Lipiduria

The presence of lipids in the urine, visualized as fatty casts or oval fat bodies on urine microscopy, reflecting increased glomerular permeability, lymphatic leakage, or systemic lipid mobilization.

Causes

• Nephrotic-range glomerular diseases causing heavy proteinuria

  • Diabetic nephropathy

  • Systemic lupus erythematosus (SLE) nephritis

  • Minimal change disease

  • Focal segmental glomerulosclerosis

  • Membranous nephropathy

• Fat embolism-related causes

  • Fat embolism syndrome

  • Major trauma with long bone fractures

  • Orthopedic surgery

  • Severe tissue injury

• Lymphatic causes

  • Chyluria due to lymphatic obstruction

  • Parasitic infections (e.g., filariasis)

  • Lymphatic fistula involving the urinary tract

  • Malignancy causing lymphatic obstruction

• Medication and toxins causing glomerular or tubular injury

  • Nephrotoxic antibiotics

  • Environmental toxins