Referral criteria from primary care - proteinuria

• in general referral to a nephrologist is indicated if significant proteinuria (protein:creatinine ratio> 100 mg/mmol)
  • however proteinuria > 50 mg/mmol may be significant if other features of renal disease are present (e.g. impairment of renal function, coexistent microscopic haematuria, hypertension, features indicating an underlying systemic disease) (1)
  • other guidance suggests referral for protein:creatinine ratio >100 mg/mmol, or >45 mg/mmol if co-existing microscopic haematuria or estimated GFR <60mL/min (2)
    • prot/creat ratio at levels <= 45mg/mmol then manage as Chronic Kidney Disease (CKD), according to stage
  • if referring a patient for nephrology review then consider initiating other investigations such as renal tract ultrasonography, immunology (serum and urine protein electrophoresis, antinuclear antibodies, antineutrophil cytoplasmic antibodies, complements), and hepatitis B and C serology

Reference:

1. Haynes J, Haynes R. Proteinuria. BMJ 2006; 332:284.
2. http://www.renal.org/