Risk factors of mortality in patients with purple urine bag syndrome

Abstract

Aim: Purple urine bag syndrome (PUBS) is rarely seen in clinical practice. Several studies have reported that PUBS is relatively benign in its clinical course, but this study aimed to identify risk factors for mortality related to PUBS. Materials and methods: In a PubMed search from October 1980 to August 2016, using the search term “Purple urine bag syndrome (PUBS)”, 106 articles (n = 174 cases) were identified. This study excluded 58 cases. Among them, 14 cases did not include information on patient sex and four cases did not include information on patient age. Thirty-seven cases did not report the white blood cell (WBC) count, shock, fever, or etiology. Three cases did not report patient survival. This study considered 116 PUBS cases. Chi-square tests were used to compare the survival and mortality groups. Results: In relative risk analysis, uremia (17.8), shock (14.4), diabetes (4.8), leukocytosis (1.1), and female sex (1.1) were significant risk factors for mortality after PUBS. However, it is possible that PUBS cases are under-reported worldwide. Conclusions: PUBS is a warning sign of a urinary tract infection, and it often follows a relatively benign clinical course. This study found that female sex, leukocytosis, shock at presentation, comorbidity with diabetes, and uremia are risk factors for mortality associated with PUBS.

Purple Urine Bag Syndrome in a Critically Ill Patient: Case Report

“…In the case we described, aggressive treatment was needed due to coexisting bacteremia and UTI with hemodynamic instability. It is noteworthy that these are actually considered risk factors for higher mortality in PUBS patients [9]. PUBS should not be ignored and further evaluation might be warranted if seen.…”

A case of purple urine bag syndrome in an elderly patient

“…The mixture of these two colors, when urine comes into contact with the catheter tube, gives the characteristic deep purple color of the urine (Figure 1). 5,6 The interaction between the plastic of the CV tube and the catheter collection bag and the indigo and indirubin pigments, as well as the high bacterial load, are fundamental criteria for the purple urine phenomenon to occur. [7][8][9] Dehydration is considered a risk factor for the onset of PUBS due to the increased concentration of indigo and indirubin in urine; the presence of alkaline urine is a contributing but not necessary factor, since several cases of PUBS have been described in the context of acid urine.…”

What is happening in that urinary catheter bag?

“…5 Constipation and use of laxatives are frequently reported among patients with PUBS, supporting the fact that a decrease in intestinal motility causes bacterial overgrowth in the intestine increasing the metabolism of tryptophan to indole and resulting in high levels of indigo (blue) and indirubin (red) pigments in the urine, responsible for the purple colour of urine. [1][2][3]6 The most common bacteria associated with PUBS are gram-negative, including E. coli, Enterococcus species, Proteus mirabilis, Morganella, and Klebsiella pneumoniae. 7 The interaction between the bag (i.e., the plastic) and pigments as well as a high bacterial load is important in precipitating PUBS.…”

“…7 The interaction between the bag (i.e., the plastic) and pigments as well as a high bacterial load is important in precipitating PUBS. 6 Risk factors for PUBS are female gender, institutionalization, dementia, constipation, long-term catheterization, CKD, dehydration, increased dietary tryptophan, alkaline urine, and the use of a Polyvinylchloride (PVC) plastic catheter. 3 Discoloration of the urine bag can appear between 2-3 months and one year of catheterization.…”