Protein in Urine (Isolated Proteinuria): Diagnostic Tests

Obligatory medical device diagnostics.

  • Renal ultrasonography (ultrasound of the kidneys; includes the urinary tract).
    • [Acute glomerulonephritis: renal enlargement, cortical widening, and echogenicity increase of the renal cortex.
    • Chronic glomerulonephritis: rather reduced kidneys, narrowed renal cortex and increased echogenicity and decreased corticomedullary differentiation.
    • Nephrotic syndrome: significantly enlarged kidneys, marked increase in parenchymechogenicity]

Optional medical device diagnostics – depending on the results of the history, physical examination, laboratory diagnostics and mandatory medical device diagnostics – for differential diagnosis.

  • Radiographs of thoracic organs and skeleton to exclude osteolysis (spatially circumscribed dissolution or degeneration of bone tissue).
  • Computed tomography (CT) of the abdomen (abdominal CT) for further diagnosis.
  • Renal biopsy (tissue sampling from the kidney); indicated only if it leads to therapeutic consequences!
    • Large proteinuria (protein excretion of > 1 g/m 2KOF/d), persistent.
    • Proteinuria associated with hematuria (blood or erythrocytes (red blood cells in urine) of glomerular origin and/or renal function impairment (glomerular filtration rate (GFR) < 80 ml/m 2 KOF/min)
    • Indication of vascular systemic disease.
    • Nephrotic syndrome (for definitive diagnosis, treatment planning, prognosis assessment), rapidly progressive glomerulonephritis, suspected malignant kidney disease