Interstitial Nephritis

What is interstitial nephritis?

Interstitial nephritis (say: "in-ter-stih-shul nef-rye-tus") is a kidney disorder. The kidneys are a pair of organs located just behind the stomach. They filter waste materials and extra fluid from the body in the form of urine. Interstitial nephritis reduces your kidneys’ ability to filter properly. In some cases, it may cause kidney failure. In kidney failure, waste and extra fluid build up and can cause problems with your heart, brain, lungs and other organs. It can lead to serious illness or death.

What causes interstitial nephritis?

Interstitial nephritis can be caused by an infection, the use of a medicine or certain health conditions that affect the immune system, such as lupus.

Infections associated with interstitial nephritis include herpes, mumps, hepatitis C, syphilis and human immunodeficiency virus (HIV). 

Medicines commonly associated with interstitial nephritis include certain antibiotics, such as penicillin, sulfonamides and cephalosporins. Many nonsteroidal anti-inflammatory drugs (NSAIDs) and certain diuretics (water pills) are also associated with interstitial nephritis. Interstitial nephritis may occur 2 or more weeks after you start a medicine. Talk to your doctor if you have any questions about a medicine you are taking.

How can my doctor tell if I have interstitial nephritis?

Your doctor will check your medical history and ask if you have experienced any of the following symptoms:

• Increased or decreased urine output
• Blood in your urine
• Nausea or vomiting
• Fever or rash
• Changes in mental status, such as drowsiness or confusion
• Swelling of any area of your body
• Weight gain (from extra fluid in your body)

If you have experienced one or more of these symptoms, your doctor may test your urine (called a urinalysis) and your blood.

How is interstitial nephritis treated?

Your doctor will deal with the cause of interstitial nephritis and treat your symptoms. He or she will treat any infection that may have caused the illness. If a medicine is causing your interstitial nephritis, your doctor may have you stop taking the medicine or may prescribe a different one. In some cases, medicines called corticosteroids may help interstitial nephritis.

Some people who have interstitial nephritis may need to have kidney dialysis. In dialysis, a machine does the work of your kidneys. This is usually only necessary for a short time.

Source

Diagnosis and Management of Acute Interstitial Nephritis (American Family Physician June 15, 2003, http://www.aafp.org/afp/20030615/2527.html)