Why is this urine bag purple?

An 80-year-old female with a history of diabetes and chronic constipation presents to the emergency department with a purple urine bag. She is currently bedridden and uses an indwelling catheter. On examination, she is hypotensive and confused. Blood cultures are positive for Proteus vulgaris. Based on this patient’s presentation, which of the following antibiotics should be commenced?

A. Nitrofurantoin
B. Ciprofloxacin
C. Ceftriaxone
D. Piperacillin-tazobactam

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Christy Crisologo

    Christy Crisologo is SDN’s Editor-in-Chief. She earned her BA in Communications from Asbury University and lives in Texas with her husband (and primary connection to the medical world) and their two young children. 

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