Nodular mesangial glomerulosclerosis in patients without manifest diabetes mellitus

Idiopathic nodular glomerulosclerosis in Chinese patients: a clinicopathologic study of 20 cases

BACKGROUND

The objective of this study is to investigate the frequency and clinicopathological features of idiopathic nodular glomerulosclerosis (ING) in Chinese patients, on which there has been no previously published information.

METHODS

Native kidney biopsies performed at a kidney histopathological center in Shanghai between January 1, 2009 and December 31, 2011 were retrospectively examined and relevant clinical data were reviewed.

RESULTS

All kidney biopsy specimens (3,480) were examined. After excluding specimens from patients with diabetes, fasting hyperglycemia or hemoglobin A1c elevation and other known entities associated with nodular glomerulosclerosis, 20 ING cases (1 in 174 biopsies) were identified. Patients with ING had a median age of 55.5 years, 16 (80 %) were male, 19 (95 %) had a body mass index (BMI) ≥25 kg/m(2) [BMI ≥30 in 8 (40 %)], 18 (90 %) were hypertensive, 17 (85 %) had a history of cigarette smoking (mean pack-years 19.8 ± 2.4), and 10 (50 %) had hyperlipidemia. All 20 patients had >1 g/day proteinuria with a mean of 2.85 ± 0.33 g/day (seven had nephrotic-range proteinuria). Mean serum creatinine at the time of kidney biopsy was 4.23 ± 0.53 mg/dL (338.2 ± 44.7 μmol/L). Histopathologically, all specimens showed varying degrees of nodular glomerulosclerosis, glomerular basement membrane thickening, foot process effacement, interstitial fibrosis and arterial hyalinosis/sclerosis. Immunofluorescence was non-specific. At follow-up of 22.1 ± 1.15 days post-biopsy, six patients had developed end-stage renal failure and five had worsening serum creatinine concentrations not requiring dialysis.

CONCLUSION

ING is rare and appears to be associated with overweight, hypertension and cigarette smoking in Chinese patients.

A case of idiopathic nodular glomerulosclerosis with fibrin caps

We report a case of idiopathic nodular glomerulosclerosis (ING) mimicking diabetic Kimmelstiel-Wilson glomerulopathy. A 72-year-old man suffering from nephritic syndrome and renal dysfunction had no prior history of diabetes mellitus, but had impaired glucose tolerance and a history of hypertension and smoking. A kidney biopsy showed increased mesangial matrix with Kimmelstiel-Wilson-like nodules, glomerular basement membrane thickening and capillary microaneurysms. Additionally, a large amount of fibrin caps detectable as electron-dense subendothelial material by electron microscopy were observed. Although ING with fibrin caps has been rarely reported, the large number of fibrin caps seen in this case may be due to the advanced clinical stage.

Idiopathic nodular glomerulosclerosis: a clinicopathologic study of 15 cases

Idiopathic nodular glomerulosclerosis is an enigmatic condition closely resembling diabetic nodular glomerulosclerosis without evidence of diabetic mellitus or other specific disease. Idiopathic nodular glomerulosclerosis remains a rare disease entity with an unclear pathogenesis. Clinicopathologic features of 15 patients with idiopathic nodular glomerulosclerosis were evaluated in a retrospective review of renal biopsies between 1998 and 2007. Our study cohort consisted predominantly of older (mean age, 64.2 years) white (73%) women (67%). Fourteen patients (93%) had a history of hypertension, and 10 (67%) were active smokers at the time of biopsy. Nine patients (60%) were obese (body mass index, >30 kg/m(2)) and 4 (27%) were overweight (body mass index, 25-29.9 kg/m(2)). Fourteen patients (93%) presented with renal insufficiency with mean serum creatinine level of 2.8 mg/dL. All 15 patients presented with proteinuria (mean urinary protein excretion, 5.6 g/24 h). Eleven patients (73%) presented with nephrotic-range proteinuria and 8 (53%) with nephrotic syndrome. Histopathologic findings showed nodular glomerulosclerosis (100%), moderate to severe arterio-arteriolosclerosis (100%), and glomerular basement membrane thickening (100%). Immunofluorescence and electron microscopy studies had no other specific findings. Our results confirm previous studies of a close association of hypertension and smoking with idiopathic nodular glomerulosclerosis. A significantly higher incidence of obesity and overweight in patients with idiopathic nodular glomerulosclerosis suggests that increased body mass index may also contribute to the development and progression of idiopathic nodular glomerulosclerosis.

Idiopathic nodular glomerulosclerosis

Idiopathic nodular glomerulosclerosis is an unusual entity with light microscopic and ultrastructural features similar to those of nodular diabetic glomerulosclerosis but without evidence of abnormal glucose metabolism. We report 2 patients whose renal biopsies showed nodular glomerulosclerosis with afferent and efferent arteriolosclerosis, glomerular basement membrane thickening, focal mesangiolysis and capillary microaneurysm formation, and who had no evidence of abnormal glucose metabolism or other features of diabetes mellitus. Review of the literature shows that, of the 27 reported cases of idiopathic nodular glomerulosclerosis (not including the 2 cases reported herein), 11 showed evidence of abnormal glucose metabolism or were frankly diabetic. Of the remaining 16 cases with normal serum blood glucose measurements, 3 had diabetic retinopathy and 1 had a delayed insulin response curve. The cause and pathogenesis of the glomerular nodules are discussed, and it is suggested that arteriolar stenosis and glomerular ischemia may be involved in the development these lesions.