Abstract
Acute interstitial nephritis is an immunologically mediated disease, characterized by the presence of inflammatory cell infiltrate in the interstitium and renal tubules, which often leads to acute renal failure. The causes include drugs, accounting for more than half of the cases; infectious diseases and systemic diseases.
The clinical picture usually includes extrarenal manifestations of hypersensitivity reaction such as fever, rash and eosinophilia. Urine findings may be minimal, with only a small proteinuria, sterile pyuria, but also as a significant eosinophiluria and microscopic haematuria.
Severe tubulointerstitial involvement leads to acute kidney injury and need of renal replacement therapy. Renal biopsy not only correctly determines the diagnosis, but also assesses the severity of renal damage and influences treatment decisions.
The treatment of acute interstitial nephritis remains unchanged because of the lack of strong data. The treatment is still a subject of controversy in terms of corticosteroid use.
Immunosuppressive therapy seems to be indicated only in the cases of severe acute tubulointerstitial nephritis involving medium to high doses of corticosteroids for a maximum period of several weeks.