometimes acute tubular rejection. We report the case of a kidney pancreas transplant recipient who developed de novo C1q nephropathy, in the setting of BK polyomaviral interstitial nephritis. He presented with renal allograft dysfunction and a kidney biopsy was performed. It was interpreted as acute cellular rejection. C1q deposits were detected by immunofluorescence studies and electron microscopy. The patient did not respond clinically to appropriate anti-rejection treatment and a second renal biopsy was performed. The possibility of an interstitial nephritis secondary to BK polyomavirus mimicking rejection was suggested. Special immunohistochemical and blood/urine PCR studies for bk virus were performed, confirming the diagnosis of bk virus tubulonterstitial nephritis with a persistent, probable bk virus induced C1q nephropathy.- - - - - - - - - - ranking = 0.15363504203605keywords = nephritis, interstitial nephritis, interstitial (Clic here for more details about this article) |
9/23. BK polyomavirus interstitial nephritis in a renal allograft recipient.Human polyomavirus (PV) interstitial nephritis has recently been recognized as a cause of severe renal allograft dysfunction. It occurs in immunosuppressed patients after reactivation of the latent virus PV type BK (bk virus) in the renal epithelium. BK disease is defined as a morphologically manifest renal infection with cytopathic signs accompanied by varying degrees of interstitial inflammatory cell infiltrates and functional impairment. It is also identified by the presence of cells containing viral inclusion bodies (decoy cells) in the urine. The authors report a case of BK PV interstitial nephritis in a 36-year-old renal allograft recipient. Under light microscopy the chief diagnostic indicator was detection of intranuclear viral inclusions, which were found exclusively in tubular epithelial cells. Cells with viral changes were often enlarged with nuclear atypia and chromatin basophilia. Widespread interstitial plasma cell infiltrates associated with tubulitis were present. Intranuclear paracrystalline arrays of virus particles 35-38 nm in diameter were present as characteristic ultrastructural indicators. urine samples revealed decoy cells with ground-glass-type intranuclear inclusions positive for bk virus by electron microscopy.- - - - - - - - - - ranking = 0.28796718553956keywords = nephritis, interstitial nephritis, interstitial (Clic here for more details about this article) |
10/23. Renal allograft loss as the result of polyomavirus interstitial nephritis after simultaneous kidney-pancreas transplantation: results with kidney retransplantation.BACKGROUND: polyomavirus (PV) infection in kidney transplant patients has been reported to cause interstitial nephritis and subsequent graft loss. The cornerstone of current therapy is a reduction in immunosuppression, which can subsequently lead to kidney allograft rejection. This dilemma becomes even more challenging in the setting of simultaneous kidney-pancreas transplantation, because a reduction in immunosuppression may result in rejection of the pancreas allograft. Antiviral therapy has not been shown to be clinically successful in decreasing the risk of graft loss secondary to PV infection. Furthermore, because of limited experience, the decision to perform retransplantation in patients who lost their primary kidney grafts to PV interstitial nephritis becomes a difficult one. methods: Retrospective review and case studies. RESULTS: We report two successful living donor kidney retransplants in simultaneous kidney-pancreas transplant patients who lost their first kidney grafts to PV infection. Both patients are receiving rimantadine therapy and performing well, with functioning kidney and pancreas grafts and no evidence of recurrent PV interstitial nephritis 22 and 37 months after retransplantation. CONCLUSIONS: Although follow-up is limited, our initial experience would indicate that graft loss secondary to PV interstitial nephritis is not an absolute contraindication for kidney retransplantation.- - - - - - - - - - ranking = 0.38175666825648keywords = nephritis, interstitial nephritis, interstitial (Clic here for more details about this article) |
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