Smoking-related glomerulopathy: expanding the morphologic spectrum

Area of Science:

• Nephrology
• Pathology
• Cardiovascular Medicine

Background:

• Chronic smoking and hypertension are risk factors for kidney disease.
• Smoking-related nodular glomerulopathy (SRNG) clinically and pathologically resembles diabetic nephropathy (DN).
• Diffuse mesangial sclerosis can occur in SRNG without nodules, similar to DN.

Purpose of the Study:

• To analyze the clinicopathologic features of non-diabetic patients with a history of smoking and kidney disease.
• To investigate the spectrum of glomerular injury in patients with smoking-related nephropathy.

Main Methods:

• Retrospective analysis of 10 non-diabetic patients diagnosed with diffuse mesangial glomerulosclerosis or SRNG between 2003-2012.
• Review of clinical data including smoking history, hypertension, and renal function (creatinine, proteinuria).
• Examination of renal biopsy findings, including glomerulosclerosis, glomerulomegaly, interstitial fibrosis, arteriosclerosis, arteriolar hyalinosis, and signs of chronic thrombotic microangiopathy (TMA).

Main Results:

• The study included 9 men aged 58-80 with significant smoking histories (20-58 pack-years) and hypertension.
• Patients presented with elevated creatinine (mean 1.9 mg/dl) and proteinuria (mean 3.9 g/24 h).
• Renal pathology showed global glomerulosclerosis, glomerulomegaly, interstitial fibrosis, arteriosclerosis, arteriolar hyalinosis, and prominent mesangial neovascularization. 80% showed features suggestive of chronic TMA.

Conclusions:

• Kidney biopsies in patients with proteinuria, renal insufficiency, smoking, and hypertension demonstrate mesangial glomerulosclerosis (diffuse or nodular).
• Chronic glomerular injury from smoking can lead to a chronic TMA appearance, even without nodule formation.
• These findings highlight the importance of considering smoking as a cause of nephropathy that mimics diabetic kidney disease.