RPGN is a nephrologic emergency, and one of the more exciting consult cases for nephrologists to participate in. Much like dealing with a stroke or heart attack, delays in initiating therapy can lead to substantially worsened outcomes. Prompt initiation of therapy can be exceptionally challenging in RPGN, as even patients with advanced renal compromise may feel clinically well (as opposed to a stroke or a heart attack), and convincing them to accept aggressive therapies such as plasma exchange can be tough. Furthermore, for patients who present acutely, we don’t always have as much data as we would like to help make a decision. Unfortunately, waiting for renal biopsy results or serologies to come back before making the decision to treat glomerulonephritis can result in costly delays.
For this reason, any patient suspected of acute RPGN–defined as having an acutely elevated creatinine along with an active urine sediment–should be treated empirically.
Most patients in this situation can be treated solely with a steroid pulse–e.g., Solu-Medrol 0.5-1 gm iv qd x 3 days–while waiting for serologies to come back and scheduling a renal biopsy.
However, the presence of some specific clinical symptoms–pulmonary hemorrhage, CNS vasculitis, or mononeuritis multiplex–warrants a more aggressive empiric approach. In addition to the steroid pulse, we typically initiate urgent plasma exchange and often consider beginning Cytoxan right off the bat.