Acute
interstitial nephritis (AIN) is characterized by
inflammation of the renal interstitium and usually occurs in a temporal relationship with the medication. We present a case of an Asian male who had nephrotic range
proteinuria and presented with
acute kidney injury. The patient reported an acute change in physical appearance and symptomatology after the ingestion of a single dose of
sildenafil. Renal biopsy was notable for
minimal change disease (MCD) with acute and chronic
interstitial nephritis. Renal replacement and
glucocorticoid therapy were initiated. Renal recovery within six weeks permitted discontinuation of dialysis. AIN superimposed on MCD is a known association of
NSAID induced nephropathy. The temporal association and the absence of any new drugs suggest that the AIN was most likely due to the
sildenafil.
NSAIDs are less likely to have caused the AIN given their remote use. The ease of
steroid responsiveness would also suggest another cause as
NSAID induced AIN is often
steroid resistant. The MCD was most likely idiopathic given the lack of temporal association with a secondary cause. As the number of
sildenafil prescriptions increases, more cases of AIN may be identified and physician awareness for this potential
drug disease association is necessary.