Do you recommend obtaining a vasculitis work up for all patients seen for chronic kidney disease who are without a kidney biopsy?  

I don't. There is a false positivity rate with ANCA testing which can complicate management, especially if the patient has diseases such as inflammatory bowel disease or rheumatoid arthritis. I would only check ANCA levels if the patient has hematuria, worsening renal function, or some other issue t...