Purple urine bag syndrome is a rare manifestation of bacteriuria on bladder catheter: case report

Background Purple urine bag syndrome (PUBS) is a complication of bacterial colonisation of bladder catheters in which urine turns purple in the tubing, as well as in the catheter bag. This rare phenomenon can be very worrisome and stressful for the patients and their families, as well as for the healthcare team taking care of them. Recognising this complication is essential in order to avoid misdiagnosis and erroneous treatment. We report a case of PUBS in a 71-year-old female patient. Case presentation A 71-year-old woman with previous medical history of schizophrenia was admitted to the emergency department for anorexia and suspicion of psychotic decompensation. Acute urine retention and rectal faecal impaction were clinically suspected and confirmed by bladder ultrasound and rectal examination, respectively. The patient underwent bladder catheterisation as well as a rectal enema. The day after her admission, our medical team was approached by the nurse in charge of the patient because of purple urine in her catheter bag and tubing. The diagnosis of PUBS was made with the help of the Oxford urine chart. A dipstick urinalysis revealed alkaline urine (pH = 8), and the urine culture was subsequently positive for Proteus mirabilis, which is sensitive to quinolones, beta-lactams and nitrofurantoin. The bladder catheter was changed. The patient received empiric antibiotic therapy with Levofloxacin 500 mg once daily. After obtaining the antibiogram, the targeted antibiotic therapy was adapted with oral Cefuroxime 500 mg three times a day for a total duration of seven days of antibiotic therapy. There was no recurrence of purple urine. Conclusion PUBS is a rare complication of bacteriuria, which induces a purple colouration of the tubing as well as the catheter bag. It is a simple spot diagnosis, as there is no other known cause of purple urine. This is why we believe that the Oxford urine chart represents a very interesting and easily accessible tool to help clinicians to investigate any abnormal urine colour.

Urine pH Value and Bacteriology in Purple Urine Bag Syndrome

<b><i>Background:</i></b> Purple urine bag syndrome (PUBS) is an unusual phenomenon in patients with urinary tract infections. The urine of most of these patients has an alkaline pH. <b><i>Objective:</i></b> The goal of this study was to identify infectious bacteria and determine urinary pH in patients with PUBS and to evaluate their correlation. <b><i>Methods:</i></b> PubMed was searched using the term “Purple urine bag syndrome (PUBS)” for studies on this condition published from October 1980 to September 2019. Sixty-seven patients were identified and divided into those with urine cultures positive for Gram-positive bacteria (GPB; <i>n</i> = 3), Gram-negative bacteria (GNB; <i>n</i> = 45), and mixed Gram-positive and Gram-negative bacteria (MGPNB; <i>n</i> = 19). Age, gender, urinary pH, comorbidities (diabetes and uremia), fever, shock, and mortality were compared in the 3 groups. The correlation between urinary pH and type of bacteria in urine cultures was assessed by regression analysis. <b><i>Results:</i></b> Presentation of fever in PUBS accounted for 66.7, 11.1, and 5.3%, <i>p</i> &#x3c; 0.05, in GPB, GNB, and MGPNB. Regression analyses showed that <i>Pseudomonas aeruginosa</i> was associated with less alkaline urine (regression coefficient −0.936, <i>p</i> &#x3c; 0.05), whereas <i>Proteus</i> spp. was associated with more alkaline urine (regression coefficient 0.489, <i>p</i> = 0.04). GNB were the most predominant pathogens in patients with PUBS. <b><i>Conclusion:</i></b> In PUBS, urine pH and symptom presentation are different by variable bacteria. Fever is associated with urinary GPB. <i>Proteus</i> spp. correlates with more alkaline urine, whereas <i>Pseudomonas</i> spp. correlates significantly with less alkaline urine.

Purple urine bag syndrome: When the urine turns purple – An under diagnosed spot diagnosis

The Purple Urine Bag Syndrome (PUBS) is a rare condition in which the urine turns purple. It may occur in Urinary Tract Infections (UTIs) when bacteria metabolize dietary tryptophan to indole resulting in indigo (blue) and indirubin (red). This condition is mostly seen in elderly female patients with permanent urinary bladder catheterization. Patients, relatives and health professionals may be concerned about this discolouration, which is usually harmless. Medical management of PUBS involves frequent urinary bag change, antibiotic therapy and most importantly reassurance. We report an 89-years-old long-term catheterized female nursing home resident who was admitted to the emergency room because of a Community Acquired Pneumonia (CAP). After a few days of inpatient treatment her urine bag turned purple. Antibiotic therapy continued and the indwelling urinary catheter was changed resulting in clear urine. Keywords: Purple urine bag syndrome (PUBS); purple discolouration; urinary tract infection (UTI); long-term catheterization.