What is interstitial nephritis?

Interstitial nephritis (say: in-ter-stih-shul nef-rye-tus) is a kidney disorder. The kidneys filter waste and extra fluid from the body. Interstitial nephritis reduces the kidneys’ ability to filter properly.

Interstitial nephritis is a serious condition, but it can be treated. However, in rare cases, it may cause kidney failure. When the kidneys fail, waste and extra fluid build up in the body and can cause problems with the heart, brain, lungs and other organs.

What are the symptoms of interstitial nephritis?

Your doctor will probably ask whether you have noticed any of the following signs and symptoms:

• Increased or decreased urine output
• Blood in your urine or dark urine
• Nausea or vomiting
• Fever or rash
• Changes in mental status, such as drowsiness or confusion
• Swelling of any area of your body
• Sudden weight gain (this can be caused by extra fluid in the body)

What causes interstitial nephritis?

Interstitial nephritis can be caused by the following problems:

• Infections
• A reaction to a medicine, such as certain antibiotics
• Too much of certain medicines (pain relievers, such as acetaminophen, aspirin or a non-steroidal anti-inflammatory drug [NSAID], or diuretics [water pills])

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?

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

How is interstitial nephritis treated?

Interstitial nephritis is caused by an underlying problem. If that problem is an infection, your doctor will treat the infection. If a medicine is the cause of interstitial nephritis, he or she will probably have you stop taking the medicine or prescribe a different one. In some cases, corticosteroids (medicines that reduce inflammation) may help. Dialysis, a treatment that uses a special machine to filter the blood, is sometimes necessary.

• What treatment is best for me?
• Should I stop taking my medicine?
• Will I need surgery?
• Should I see a urologist?
• Are there any medicines I should take?
• What is causing the interstitial nephritis?
• Will I need dialysis?
• If I need dialysis, will I have to do it for the rest of my life?
• Could this cause permanent damage to my kidneys?
• How often will I need to come in for follow-up visits?