An update on purple urine bag syndrome

Yoshiro Hadano,¹ Taro Shimizu,² Shimon Takada,³ Toshiya Inoue,⁴ Sumire Sorano<sup>5

1</sup>Department of General Internal Medicine and Infectious Diseases, Rakuwakai Otowa Hospital, Yamashina-ku, Kyoto, Japan; ²Rollins School of Public Health, Emory University, Atlanta, GA, USA; ³Department of General Internal Medicine, Osaka City General Hospital, Miyakojima-ku, Osaka, Japan; ⁴Department of Emergency Medicine, Urasoe General Hospital, Urasoe-city, Okinawa, Japan; ⁵Kobe University School of Medicine, Kusunokicho, Chuoku, Kobe, Japan

Abstract: Purple urine bag syndrome is characterized by the urinary drainage bag turning purple in patients on prolonged urinary catheterization, especially those in the bedridden state. It is associated with bacterial urinary tract infections caused by indigo-producing and indirubin-producing bacteria, usually affects women, and is associated with alkaline urine, constipation, and a high bacterial load in the urine. Almost all patients with purple urine bag syndrome are catheterized due to significant disability, and the urinary pH is 7.0 or more. In general, intensive treatment with antibiotics is not recommended. Purple urine bag syndrome per se almost always appears to be asymptomatic and harmless. However, caution is needed, because some cases have been reported to show progression to severe disease states, so further research into the morbidity and mortality of this infection is warranted.

Keywords: purple urine, urinary catheterization, geriatrics, urinary tract infection