Inflammation of the filtering units in both kidneys. Injury to the glomeruli impairs the removal of waste products, water, and salt from the bloodstream, which can cause serious complications. Glomerulonephritis is one of the most frequently seen causes of chronic kidney failure.
Certain types of glomerulonephritis arise by the immune system making antibodies to get rid of microorganisms (often infectious bacteria, like those that cause streptococcal infections of the throat). The antibodies combine with bacterial antigens to create particles called immune complexes. These particles then circulate in the bloodstream and become trapped in the glomeruli, starting an inflammatory process that can impair the glomeruli and stop them from working as they should. Glomerulonephritis also arises in certain autoimmune disorders, such as systemic lupus erythematosus. Infectious diseases such as schistosomiasis and malaria are causes in tropical countries.
Mild glomerulonephritis can sometimes cause no symptoms, and is only discovered during routine urine testing; however, the condition can remain undetected until the kidney damage has reached an later stage and accrued waste products have started to cause symptoms.
Certain people develop symptoms unexpectedly. They can undergo a dull ache over the kidneys. The urine can become bloodstained because, when injured, the glomeruli let red blood cells escape into the urine. Protein can also be lost into the urine, causing odema; this is a frequently seen condition in affected children. Hypertension (high blood pressure) is a possibly serious complication. Long term glomerulonephritis is a common cause of chronic kidney failure.
Diagnosis involves urinalaysis (the chemical and microscopic analysis of urine), kidney function tests, ultrasound scanning of the kidneys and in many cases, kidney biopsy.
Treatment of glomerulonephritis is often administered in hospital and relies on the severity and cause of the disease. Children with nephritic syndrome often respond to corticosteroid drugs.
Adults usually respond less favourably to treatment. However kidney failure can sometimes be stopped or delayed. Drugs can be prescribed to control hypertension, and a personalised diet can be given to lessen the workload on the kidneys. Temporary dialysis can be needed to help get rid of waste products from the blood.
Some people with severe glomerulonephritis respond to treatment with immunosuppressant drugs (which lessen the activity of the immune system); some may undergo plasmapheresis (a procedure that gets rid of immune complexes and other harming substances in the blood stream).