Renal artery stenosis and focal segmental glomerulosclerosis in the contralateral kidney

A case report of successfully treated nephrotic syndrome after renal angioplasty

Background

The standard treatment of renovascular hypertension accompanying renal artery stenosis (RAS) consists of angioplasty and administration of antihypertensive medication. Although nephrotic syndrome (NS) has been reported to be associated with RAS, the development of NS after revascularization of RAS is extremely rare.

Case presentation

A 48-year-old man presented with uncontrolled hypertension and azotemia. The right kidney was atrophic, and RAS of the left kidney was suspected based on a post-captopril DTPA scan. His blood pressure stabilized after renal angioplasty; however, he complained of edema after 1 week. NS developed and was diagnosed as focal segmental glomerulosclerosis (FSGS) based on renal biopsy. He received an angiotensin receptor blocker. Proteinuria resolved after 1 year.

Conclusions

FSGS rarely develops after angioplasty of renal artery stenosis. This is the first report of successful treatment of this condition using an angiotensin receptor blocker during 1-year follow-up.

Takayasu arteritis with an initial presentation of chronic monoarthritis mimicking oligoarticular juvenile idiopathic arthritis

Patients with Takayasu arteritis (TA) generally present with non-specific symptoms that, if unrecognized and untreated, may develop vessel stenosis and/or aneurysm. There is limited data regarding chronic monoarthritis as the initial presentation in children with TA. We report a 6-yearold girl diagnosed and treated as oligoarticular juvenile idiopathic arthritis (JIA). She later developed stroke with malignant hypertension and was definitively diagnosed with TA. She additionally developed proteinuria secondary to focal segmental glomerulosclerosis. This is the report of a patient with chronic monoarthritis mimicking oligoarticular JIA which chronic monoarthritis was the presentation of TA. Since JIA is a diagnosis of exclusion, any atypical features of oligoarticular JIA should illuminate the possibility of an alternative diagnosis. Our literature review focused on musculoskeletal presentations of children with TA.

Complex glomerular pathology of thrombotic microangiopathy and focal segmental glomerulosclerosis forms tumor-like mass in a renal transplant donor with severe renovascular hypertension

The pathogenesis of glomerular hypertension-mediated FSGS and its histological variations in humans remains unknown. A 47-year-old man developed nephrotic syndrome, renal dysfunction, and malignant hypertension 2 years after donating a kidney to his son. The donor's remnant kidney developed renal mass at an upper pole which was fed by an aberrant artery that branched from the root of the renal artery. Furthermore, the main non-aberrant renal artery demonstrated severe stenosis that caused renovascular hypertension, resulting in malignant hypertension. Upon radiological examinations, a tumorous mass was detected. Because of progressive renal dysfunction, nephrectomy was performed. The kidney revealed a diffuse distribution of complex FSGS lesions, i.e., a random combination of cellular/collapsing FSGS and glomerular thrombotic microangiopathy, confined to the renal mass, whereas such lesions were absent in the non-mass portion. This indicated that severe glomerular hypertension alone caused FSGS with TMA features. Heterogeneous FSGS lesions let us surmise that glomerular hypertension promoted simultaneous damages in endothelial cells and podocytes, which synergistically progressed to glomerulosclerosis. This unique case uncovers causal relationships between unusual glomerular hypertension and severe forms of FSGS that was possibly caused by the disruption of homeostasis sustained by podocytes and endothelial cells.

A case of secondary focal segmental glomerulosclerosis associated with malignant hypertension

Focal segmental glomerulosclerosis (FSGS) is associated with various clinicopathological conditions, including hypertension. We report here a case of secondary FSGS associated with malignant hypertension. A 33-year-old man with a 1-month history of visual impairment and headache visited the Department of Ophthalmology at our hospital and was found to have hypertensive retinopathy and severe hypertension (230/160 mmHg). He was referred to our department based on suspected renal dysfunction. His blood pressure on admission was 250/130 mmHg. Physical examination and laboratory tests revealed hypertensive cardiac dysfunction, focal brain edema, renal dysfunction (serum creatinine, Cr 7.07 mg/dl, blood urea nitrogen, BUN 49.9 mg/dl), massive proteinuria (10.7 g/day), and thrombotic microangiopathy. Funduscopy showed exudate, hemorrhage, and papilledema. The cause of secondary hypertension could not be identified. He was treated for primary malignant hypertension, but required hemodialysis 3 days after admission due to anuria. Treatment with antihypertensive agents resulted in the gradual recovery of renal function, although heavy proteinuria continued with nephrotic syndrome. Renal biopsy performed 1 month after admission showed features of malignant nephrosclerosis with secondary FSGS. Hemodialysis was discontinued following further improvement in renal function and the most recent laboratory tests showed proteinuria 1.8 g/day and persistent renal dysfunction (BUN 36.5 mg/dl, Cr 3.14 mg/dl). Malignant hypertension may cause various injuries, including glomerular endothelial and epithelial cell injuries in glomerular hypertension and hyperfiltration, increase of the renin-angiotensin-aldosterone system, and endothelial-epithelial interaction, resulting in the development of secondary FSGS and heavy proteinuria.

Regional secondary focal segmental glomerulosclerosis in a transplanted kidney: resolution with treatment of a segmental renal artery stenosis

BACKGROUND

Conditions associated with high intraglomerular filtration pressure can cause secondary focal segmental glomerulosclerosis (FSGS). Unilateral renal artery stenosis (RAS) or its occlusion results in FSGS-like changes and the nephrotic syndrome in the contralateral kidney due to hyperfiltration. However, it has been rarely reported that stenosis of a renal arterial branch can result in FSGS-like changes in a different portion in the same kidney allograft.

CASE PRESENTATION

A 60-year-old male kidney recipient developed allograft dysfunction after angiotensin II receptor blockade for hypertension 4 months after transplantation. It was proven that one of two arterial branches of the graft was markedly stenotic. Graft dysfunction improved after percutaneous transluminal arterioplasty (PTA), however; the stenosis recurred and massive proteinuria developed 5 months later. Graft biopsy showed ischemic changes in the region fed by the stenotic artery branch and in contrast FSGS-like changes in the region fed by the other branch. His clinicopathological manifestation including massive proteinuria almost normalized after the repeat PTA.

CONCLUSION

Here we report a case of secondary FSGS of a kidney allograft due to severe RAS of a branch of the same kidney, in which clinical and pathological improvement were confirmed after radiological intervention. When moderate to severe proteinuria appear, secondarily developed FSGS as well as primary (recurrent or de novo) FSGS should be taken into account in kidney transplant recipients.

Renal manifestations in toddlers with Takayasu's arteritis and malignant hypertension

Three children under the age of 3 years presented with malignant hypertension, proteinuria, and acute kidney injury. Takayasu's arteritis was diagnosed on the basis of clinical symptoms of weight loss and low grade fever in conjunction with elevated sedimentation rate and radiographic evidence of aortic and renal artery stenosis. One patient had a renal biopsy which showed arteriolar sclerosis and focal glomerulosclerosis. All three patients required multiple antihypertensive agents, ultimately including angiotensin receptor blockers and/or angiotensin converting enzyme inhibitors. The vasculitis was treated with pulse corticosteroids followed by cyclophosphamide in one patient and mycophenolate mofetil as maintenance therapy in all. Follow-up has ranged from 2 to 8 years. Although global renal function has normalized in each patient, two have unilateral non-function of one kidney. The last patient has persistent aortic and renal artery stenosis with complex collateralization requiring ongoing medical and anticipated surgical management.

Renovascular hypertension: a unique cause of unilateral focal segmental glomerulosclerosis

A 48-year-old man presented with malignant hypertension and massive proteinuria. Renal angiography showed complete obstruction of the left renal artery and 99mTc-mercaptoacetylglycine (MAG3) renography showed a nonfunctioning left kidney. Percutaneous transluminal renal angioplasty of the left renal artery was unsuccessful; hence, the patient underwent left nephrectomy because of uncontrolled hypertension and proteinuria. Histological examination of a right kidney specimen revealed lesions of focal segmental glomerulosclerosis with benign nephrosclerosis. In contrast, histology of the left kidney showed typical ischemic kidney with hypertrophy of arteriolar smooth muscle cells. The patient responded favorably to the nephrectomy, as his blood pressure and urinary protein dramatically decreased with no antihypertensive medication. This case illustrates the heterogeneous effect of the renin-angiotensin system on either kidney in patients with renovascular hypertension due to unilateral renal artery stenosis.

A case of nephrotic syndrome associated with renovascular hypertension successfully treated with candesartan

A sixty eight-year-old man was referred to our hospital for evaluation of hypertension and hypokalemia. His chief complaints were fatigability and weakness of the lower extremities. Atrophy of the right kidney was noted on computed tomography. The laboratory findings demonstrated massive proteinuria, markedly elevated plasma renin activity, hypokalemia, and renal insufficiency. Angiography showed total occlusion of the right renal artery. The patient was diagnosed as having nephrotic syndrome associated with renovascular hypertension. Treatment with candesartan, an angiotensin-II-receptor blocker (ARB), controlled both hypertension and proteinuria satisfactorily without worsening of his renal function. This is the first report on the effect of ARB on nephrotic syndrome associated with renovascular hypertension. Based on the results, ARB can be considered a promising agent for the treatment of patients with renovascular hypertension with massive proteinuria and renal insufficiency.