A man with a urinary catheter develops a urinary infection with alkaline urine and struvite stones. Which organism produces urease and causes this?
Answer and explanation
Correct answer: C. Proteus mirabilis
- Step 1: Urease splits urea into ammonia, which raises the pH. Step 2. The alkaline urine causes magnesium ammonium phosphate (struvite) stones. Answer: Proteus mirabilis. Why not the others: E. coli does not produce urease, and the other organisms do not cause struvite stones.
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