Minimal change disease in a patient receiving IFN-alpha therapy for chronic hepatitis C virus infection

Kidney and urinary tract involvement in systemic mastocytosis

Systemic mastocytosis (SM) is a disorder of excessive mast cell accumulation in tissues due to a somatic gain-of-function mutation, commonly in the KIT gene, which prevents apoptosis of mast cells. Whereas bone marrow, skin, lymph nodes, spleen and gastrointestinal tract are commonly involved, kidneys are rarely involved directly by SM. However, there are increasing reports of indirect kidney involvement in patients with SM. Novel anti-neoplastic agents to treat advanced forms of SM include non-specific tyrosine kinase inhibitors, which are reported to be associated with kidney dysfunction in some patients. SM is also associated with immune-mediated glomerulonephritis (GN) such as mesangioproliferative GN, membranous nephropathy and diffuse proliferative GN. Kidney injury, in the form of monoclonal deposition disease and primary light chain amyloidosis, is reported in SM associated with plasma cell dyscrasia. In this narrative review we discuss the various ways kidneys (and the urinary tract) are involved in patients with SM.

Broad spectrum of interferon-related nephropathies-glomerulonephritis, systemic lupus erythematosus-like syndrome and thrombotic microangiopathy: A case report and review of literature

BACKGROUND

Interferons (IFNs) are characterized by a wide range of biological effects, which justifies their potential therapeutic use in several pathologies, but also elicit a wide array of adverse effects in almost every organ system. Among them, renal involvement is probably one of the most complex to identify.

CASE SUMMARY

We describe four cases of kidney damage caused by different IFN formulations: IFN-β-related thrombotic microangiopathy, IFN-β-induced systemic lupus erythematosus, and two cases of membranous nephropathy secondary to pegylated-IFN-α 2B. In each case, we carefully excluded any other possible cause of renal involvement. Once suspected as the casual relationship between drug and kidney damage, IFN treatment was immediately discontinued. In three cases, we observed a complete and persistent remission of clinical and laboratory abnormalities after IFN withdrawal, while the patient who developed thrombotic microangiopathy, despite IFN withdrawal and complement-inhibitor therapy with eculizumab, showed persistent severe renal failure requiring dialysis.

CONCLUSION

This case series highlights the causal relationship between IFN treatment and different types of renal involvement and enables us to delineate several peculiarities of this association.

Acute tubular necrosis following interferon-based therapy for hepatitis C: case study with literature review

BACKGROUND/AIMS

Interferon treatment of malignant or viral diseases can be accompanied by various side-effects including nephro-toxicity.

METHODS

We report on a 68-year-old Caucasian male who received dual therapy with pegylated interferon 2a plus ribavirin for chronic hepatitis C.

RESULTS

After three months of antiviral therapy, the patient developed acute kidney failure (serum creatinine up to 6 mg/dL) with mild proteinuria (500 mg daily) and haematuria. Immediate immunosuppressive therapy with high-dose intravenous steroids did not improve kidney function. Kidney biopsy was consistent with acute tubular necrosis without glomerular abnormalities. He started long-term peritoneal dialysis (four regular exchanges) to provide both dialysis adequacy and ascites removal. Kidney function gradually improved over the following months (serum creatinine around 2 mg/dL) and peritoneal dialysis was continued with two exchanges daily. The temporal relationship between the administration of the drug and the occurrence of nephro-toxicity, and the absence of other obvious reasons for acute tubular necrosis support a causative role for pegylated interferon; benefit on kidney disease was noted after withdrawal of antiviral agents. An extensive review of the literature on acute tubular necrosis associated with interferon-based therapy, based on in vitro data and earlier case-reports, has been made. The proposed pathogenic mechanisms are reviewed.

CONCLUSIONS

Our case emphasizes the importance of monitoring renal function during treatment of chronic hepatitis C with antiviral combination therapy as treatment may precipitate kidney damage at tubular level.

An unexpected presentation: minimal change disease in an adult with treatment-naïve hepatitis C

Minimal change disease is the most common glomerular disease affecting children; its prevalence among adults, however, is eclipsed by other glomerular pathologies. Each of these diseases has a number of classic associations, such as membranoproliferative glomerulonephritis with hepatitis C. We report the case of a middle-aged African-American male who presented with the nephrotic syndrome and acute renal failure and was concomitantly diagnosed with a new hepatitis C infection. He also had a history of urethral strictures with potential reflux nephropathy, which--in combination with his African-American race--also made focal segmental glomerulosclerosis a diagnostic possibility. Full laboratory evaluation did not distinguish the cause of his massive proteinuria; subsequent renal biopsy ultimately revealed minimal change disease. A full course of high-dose steroids eventually reduced his proteinuria, after which his renal failure resolved as well without need for hemodialysis.

Treatment with IFN-{alpha}, -{beta}, or -{gamma} is associated with collapsing focal segmental glomerulosclerosis

BACKGROUND AND OBJECTIVES

Treatment with IFN is rarely associated with nephrotic syndrome and renal biopsy findings of minimal-change disease or FSGS.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We report 11 cases of collapsing FSGS that developed during treatment with IFN and improved after discontinuation of therapy.

RESULTS

The cohort consists of seven women and four men with a mean age of 48.2 yr. Ten of the 11 patients were black. Six patients were receiving IFN-alpha for hepatitis C virus infection (n = 5) or malignant melanoma (n = 1), three were receiving IFN-beta for multiple sclerosis, and two were treated with IFN-gamma for idiopathic pulmonary fibrosis. After a median and mean [corrected] duration of therapy of 4.0 and 12.6 months, respectively, patients presented with acute renal failure (mean creatinine 3.5 mg/dl) and nephrotic-range proteinuria (mean 24-hour urine protein 9.7 g). Renal biopsy revealed collapsing FSGS with extensive foot process effacement and many endothelial tubuloreticular inclusions. Follow-up was available for 10 patients, all of whom discontinued IFN. At a mean of 23.6 months, nine of 10 patients had improvement in renal function, including one with complete remission and two with partial remission. Among the seven patients with available data, mean proteinuria declined from 9.9 to 3.0 g/d. Four of the seven patients were treated with immunosuppression, and there was no detectable benefit.

CONCLUSIONS

Collapsing FSGS may occur after treatment with IFN-alpha, -beta, or -gamma and is typically accompanied by the ultrastructural finding of endothelial tubuloreticular inclusions. Optimal therapy includes discontinuation of IFN.

Drug-induced Kidney Disease – Pathology and Current Concepts

The kidneys can be damaged by a large number of therapeutic agents. The aim of this article is to discuss the pathological features of drug-induced renal disease as diagnosed by kidney biopsy. The literature is reviewed and cases seen by the authors that have a known drug association are analysed. Mechanisms of injury are varied and all renal structures may be affected. The tubulointerstitial compartment is most frequently involved, but glomerular and vascular lesions are seen in a significant proportion of cases. Key words: Drug, Kidney, Nephrotoxicity, Pathology

Up-regulation of TRAIL mRNA expression in peripheral blood mononuclear cells from patients with minimal-change nephrotic syndrome

BACKGROUND

Minimal-change nephrotic syndrome (MCNS) is considered to be associated with T-cell dysfunction and with the abnormal secretion of putative glomerular permeability factors; however, the nature of such factors remains elusive.

METHODS

To identify up-regulated genes during the nephrosis phase, we undertook serial analyses of gene expression (SAGE) in peripheral blood mononuclear cells (PBMC) from a patient with MCNS sampled during the nephrosis and remission phases. To confirm the SAGE results, we performed quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR) analyses. We also measured the serum levels of the identified gene product in nephrosis and remission samples from 29 MCNS patients, 57 patients with nephrotic syndrome due to other types of glomerular diseases and 30 healthy individuals.

RESULTS

Using more than 20,000 SAGE tags, we identified 15 functionally known genes that were up-regulated (>or=4-fold) in PBMC from the MCNS patient during the nephrosis phase. For further examination, we selected two genes encoding secretory proteins, namely tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) and tissue inhibitor of metalloprotease 1. Real-time RT-PCR analysis confirmed a higher expression of TRAIL mRNA in PBMC during nephrosis than during remission in eight MCNS patients. The expression pattern of TRAIL mRNA, however, was variable among four patients with membranous nephropathy. There was no significant increase of serum levels of a soluble form of TRAIL in MCNS patients during the nephrosis phase.

CONCLUSIONS

These results suggest that the intracellular TRAIL mRNA expression in PBMC is up-regulated in MCNS patients during the nephrosis phase. This change may represent either an epiphenomenon or it may provide a potential explanation for the altered T-cell function in MCNS.