This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous, Subject name: Surgery
[{'content': 'Proteus infection leads to \nSelect and explain. \nA. Struvite stones, B. Uric acid stones, C. Pigment stones, D. Calcium/Cholestrol stones', 'role': 'user'}, {'content': 'Answer: A \nExplanation: (A) Struvite stones # Struvite stones are infectious stones composed of magnesium ammonium phosphate.> Struvite stones are common stones seen in SCI population, and they are caused by ureage producing bacteria.> Most common are Proteins, Psuedomonas, klebsiella, peosidentia, E.coli, Staphylococcus epidermidis, and ureaplasma urease catalyses break down of urea and water to ammonium and bicarbonate. The bicarbonate produces alkaline urine having a pH level greater than 7.2.> Alkaline urine facilitates the precipitation and crystailzation of magnesium ammonium phosphate , calcium carbonate, calcium phosphate.', 'role': 'assistant'}]