Acute Interstitial Nephritis

First Things First (assess & treat for the following)

Suspect AIN if:

• There is an acute rise in the plasma creatinine concentration temporally related to an offending drug or infection.
• Triad of fever, rash and eosinophilia may be present (except in NSAID-induced AIN).
• Urine sediment that usually reveals white cells, red cells, white cell casts
• Eosinophilia & eosinophiluria in >75% of cases, w/ the exception of disease induced by NSAIDs
• Normal or only mildly increased protein excretion (< 1 g/day). Concurrent nephritic syndrome due to minimal change disease is often seen w/ NSAIDs & in selected cases induced by ampicillin, rifampin, interferon or ranitidine.

• Signs of tubulointerstitial damage such as Fanconi syndrome & renal tubular acidosis