Description:
From Merck Manual Online Medical Library
Nephritis is inflammation of the kidneys. It may be caused by a bacterial infection of the kidneys (pyelonephritis
(see Urinary Tract Infections: Kidney Infection (Pyelonephritis)) or exposure to a toxin. However, it more commonly develops
from an abnormal immune reaction, which can occur in two ways: (1) an antibody can attack either the kidney itself or a substance
that stimulates an immune reaction (antigen) attached to kidney cells, or (2) an antigen and antibody can combine somewhere
else in the body, forming an immune complex, and then attach to cells in the kidney.
Some types of nephritis involve infiltration of kidney tissues by white blood cells and deposits of antibodies.
In other types of nephritis, inflammation may consist of tissue swelling or scarring without white blood cells or antibodies.
Nephritis can occur anywhere in the kidneys.
Nephritis most often affects the tufts of microscopic blood vessels (glomeruli) with small pores through which
blood is filtered. Such inflammation is called glomerulonephritis.
There are three major types of glomerulonephritis: nephritic syndrome, nephrotic syndrome, and asymptomatic
proteinuria and hematuria syndrome. The three types are not exclusive; a person may have two types simultaneously, or have
one type that later develops into another type.
Nephritis may also involve the blood vessels within the kidneys. Inflammation of the blood vessels is called
vasculitis.
Symptoms and Signs
- No symptoms in about half of cases
- Swelling of the tissues (initially the face and around the eyes, later more prominent in the legs)
- Reduction in urine volume
- Dark urine (contains blood)
- Increase in blood pressure
- Headaches
- Drowsiness
- Visual disturbances
- Tiredness and general malaise (feeling ill)
- Nausea
- In rapidly progressive disease, loss of appetite, vomiting, abdominal pain and joint pain may occur
- Chronic nephritis may go unnoticed for years until symptoms of kidney failure appear: tiredness, itchy skin, nausea and
vomiting, shortness of breath
Links of Interest:
BBC Health
Health Scout
Kidney.org
