Urinary markers representing different sites of effects in the nephron
| Urinary marker | Site of effect | Reference range |
|---|---|---|
| Reference ranges are those quoted by the Health and Safety Laboratory (HSL), Sheffield for subjects of working age, and are corrected per mmol of urinary creatinine. | ||
| *Occasionally albuminuria can occur as a result of failure of tubular reabsorption. | ||
| Albumin* | Glomerular permeability | <3.5 mg/mmol |
| Transferrin | Glomerular permeability | <0.36 iu/mmol |
| Retinol binding protein (RBP) | Proximal tubular reabsorption | <22 μg/mmol |
| N-acetyl-β-glucosaminidase (NAG) | Proximal tubular damage (predominantly S1&2) | <1.25 iu/mmol |
| γ-glutamyl transferase (GGT) | Proximal tubular cell damage | <6.0 iu/mmol |
| Leucine aminopeptidase (LAP) | Proximal tubular brush border cell damage | <0.8 iu/mmol |
| α glutathione-S-transferase (α-GST) | Proximal tubular cell damage (predominantly S3) | <2.2 μg/mmol |
| π glutathione-S-transferase (π-GST) | Distal tubular cell damage | <5.8 μg/mmol |