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.

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

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/m² [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.