Commonest stone in case of UTI -

Ans is 'a' ie Phosphate Phosphate or struvite stones are infection stones associated with urea splitting organisms i.e. Proteus, Pseudomonas, Providincia, Klebsiella, Staphylococci and Mycoplasma. The high ammonium concentration desired from urea-splitting organisms results in an alkaline urinary pH, reauired for the precipitation of phosphate crystals.