What is the most expected lab finding in a patient with nephrotic syndrome, significant proteinuria, and low serum protein (hypoproteinemia) of 2.5 g/dL?

Hypercholesterolemia (Answer D)

In a patient with nephrotic syndrome presenting with significant proteinuria and severe hypoproteinemia (serum protein 2.5 g/dL), hypercholesterolemia is the most expected laboratory finding among the options provided. 1, 2

Pathophysiological Basis

Nephrotic syndrome is characterized by the classic triad of massive proteinuria (>3.5 g/24 hours), hypoalbuminemia (<3.0 g/dL), and edema, with hyperlipidemia being a cardinal associated feature. 1, 3

• Hypercholesterolemia occurs as a compensatory hepatic response to the severe loss of plasma proteins through the damaged glomerular filtration barrier. 2
• The liver increases synthesis of lipoproteins in an attempt to maintain oncotic pressure, resulting in elevated total cholesterol, LDL-cholesterol, and triglycerides. 1
• This metabolic complication contributes to a four-fold increased risk of accelerated coronary heart disease in nephrotic patients. 1

Why the Other Options Are Less Expected

Hypokalemia (Option A)

• Nephrotic syndrome does not typically cause hypokalemia as a primary manifestation. 1
• Potassium disturbances are not characteristic laboratory findings in the nephrotic syndrome itself, though diuretic therapy used to manage edema could secondarily cause hypokalemia. 1

Hypernatremia (Option B)

• Nephrotic syndrome patients typically have normal or low serum sodium due to water retention and dilutional effects, not hypernatremia. 2
• The activation of the epithelial sodium channel (ENaC) leads to sodium and water retention, causing edema rather than hypernatremia. 4

Metabolic Acidosis (Option C)

• Metabolic acidosis is not a characteristic feature of nephrotic syndrome. 1
• Acid-base disturbances are more typical of nephritic syndrome or advanced chronic kidney disease, not the nephrotic presentation. 2

Clinical Context

With a serum protein of 2.5 g/dL (indicating severe hypoalbuminemia), this patient has:

• Significantly increased thromboembolism risk (29% risk for renal vein thrombosis when albumin is this low). 1, 2
• Expected lipid panel abnormalities including elevated total cholesterol, LDL-C, and triglycerides. 1
• High likelihood of requiring lipid assessment as part of standard diagnostic evaluation. 1

Common Pitfall

Do not assume that all metabolic derangements occur in nephrotic syndrome—the syndrome has specific, predictable laboratory patterns dominated by protein loss and compensatory hepatic responses, not generalized electrolyte disturbances. 1, 2