Urinary T Cell Biomarker for Prediction in ANCA Glomerulonephritis

Urinary T lymphocytes may be predictive for clinical outcome in patients with ANCA associated glomerulonephritis (ANCA GN). The investigators hypothesize that the amount of CD4+ effector/memory T cells in urine at time of diagnosis predicts the outcome of patients with active ANCA GN after 6 months of therapy. In a prospective, six-months follow-up study patients' urine will be analysed by flow cytometry every 60 days (+/- 10d). Treatment will be performed to the discretion of the treating clinician. After 6 months of treatment response will be determined as either complete response or partial response.