Mini review: A unique case of crescentic C3 glomerulonephritis.

Kidney involvement is an under-recognized complication of non-Hodgkin lymphomas. They occur in a variety of mechanisms and differ widely in their clinical presentation. We take this opportunity to report a case of a 65 year-old man who developed a rapidly progressive glomerulonephritis within days after completing his first cycle of R-CHOP (Rituximab, Cyclophosphamide, Doxorubicin, Vincristine, Prednisolone) chemotherapy for newly diagnosed mantle cell lymphoma. He was odematous, hypertensive, oliguric with nephrotic range proteinuria and an active urine sediment. A renal biopsy showed a crescentic C3 glomerulonephritis (C3GN) with no evidence endocapillary or mesangial hypercellularity. He was promptly treated with immunosuppression and dialysis, with resumption of his chemotherapy. Genetic testing on complement proteins revealed a homozygous deletion spanning the CFHR1 and CFHR3 genes. Crescentic C3GN is a rare form of kidney injury, and this is the first known case of lymphoma-associated kidney involvement manifesting as C3GN. This article explores the possible mechanism of disease and reviews the literature of lymphoma-related kidney disease.

Clinical presentation, treatment and outcome of focal segmental glomerulosclerosis in Far North Queensland Australian adults.

AIM: The aim is to describe the clinical features, treatment and outcomes in Australian adults with focal segmental glomerulosclerosis and identify predictors of disease progression and all-cause mortality. METHODS: The study included all patients with biopsy confirmed focal segmental glomerulosclerosis between January 1997 and June 2014 at participating hospitals. Clinical factors, histopathological findings, biochemical markers and treatments were analysed and potential predictors of doubling serum creatinine, end stage kidney disease or death identified. RESULTS: A total of 98 patients were included with a median follow up of 4.3 years. Thirty-four (35%) patients were Aboriginal or Torres Strait Islander. Focal segmental glomerulosclerosis not-otherwise-specified was the most common variant. Seventeen (59%) patients initially treated with immunosuppression experienced an improvement in renal function. At the end of follow up, 43 (44%) patients had progressed to the composite outcome. Baseline tubulointerstitial scarring and lower haemoglobin predicted shorter time to doubling serum creatinine. Dual diagnosis, higher serum creatinine, lower estimated glomerular filtration rate and doubling creatinine were associated with shorter time to end stage kidney disease with remission the only protective factor. Age was the only variable associated with all-cause mortality. CONCLUSION: Focal segmental glomerulosclerosis holds serious implications for patients. Concomitant diabetic nephropathy, higher serum creatinine and lower estimated glomerular filtration rate at renal biopsy were associated with poorer renal prognosis. Indigenous people had a female predominance and are over-represented in relation to their population size, however, were not associated with poorer prognosis. Remission was the only modifiable variable and thus should be at the forefront of patient management goals and future studies.

Decreased apoptosis repressor with caspase recruitment domain confers resistance to sunitinib in renal cell carcinoma through alternate angiogenesis pathways.

Apoptosis repressor with caspase recruitment domain (ARC), an endogenous inhibitor of apoptosis, is upregulated in a number of human cancers, thereby conferring drug resistance and giving a rationale for the inhibition of ARC to overcome drug resistance. Our hypothesis was that ARC would be similarly upregulated and targetable for therapy in renal cell carcinoma (RCC). Expression of ARC was assessed in 85 human RCC samples and paired non-neoplastic kidney by qPCR and immunohistochemistry, as well as in four RCC cell lines by qPCR, Western immunoblot and confocal microscopy. Contrary to expectations, ARC was significantly decreased in the majority of clear cell RCC and in three (ACHN, Caki-1 and 786-0) of the four RCC cell lines compared with the HK-2 non-cancerous human proximal tubular epithelial cell line. Inhibition of ARC with shRNA in the RCC cell line (SN12K1) that had shown increased ARC expression conferred resistance to Sunitinib, and upregulated interleukin-6 (IL-6) and vascular endothelial growth factor (VEGF). We therefore propose that decreased ARC, particularly in clear cell RCC, confers resistance to targeted therapy through restoration of tyrosine kinase-independent alternate angiogenesis pathways. Although the results are contrary to expectations from other cancer studies, they were confirmed here with multiple analytical methods. We believe the highly heterogeneous nature of cancers like RCC predicate that expression patterns of molecules must be interpreted in relation to respective matched non-neoplastic regions. In the current study, this procedure indicated that ARC is decreased in RCC.

Atypical HUS associated with severe, unexpected antibody-mediated rejection post kidney transplant.

We present a case of an unsensitized patient with end-stage kidney disease secondary to atypical haemolytic uremic syndrome (aHUS) with mutations in CD46/MCP and CFH who developed severe, intractable antibody-mediated rejection (ABMR) unresponsive to therapy post kidney transplantation. There were no haematological features of thrombotic microangiopathy. The patient received standard induction therapy and after an initial fall in serum creatinine, severe ABMR developed in the setting of urosepsis. Despite maximal therapy with thymoglobulin, plasma exchange and methylprednisolone, rapid graft loss resulted and transplant nephrectomy was performed. Luminex at 4 weeks showed a new DSA and when repeated after nephrectomy showed antibodies to each of the 5 mismatched antigens with high MFI. The rate of recurrence of disease in patients with aHUS referred for transplantation is 50% and is associated with a high rate of graft loss. It is dependent in part on the nature of the mutation with circulating factors CFH and CFI more likely to cause recurrent disease than MCP which is highly expressed in the kidney. There is increasing interest in the role of complement in the development and propagation of ABMR via terminal complement activation. This case suggesting that dysregulation of the alternative complement pathway within the transplant kidney may have contributed to the severe AMR. Very little is known about the impact of complement dysregulation and the development of anti HLA antibodies however the strength of HLA antibody formation was prominent in this case.

Chronic kidney cortical damage is associated with baseline kidney function and albuminuria in patients managed with radical nephrectomy for kidney tumours.

This study evaluated the relationship between histological markers of chronic kidney damage in patients undergoing radical nephrectomy for kidney tumours and preoperative kidney function, degree of albuminuria, and changes in glomerular volume. A schema to grade chronic kidney damage could be used to identify patients at risk of developing CKD following nephrectomy. Non-neoplastic cortical tissue was sourced from 150 patients undergoing radical nephrectomy for suspected kidney cancer. This tissue was evaluated for indicators of chronic damage, specifically: glomerulosclerosis, arteriosclerosis, interstitial fibrosis, and tubular atrophy. Glomerular volume was determined using the Weibel and Gomez method. Associations between these parameters and both estimated glomerular filtration rate (eGFR) and albumin-creatinine ratio (ACR) were determined using either a Mann-Whitney U-test or a Kruskal-Wallis ANOVA. Associations between both eGFR and ACR and glomerular volume were assessed using linear regression. eGFR was inversely associated with the degree of glomerulosclerosis (p < 0.001), vascular narrowing (p = 0.002), tubular atrophy (p < 0.001), and interstitial fibrosis (p < 0.001). ACR was associated only with the degree of interstitial fibrosis (p = 0.02) and tubular atrophy (p = 0.02). Glomerular volume was greater for males, diabetics, hypertensive patients, and patients with a greater degree of interstitial fibrosis. Glomerular volume was positively associated with ACR. A schema to grade chronic damage was developed. The proposed schema is associated with baseline clinical indices of kidney function and damage. Longitudinal validation is necessary to determine the prognostic utility of this schema.

An association between membranoproliferative glomerulonephritis and metastatic colorectal carcinoma: a case report.

BACKGROUND: Membranoproliferative glomerulonephritis is a common pattern of glomerular injury in monoclonal gammopathy, but has only rarely been associated with solid organ tumors, mainly lung, renal, gastric, breast, and prostate. There have been two reported cases of membranoproliferative glomerulonephritis associated with adenocarcinoma of the colon and rectum, although the association may be coincidental. We report a case where nephrotic syndrome due to membranoproliferative glomerulonephritis developed in a patient with colorectal carcinoma and elucidate some of the pathophysiological mechanisms underpinning this presentation. CASE PRESENTATION: A 54-year-old white man with a history of adenocarcinoma of the colon with metastasis to the liver and ureter presented with a 1-week history of bilateral pedal edema, and worsening hypertension and renal function. A renal biopsy confirmed membranoproliferative glomerulonephritis type I. Curative therapy for the malignancy was not possible, so treatment was commenced with prednisolone with consequential biochemical improvement in renal function and proteinuria, although his serum albumin remained low. CONCLUSIONS: This case report illustrates an association between membranoproliferative glomerulonephritis and metastatic colorectal carcinoma and adds to the evidence to consider malignancy to be an underlying pathology among newly diagnosed cases of nephrotic syndrome. In the clinical setting, treatment of the underlying malignancy should be first considered in patients with a tumor presenting with kidney disease which is suspected to be paraneoplastic in etiology.

Expression of Bcl-xL and Mcl-1 in the nonmelanoma skin cancers of renal transplant recipients.

OBJECTIVES: This study aims to investigate how immunosuppression influences the protein expression of antiapoptotic members of the Bcl-2 family-namely, Bcl-xL and Mcl-1-in nonmelanoma skin cancer (NMSC) and the peritumoral epidermis of renal transplant recipients. METHODS: NMSC and peritumoral epidermis protein expression of Bcl-xL and Mcl-1 were assessed by immunohistochemistry in renal transplant recipients receiving tacrolimus or sirolimus and the general population not receiving immunosuppression. RESULTS: NMSC from renal transplant recipients compared with patients not receiving immunosuppressant medications had a reduced Bcl-xL expression intensity (P = .042). Mcl-1 expression intensity in NMSC was decreased in tacrolimus-treated patients compared with sirolimus-treated patients and the nonimmunosuppressed population (P = .024). Bcl-xL expression intensity was increased in peritumoral epidermis compared with NMSC (P = .002). CONCLUSIONS: It was shown for the first time that Bcl-xL and Mcl-1 expression are widespread in the peritumoral epidermis and NMSC of renal transplant recipients. Importantly in NMSC, Bcl-xL expression was reduced with immunosuppression exposure, and Mcl-1 expression was reduced in tacrolimus-treated compared with sirolimus-treated patients.

Hydralazine-induced anti-neutrophil cytoplasmic antibody-positive renal vasculitis presenting with a vasculitic syndrome, acute nephritis and a puzzling skin rash: a case report.

INTRODUCTION: Anti-neutrophil cytoplasmic antibody-associated vasculitis has been associated with many drugs and it is a relatively rare side effect of the antihypertensive drug hydralazine. The diagnosis and management of patients who have anti-neutrophil cytoplasmic antibody-associated vasculitis may be challenging because of its relative infrequency, variability of clinical expression and changing nomenclature. The spectrum of anti-neutrophil cytoplasmic antibody-associated vasculitis is wide and can be fatal. This case documents a 62-year-old woman who presented with hydralazine-induced anti-neutrophil cytoplasmic antibody-positive renal vasculitis with a puzzling cutaneous rash. CASE PRESENTATION: We report a rare case of hydralazine-induced anti-neutrophil cytoplasmic antibody-associated vasculitis in a 62-year-old Caucasian woman who presented with a vasculitic syndrome with a sore throat, mouth ulcers and otalgia after several months of constitutional symptoms. She then proceeded to develop a rash over her right lower limb. Clinically, the rash had features to suggest Sweet's syndrome, but also had some appearances consistent with embolic phenomena and did not have the appearance of palpable purpure usually associated with cutaneous vasculitis. Differential diagnoses were hydralazine-associated Sweet's syndrome, streptococcal-induced cutaneous eruption or an unrelated contact dermatitis. A midstream urine sample detected glomerular blood cells in the setting of anti-neutrophil cytoplasmic antibody-positive renal vasculitis and Streptococcus pyogenes bacteremia. A renal biopsy revealed a pauci-immune, focally necrotizing glomerulonephritis with small crescents. Her skin biopsy revealed a heavy neutrophil infiltrate involving the full thickness of the dermis with no evidence of a leucocytoclastic vasculitis, but was non-specific. She was initially commenced on intravenous lincomycin for her bloodstream infection and subsequently commenced on immunosuppression after cessation of hydralazine. The patient was subsequently discharged from hospital after a rapid clinical improvement. CONCLUSION: Hydralazine-induced anti-neutrophil cytoplasmic antibody-positive renal vasculitis is a rare adverse effect and can present with a severe vasculitic syndrome with multiple organ involvement. Features of this association include the presence of high titres of anti-myeloperoxidase-anti-neutrophil cytoplasmic antibody with multi-antigenicity, positive anti-histone antibodies and the lack of immunoglobulin and complement deposition histopathogically. A rash that is characteristic of Sweet's syndrome has also been described as an association. Prompt cessation of hydralazine may be sufficient to reverse disease activity but immunosuppression may be needed for definite treatment.