Interstitial nephritis is a form of nephritis which affects the interstitium of the kidneys surrounding the tubules of the nephrons. The spaces between the kidney tubules become inflamed and swollen. The interstitial nephritis can affect the kidneys' function, including their ability to filter waste, eventually ending in kidney failure. It can be either acute or chronic.
The acute interstitial nephritis begins suddenly and is often caused by side effects of certain drugs. This form of the disease may be more severe and more likely to lead to chronic or permanent kidney damage in elderly people.
Common causes of interstitial nephritis include infection, or reaction to medication like analgesic or antibiotics. Reaction to medications causes 71% to 92% of cases. Both acute and chronic interstitial nephritis can also be caused by a bacterial infection in the kidneys, known as pyelonephritis.
Symptoms of interstitial nephritis may include: blood in the urine, increased or decreased urine output, fever, swelling of the body, rash, mental status changes such as drowsiness and confusion, nausea and vomiting, blood in urine.