Which finding is characteristic of nephrotic syndrome on urinalysis under polarized light?

• A. Lipiduria with Maltese crosses
• B. Hematuria
• C. Bacteria
• D. Crystals

Answer: (A)

Nephrotic syndrome often causes lipiduria, where lipid droplets circulate in the urine due to marked protein loss and altered liver lipoprotein production. When a urine sample is examined under polarized light, these lipid droplets are birefringent and can form a Maltese cross pattern, a classic sign of lipiduria from nephrotic syndrome. This cross arises from the organized, cholesterol ester–rich lipids within the droplets aligning in a way that diffracts polarized light into a cross shape.

Hematuria, bacteria, and crystals are not characteristic findings of nephrotic syndrome. Hematuria suggests a nephritic process or other pathology, bacteria point to infection, and crystals are typical of stone disease or crystal-induced nephropathy, not the lipid-rich urine seen in nephrotic states.