Proteinuria and Haematuria – an update Alex Heaton
What is normal? Normal 80 +/- 25 mg/day (<150 mg is quoted as upper normal limit). Adolescents up to 300 mg/day ( years, years)
Measurements of proteinuria Dipstick tests 24 hour urinary protein Urine protein/creatinine ratio Urine albumin/creatinine ratio
Why bother testing urine? Detection of renal disease Cardiovascular risk factor
Clinical significance of proteinuria Proteinuria on dipstick in healthy patient ? Any systemic disease, e.g hypertension, diabetes mellitus likely renal disease >1 gram a day likely renal disease >3.5 g/day likely glomerular disease
Protein in urine – what next? establish persistent proteinuria clinical assessment interpreting test results
Step 1. Establish persistent proteinuria proteinuria (1+ or more) exclude urinary infection repeat urinalysis after at least one week 1+ or more continuetrace or negative – no action
Step 2. Initial assessment if persistent proteinuria 1+ or more send early morning urine for albumin/creatinine ratio blood tests: U & Es, fasting glucose, cholesterol and albumin Check blood pressure
Step 3: What to do with an albumin/creatinine(mg/mmol) result <5 within reference range 5-30 does not indicate renal disease but consider cardiovascular risk factors check 6 monthly blood pressure and ACR. No need to refer to nephrology unless patient also has haematuria, severe hypertension, eGFR <60 or a systemic disease >70refer to Nephrology
Proteinuria - summary urine protein testing is worthwhile (vs blood) use dipstix to decide when to test further albumin : creatinine ratio instead of 24 hour collection. use ACR to decide who to refer
Haematuria frank haematuria – high yield on investigation microscopic haematuria + symptoms – high yield - symptoms – low or very low yield
Microscopic haematuria trace blood + no symptoms – no investigation 1+ or more, confirmed on repeat testing – investigate/refer?
Urology Referral male >40 years smoker industrial exposure to hydrocarbons chemotherapy = cystoscopy
Renal referral eGFR < 60 proteinuria (ACR >30) hypertension family history = nephrology
What tests? eGFR plain urinary tract X-ray ultrasound ? urine microscopy ? cytology
Summary - haematuria try to avoid testing asymptomatic patients most asymptomatic patients do not need referral? limited benefit from renal referral unless specific indication.