The condition of a 50-year-old obese female with a 5-year history of mild hypertension controlled by a thiazide diuretic is being evaluated because proteinuria was noted during her routine yearly medical visit. Physical examination disclosed a height of 167.6 cm , weight of 91 kg , blood pressure of 130/80 mmHg, and trace pedal edema. (AIIMS Nov 2012)
Laboratory values are as follows:
Serum creatinine: 1.2 mg/dL
BUN: 6.4 mmol/L (18 mg/dL)
Creatinine clearance: 87 mL/min
Urinalysis: pH 5.0; specific gravity 1.018; protein 3+; no glucose; occasional coarse granular cast
Urine protein excretion: 5.9 g/d
A renal biopsy demonstrates that 60% of the glomeruli have segmental scarring by light microscopy, with the remainder of the glomeruli appearing unremarkable.
The most likely diagnosis is
|B||focal and segmental sclerosis|
|C||minimal-change (nil) disease|
a. The characteristic pattern of focal (not all glomeruli) and segmental (not the entire glomerulus) glomerular scarring is shown.
b. The history and laboratory features are also consistent with this lesion: some associated hypertension, diminution in creatinine clearance, and a relatively inactive urine sediment.
c. The “nephropathy of obesity” may be associated with this lesion secondary to hyperfiltration; this condition may be more likely to occur in obese patients with hypoxemia, obstructive sleep apnea, and right-sided heart failure.
d. Hypertensive nephrosclerosis exhibits more prominent vascular changes and patchy, ischemic, totally sclerosed glomeruli. In addition, nephrosclerosis seldom is associated with nephrotic-range proteinuria. Minimal-change disease usually is associated with symptomatic edema and normal-appearing glomeruli as demonstrated on light microscopy.
e. This patient’s presentation is consistent with that of membranous nephropathy, but the biopsy is not.
f. With membranous glomerular nephritis all glomeruli are uniformly involved with sub epithelial dense deposits.