This paper describes a case report of acute interstitial nephritis associated with Bufferin(R). A 15-year-old girl were referred to our hospital due to fever and renal dysfunction. Laboratory findings showed elevation of serum BUN and creatinine, and increased urinary β2-MG excreation. Light microscopic findings of her renal biopsy specimen revealed edema and numerous inflammatory cells in the interstitium, and minor alterations in glomeruli. The interstitial infiltrates consisted mainly of T cells and also monocytes/macrophages. Interstitial cells were labelled with antibodies to interleukin (IL)-1 and tumor necrose factor (TNF). Bufferin(R) was positive by lymphocyte stimulation test . Thus, we considered that this drug was causative in this case. This observation suggests the participation of cell -mediated immune injury in drug induced acute interstitial nephritis .
