What are infection stones?
Infection stones are composed of struvite.
Struvite stones only form in the presence of urinary infection with bacteria that possesses the enzyme urease, which converts urea to ammonium and bicarbonate, leading to the unique condition of high urine ammonium concentration with a high urine pH.
The bacteria most likely to possess urease are the Proteus species, although many other bacterial species may also possess urease. Escherichia coli, the most common urinary tract pathogen, does not possess urease.
Struvite stones can grow to fill the entire renal pelvis (staghorn stones) and may lead to recurrent infection and loss of kidney function.
Treatment of struvite stones requires complete surgical removal of the stone and a prolonged course of antibiotics.
