Nephritis is

inflammation Inflammation (from la, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or irritants, and is a protective response involving immune cells, blood vessels, and molec ...

of the kidneys and may involve the glomeruli,

tubules In biology, a tubule is a general term referring to small tube or similar type of structure. Specifically, tubule can refer to: * a small tube or fistular structure * a minute tube lined with glandular epithelium * any hollow cylindrical body stru ...

, 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 Interstitial nephritis, also known as tubulointerstitial nephritis, is inflammation of the area of the kidney known as the renal interstitium, which consists of a collection of cells, extracellular matrix, and fluid surrounding the renal tubul ...

(or tubulo-interstitial nephritis) is inflammation of the spaces between renal tubules.

Causes

Nephritis is often caused by infections, and toxins, but is most commonly caused by autoimmune disorders that affect the major organs like kidneys. *

Pyelonephritis Pyelonephritis is inflammation of the kidney, typically due to a bacterial infection. Symptoms most often include fever and flank tenderness. Other symptoms may include nausea, burning with urination, and frequent urination. Complications ...

is inflammation that results from a urinary tract infection that reaches the

renal pelvis The renal pelvis or pelvis of the kidney is the funnel-like dilated part of the ureter in the kidney. It is formed by the covnvergence of the major calyces, acting as a funnel for urine flowing from the major calyces to the ureter. It has a muco ...

of the kidney. * Lupus nephritis is inflammation of the kidney caused by systemic lupus erythematosus (SLE), a disease of the

immune system The immune system is a network of biological processes that protects an organism from diseases. It detects and responds to a wide variety of pathogens, from viruses to parasitic worms, as well as cancer cells and objects such as wood splinte ...

. * 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), also referred to as red cells, red blood corpuscles (in humans or other animals not having nucleus in red blood cells), haematids, erythroid cells or erythrocytes (from Greek ''erythros'' for "red" and ''kytos'' for "hol ...

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) and retention of waste products (

uremia Uremia is the term for high levels of urea in the blood. Urea is one of the primary components of urine. It can be defined as an excess of amino acid and protein metabolism end products, such as urea and creatinine, in the blood that would be no ...

). 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 (HTN or HT), also known as high blood pressure (HBP), is a long-term medical condition in which the blood pressure in the arteries is persistently elevated. High blood pressure usually does not cause symptoms. Long-term high b ...

. 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, blood tests, 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'' ( es, hispano) refers to people, cultures, or countries related to Spain, the Spanish language, or Hispanidad. The term commonly applies to countries with a cultural and historical link to Spain and to viceroyalties for ...

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

{{Nephrology Inflammations Kidney diseases