Definition & Overview

Nephritis refers to a medical condition characterized by an inflammation of the kidneys. The kidneys are some of the most hard-working organs in the body, aside from the heart. They filter around 50 gallons of blood on a daily basis, 5 gallons of which are waste products that are excreted from the body through urine.

When the kidneys function normally, the rest of the body is continuously supplied with “clean” oxygen-rich blood. However, when the kidneys become inflamed, they are unable to effectively filter the blood. If not treated, the kidneys go into a critical phase and ultimately fail. Kidney failure is a serious condition because waste products build up in the blood, poisoning other organs.

To prevent this from happening, the patient needs to undergo dialysis, which is a procedure that involves performing the functions of the kidneys through mechanical means. However, a patient will not be able to last through dialysis alone. Eventually, the kidneys will need to be replaced with healthy ones through a kidney transplant.

There are different types of nephritis. Each type is based on the part of the kidney that has been affected with the condition. The three main areas commonly affected are the glomeruli, tubule, and interstitial renal tissue.

  • Glomerulonephritis – This condition refers to the inflammation of the tiny capillaries in the kidneys called glomeruli, which task is to filter blood. When they become inflamed, they are unable to effectively filter the blood.

  • Interstitial Nephritis - If the inflammation does not affect the glomeruli, it will likely affect the area between the nephrons called the renal interstitium, which then results in a condition called interstitial nephritis, sometimes referred to as tubulointerstitial nephritis.

  • Pyelonephritis – The waste products excreted from the blood are passed on to the bladder through tubes called ureters. In some cases, inflammation begins at the bladder and travels up the ureters to the kidneys. This condition is referred to as pyelonephritis.

Cause of Condition

Each type of nephritis has its own set of causes.

The exact causes of glomerulonephritis are yet to be identified. However, doctors and researchers have identified several factors that may contribute to the infection, such as immune system disorders, history of cancer, abscess that forms from other parts of the body and is transported to the kidneys via blood circulation.

Pyelonephritis is mostly caused by the bacteria escherichia coli (e. coli). E. coli resides in the intestines and can cause infections in the kidneys. Other than e. coli, the other known causes of pyelonephritis are kidney stones, the use of an cystoscope to view the inside of the bladder, and actual surgery on the bladder, ureters, or kidneys.

Interstitial Nephritis is mostly caused by an allergic reaction to certain medications. Taking medications for a long period and having low levels of potassium in the blood are also known causes.

Other than knowing the causes of nephritis, it’s also important to determine if you’re at risk of developing the condition. The primary risk factors of nephritis are:

  • A family history of kidney diseases
  • The presence of immune system disorder
  • Over indulging in pain medications
  • Have recently undergone urinary tract surgery

Key Symptoms

Although there are different types of nephritis, which are also caused by different factors, the symptoms they display are often similar. The most common symptoms are:

  • Fever
  • Hypertension
  • Cloudy urine with blood or pus
  • Abdominal pain that reaches the kidney area
  • Urinating frequently, but with difficulty each time
  • Swelling (edema), especially in the upper and lower extremities and facial area
  • Frequent vomiting

The above symptoms are not only common on all the types of nephritis, but they are also present in other diseases and medical disorders. It’s important to consult your doctor if you experience any of these symptoms on a regular basis.

Who to See & Types of Treatment Available

Your primary health care provider is the first person to consult about the symptoms you’re experiencing. Because these symptoms are also present in a wide variety of illnesses, your doctor will have to perform several exams and obtain a detailed medical history and history of diseases in your family before making a diagnosis.

If your doctor suspects nephritis or that the symptoms are mostly associated with a problem in your kidneys, you’ll likely be referred to a specialist called a urologist.

The urologist will have you undergo more exams and blood tests to confirm the presence of nephritis or to determine the exact cause of the condition. Some of the exams are the following:

  • Kidney biopsy – a sample of kidney tissue is harvested and studied in a laboratory
  • CT Scan – detailed images of your abdomen and pelvic area will help the doctor diagnose the condition
  • Urine and blood tests – bacteria and infections will result in abnormal urine and blood tests readings

Once the doctor has determined the presence of nephritis and has been able to diagnose the exact causes of the condition, you’ll undergo treatment. The doctor will most likely treat the underlying cause of the condition. If the cause cannot be identified, certain medications will be prescribed to treat kidney infections.

The most common medications used in the treatment of infections are painkillers and antibiotics. For patients who are hypertensive, medications to control the blood pressure will also be prescribed. If it was determined that the infections are caused by a hyperactive immune system or a disorder of the immune system, immune system suppressants, such as corticosteroids, will be given to the patient.

Other than medical treatment, the patient must make critical lifestyle changes to help fight off the infection. Such changes would include, increasing water intake and reducing sodium intake. Water helps the kidneys function better and remove waste products from the blood. Reducing sodium will reduce the risk of water retention, which can result in complications, such as edema (swelling) in different parts of the body and facial area.


  • Neilson EG. Tubulointerstitial diseases. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 123.
  • Remuzzi G, Perico N, DeBroe ME. Tubulointerstitial diseases. In: Brenner BM, ed. Brenner and Rector's The Kidney. 8th ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 33.
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