Acute tubulointerstitial nephritis is usually an allergic reaction of the kidney to a drug and if treated early is usually reversible & the patient recovers. The treatment is a short course (3-4 weeks) of steroids (omnacortil). The recovery will depend on the kidney biopsy findings and if there are any chronic changes in the biopsy, they usually are not reversible. In some patients the tubulo-interstitial nephritis is idiopathic (no cause found) or part of various systemic diseases like auto-immune disorders (systemic lupus erythematosus).