Diagnosis

Tests to diagnose lupus nephritis include:

• Blood and urine tests. In addition to standard blood and urine tests, you may be asked to collect your urine for an entire day. These tests measure how well your kidneys are working.
• Kidney biopsy. A biopsy — where your doctor removes a small section of kidney tissue for lab analysis — is the most definitive test for diagnosing lupus nephritis. It can also help determine how severe your disease is.