Nephritis

Nephritis
Classification and external resources
MeSH	D009393

Nephritis is inflammation of the nephrons in the kidneys. The word "nephritis" was imported from Latin, which took it from Greek: νεφρίτιδα. The word comes from the Greek νεφρός - nephro- meaning "of the kidney" and -itis meaning "inflammation".

Subtypes

By main location of inflammation

• Glomerulonephritis is inflammation of the glomeruli. (When the term "nephritis" is used without qualification, this is often the condition meant.)
• Interstitial nephritis or tubulo-interstitial nephritis is inflammation of the spaces between renal tubules.

By cause

Nephritis is often caused by infections, toxins, and auto-immune diseases. It can be caused by infection, but is most commonly caused by autoimmune disorders that affect the major organs. For example, those with lupus are at a much higher risk for developing nephritis. In rare cases nephritis can be genetically inherited, though it may not present in childhood.

• Pyelonephritis is inflammation that results from a urinary tract infection that reaches the pyelum (pelvis) of the kidney.
• Lupus nephritis is an inflammation of the kidney caused by systemic lupus erythematosus (SLE), a disease of the immune system.
• Athletic nephritis is nephritis resulting from strenuous exercise. It may result in proteinuria, hematuria and cylinduria. In most persons these are transient findings that disappear within hours to days after the end of exercise. The findings generally increase by increasing severity and duration of physical stress. Hematuria after strenuous exercise may also result from march hemoglobinuria, which is caused by trauma to red blood cells, causing hemolysis and resultant release of hemoglobin into the blood. However, it is possible for athletic nephritis to be a result of the hemoglobin load on the kidneys caused by march hemoglobinuria.

Complications

Nephritis is the most common producer of glomerular injury. It is a disturbance of the glomerular structure with inflammatory cell proliferation. This can lead to reduced glomerular blood flow, leading to reduced urine output (oliguria) and retention of waste products (uremia). As a result, red blood cells may leak out of damaged glomeruli, causing blood to appear in the urine (hematuria). Low renal blood flow activates the renin-angiotensin-aldosterone system (RAAS), causing fluid retention and mild hypertension.

Nephritis is a serious medical condition which is the eighth highest cause of human death. As the kidneys inflame, they begin to excrete needed protein from the body into the urine stream. This condition is called proteinuria. Loss of necessary protein due to nephritis can result in several life-threatening symptoms. Most dangerous in cases of nephritis is the loss of protein that keeps blood from clotting. This can result in blood clots causing sudden stroke.

Epidemiology

Disability-adjusted life year for nephritis and nephrosis per 100,000 inhabitants in 2004.

  no data

  less than 40

  40-120

  120-200

  200-280

  280-360

  360-440

  440-520

  520-600

  600-680

  680-760

  760-840

  more than 840

See also

• Bright's Disease
• Goodpasture's syndrome
• Wegener's granulomatosis