Protein in urine can be caused by kidney damage from diabetes or high blood pressure, infection, dehydration, or intense exercise. See a doctor for testing.
Normal
Healthy adults make under 150 mg of protein in urine a day.
Causes
- Kidney damage from diabetes or high blood pressure.
- Infection.
- Dehydration or strenuous exercise.
- Fever.
- Pregnancy (preeclampsia).
- Kidney disease.
Tests
Urinalysis, albumin to creatinine ratio.
Symptoms
Foamy urine, swelling.
See a doctor
For follow up testing.
Emergency
Pregnancy with headache and high blood pressure.
Normal versus abnormal
Healthy kidneys keep most protein in the blood. Normal urine protein is under about 150 mg per day, and the urine albumin-to-creatinine ratio (ACR) is under 30 mg/g. A ratio of 30 to 300 mg/g is moderately increased albuminuria, and over 300 mg/g is severely increased.
- Temporary proteinuria occurs with fever, intense exercise, dehydration and stress.
- Persistent proteinuria can be due to diabetes, high blood pressure, glomerulonephritis, lupus, preeclampsia in pregnancy, and heart failure.
- Multiple myeloma produces light chains that standard dipsticks may miss.
Tests and symptoms
A dipstick test is a screen, followed by a spot ACR or a 24-hour urine collection. Doctors repeat the test, check blood creatinine and eGFR, and sometimes order ultrasound or biopsy. Foamy urine, swelling in the legs or face and fatigue may occur in significant proteinuria. See a doctor for persistent protein, and urgently for protein with high blood pressure, headache and swelling in pregnancy.
Normal versus abnormal
Normal urine protein is below about 150 mg per day. Proteinuria can be temporary with fever, exercise or dehydration, or reflect kidney disease, diabetes or high blood pressure. The urine albumin to creatinine ratio above 30 mg/g is abnormal.
Tests and symptoms
Symptoms can include foamy urine and swelling. Doctors repeat testing and may check blood pressure, blood tests and imaging. Treatment targets the cause.
Normal and abnormal levels
Healthy kidneys keep most protein in the blood. Normal urine protein is below 150 mg per day, and an albumin to creatinine ratio under 30 mg per gram is normal. A dipstick showing trace or 1 plus can occur after exercise, fever, dehydration or standing for a long time. Persistent protein (proteinuria) over 3 months is a sign of possible kidney damage.
Causes and follow up
Causes include diabetes, high blood pressure, glomerulonephritis, lupus, preeclampsia in pregnancy, infections and multiple myeloma. Doctors repeat the test, do a 24 hour or spot ratio, check blood creatinine and eGFR, and may order imaging or biopsy. Treatment includes ACE inhibitors or ARBs, SGLT2 inhibitors for some patients, blood sugar and pressure control and reduced salt. Foamy urine, swelling in the legs or rapid weight gain need prompt evaluation.
Based on data from the National Kidney Foundation and the Mayo Clinic
