Acute proliferative glomerulonephritis or PSAGN (PostStreptococcAl GlomeruloNephritis) is an inflammatory disease of the small blood vessels of the kidneys. Although it can be caused by any infection, it is most commonly caused by streptococcus. When antibodies are formed against the streptococcus, this can trigger an autoimmune reaction in the kidneys which leads to the inflammation. Like many kidney diseases, it is characterized by blood in the urine, decreased urine output, high blood pressure and a general feeling of malaise. It's more common in children than adults.
PSAGN should be suspected when any evidence of kidney dysfunction occurs in a patient with a likely infection. However, diagnosis is not straightforward as about a dozen other kidney diseases can cause glomerulonephritis. The usual path to confirmation is a biopsy, tests for complement proteins, radiology, and blood tests.
Once detected, treatment focuses on managing the condition until the patient recovers. Generally, the patient's blood pressure is managed and in most cases salt is removed from the diet. However, the condition can be deadly, although deaths from the condition are slowly becoming less common.