Definition of Post-streptococcal glomerulonephritis (GN):

Post-streptococcal glomerulonephritis (GN) is a disorder of the kidneys that occurs after infection with certain strains of Streptococcus bacteria.

Causes, incidence, and risk factors:

Post-streptococcal GN is a form of glomerulonephritis. It is the result of an infection, not of the kidneys, but of a completely different area, such as the skin or throat, with a specific type of Group A beta hemolytic streptococcus bacteria.

The strep bacterial infection causes the tiny blood vessels called glomeruli in the kidneys to become inflamed, making the kidneys less able to filter and control the content of the urine.

Post-streptococcal GN is uncommon these days because infections that can lead to the disorder are commonly treated with antibiotics. The disorder may develop 1 - 2 weeks after an untreated throat infection, or 3 - 4 weeks after a skin infection.

It may occur in people of any age, but most often occurs in children ages 6 - 10. Although skin and throat infections are not uncommon in children, post-streptococcal glomerulonephritis is a rare complication of these infections.

Risk factors include:

• Strep throat
• Streptococcal skin infections (such as impetigo)