Nephritis is

inflammation Inflammation (from ) is part of the biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. The five cardinal signs are heat, pain, redness, swelling, and loss of function (Latin ''calor'', '' ...

of the

kidneys In humans, the kidneys are two reddish-brown bean-shaped blood-filtering organs that are a multilobar, multipapillary form of mammalian kidneys, usually without signs of external lobulation. They are located on the left and right in the retro ...

and may involve the glomeruli, tubules, or interstitial tissue surrounding the glomeruli and tubules. It is one of several different types of nephropathy.

Types

* Glomerulonephritis is inflammation of the glomeruli. Glomerulonephritis is often implied when using the term "nephritis" without qualification. * Interstitial nephritis (or tubulo-interstitial nephritis) is inflammation of the spaces between renal tubules.

Causes

Nephritis can often be caused by infections and toxins, but it is most commonly caused by autoimmune disorders that affect the major organs like kidneys. * Pyelonephritis is inflammation that results from a urinary tract infection that reaches the renal pelvis of the kidney. *

Lupus nephritis Lupus nephritis is an inflammation of the kidneys caused by systemic lupus erythematosus (SLE) and childhood-onset systemic lupus erythematosus which is a more severe form of SLE that develops in children up to 18 years old; both are autoimmune d ...

is inflammation of the kidney caused by

systemic lupus erythematosus Lupus, formally called systemic lupus erythematosus (SLE), is an autoimmune disease in which the body's immune system mistakenly attacks healthy tissue in many parts of the body. Symptoms vary among people and may be mild to severe. Common ...

(SLE), a disease of the

immune system The immune system is a network of biological systems that protects an organism from diseases. It detects and responds to a wide variety of pathogens, from viruses to bacteria, as well as Tumor immunology, cancer cells, Parasitic worm, parasitic ...

. * Athletic nephritis is nephritis resulting from strenuous exercise. Bloody urine after strenuous exercise may also result from march hemoglobinuria, which is caused by trauma to

red blood cell Red blood cells (RBCs), referred to as erythrocytes (, with -''cyte'' translated as 'cell' in modern usage) in academia and medical publishing, also known as red cells, erythroid cells, and rarely haematids, are the most common type of blood cel ...

s, causing their rupture, which leads to the release of hemoglobin into the urine.

Mechanism

Nephritis can produce glomerular injury, by disturbing the glomerular structure with inflammatory cell proliferation. This can lead to reduced glomerular blood flow, leading to reduced urine output (

oliguria Oliguria or hypouresis is the low output of urine specifically more than 80 ml/day but less than 400ml/day. The decreased output of urine may be a sign of dehydration, kidney failure, hypovolemic shock, hyperosmolar Hyperglycemic Nonketotic Syndro ...

) 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 Hypertension, also known as high blood pressure, is a Chronic condition, long-term Disease, medical condition in which the blood pressure in the artery, arteries is persistently elevated. High blood pressure usually does not cause symptoms i ...

. As the kidneys inflame, they begin to excrete needed protein from the affected individual's body into the urine stream. This condition is called proteinuria. Loss of necessary protein due to nephritis can result in several life-threatening symptoms. The most serious complication of nephritis can occur if there is significant loss of the proteins that keep blood from clotting excessively. Loss of these proteins can result in blood clots, causing sudden stroke.

Diagnosis

The diagnosis depends on the cause of the nephritis, and in the case of

lupus nephritis Lupus nephritis is an inflammation of the kidneys caused by systemic lupus erythematosus (SLE) and childhood-onset systemic lupus erythematosus which is a more severe form of SLE that develops in children up to 18 years old; both are autoimmune d ...

blood tests A blood test is a laboratory analysis performed on a blood sample that is usually extracted from a vein in the arm using a hypodermic needle, or via fingerprick. Multiple tests for specific blood components, such as a glucose test or a cho ...

, X-rays and an ultrasound can help ascertain if the individual has the condition.

Treatment

Nephritis and nephrosis world map - DALY - WHO2004

Treatment (or management) of nephritis depends on what has provoked the inflammation of the kidney(s). In the case of lupus nephritis, hydroxychloroquine could be used.

Prevalence

Nephritis represents the ninth-most-common cause of death among all women in the US (and the fifth leading cause among non-

Hispanic The term Hispanic () are people, Spanish culture, cultures, or countries related to Spain, the Spanish language, or broadly. In some contexts, Hispanic and Latino Americans, especially within the United States, "Hispanic" is used as an Ethnici ...

black women). Worldwide, the highest rates of nephritis are 50–55% for African or Asian descent followed by Hispanic at 43% and Caucasian at 17%. The average age of an individual diagnosed with kidney inflammation (in this case, lupus nephritis) is 28.4 years old.

References

External links

{{Authority control Inflammations Kidney diseases