Purple Urine

[[{"type":"media","view_mode":"media_crop","fid":"48539","attributes":{"alt":"","class":"media-image media-image-right","height":"235","id":"media_crop_2885547723692","media_crop_h":"0","media_crop_image_style":"-1","media_crop_instance":"5796","media_crop_rotate":"0","media_crop_scale_h":"0","media_crop_scale_w":"0","media_crop_w":"0","media_crop_x":"0","media_crop_y":"0","style":"float: right;","title":"EMresource.ORG","typeof":"foaf:Image","width":"314"}}]]A bedridden elderly woman with a history of dementia, Parkinson disease, and a chronic  indwelling Foley catheter is brought to the emergency department for evaluation of purple urine noted in her Foley bag. The patient denies any fever, vomiting, or weakness, but her lower abdomen is “uncomfortable.” She does not recall eating beets, blueberries, or anything purple recently.

Vital signs are normal. Physical examination finds a conversant elderly woman in no acute distress. Head and neck exam is unremarkable with a moist oropharynx. Lungs are clear and the heart is regular. There is no abdominal or flank tenderness and no peripheral edema. The Foley bag is shown at right.

 â–º What testing should be performed?  â–º What is the most likely cause for these findings?

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