Indoxyl sulphate and the purple urine bag syndrome: a case report

Violet discoloration of urine: A case report and a literature review

BACKGROUND

Purple Urine Bag Syndrome (PUBS) is an uncommon event that can be described as purple discoloration of urine due to a series of chemical reactions induced by Urinary Tract Infections (UTIs). PUBS has been reported in the past but still remains unrecognized by healthcare givers leading to misdiagnosis and inappropriate management. We report our case alongside a literature review of previously published cases.

CASE PRESENTATION

We present the first case report of Purple Urine Bag Syndrome in Jordan of a catheterized 80-year-old wheel-chaired female with a history of type 2 Diabetes Mellitus (DM), stage 5 Chronic Kidney Disease (CDK), Hypertension, and ischemic stroke. Her condition was initially misdiagnosed for hematuria but later on was correctly diagnosed with PUBS. She was treated with a course of appropriate antibiotic and by changing her urinary catheter and bag. The patient returned for a follow up visit and her problem resolved with the color of her urine in the urine bag returning back to normal.

CLINICAL DISCUSSION

PUBS is an uncommon event that occurs in association with UTIs. Such cases are mostly seen in elderly catheterized patients with other risk factors.

CONCLUSION

Purple Urine Bag Syndrome can be managed by changing urinary catheter, and by the administration of appropriate antibiotics. Such event can be easily misdiagnosed thus leading to unnecessary and consuming measures. Creating a better awareness of this condition among physicians and healthcare givers is essential for better patient outcomes.

Purple Urine Bag Syndrome: More Than Eyes Can See

BACKGROUND/AIMS

Purple urine bag syndrome (PUBS) is an uncommon clinical entity characterized by purple urine discoloration in the setting of urinary tract infections. Pa-thophysiology of PUBS has been correlated to aberrant metabolism of tryptophan. Multiple predisposing factors have been recognized, namely: female gender, advanced age, constipation, institutionalization, long-term catheter-ization, dementia and chronic kidney disease. Herein, we present a comprehensive review of all PUBS cases reported in PubMed, focusing on the predisposing factors and the microorganisms related to PUBS.

METHODS

We performed a search in PubMed database for articles referring to PUBS, published in English, French, Spanish and German from January 1978 until November 2017. The literature recruitment strategy was based on several keywords and Medical Subject Heading combination such as "purple urine bag syndrome" or PUBS or "urine discoloration". The finally selected articles were categorized into case reports/series (88 articles including 112 patients) and studies (10 articles including 134 patients). Demographical data as well as predisposing factors were recorded and further analyzed.

RESULTS

According to our findings, mean age of PUBS patients was 78.9 ± 12.3 years, 70.7% were female while 90.1% were suffering from constipation, 76.1% were in a bedridden situation, 45.1% were experiencing long-term catheterization, 42.8% had been diagnosed with dementia, 14.3% had recurrent urinary tract infections and 14.1% were chronic kidney disease patients. 91.3% of patients presenting with PUBS alkaline urine were observed while the most common microbe in urine cultures was E. coli.

CONCLUSIONS

PUBS is considered benign process in the majority of catheterized patients. Clinicians should be aware of the syndrome that may indicate serious comorbidities.

Trends in the epidemiology of purple urine bag syndrome: A systematic review

Purple urine bag syndrome (PUBS) is rarely observed in clinical practice. The present study aimed to identify the epidemiological trends in PUBS in recent decades. A search of PubMed articles published between 1980 October and 2016 August was conducted, in which 106 articles (174 cases) described PUBS. Of these cases, 58 cases were excluded: 14 cases without mention of gender, 4 cases without description of age, 37 cases without mention of white blood cell (WBC) count, shock status, fever status or description of etiology, and 3 cases without information on mortality. The remaining 116 PUBS cases were collected and analyzed in the present study. The articles were divided into three groups by publication year: 1991 to 2000, 2001 to 2010 and 2011 to 2016. The χ² test was used for statistical analysis, with P<0.05 (two-tailed) defined as the threshold for significance. Of the total enrolled cases, there were 47 men (40.5%) and 69 women (59.5%), with a mean age ± standard deviation of 75.6±12.8 years. Of these, 98 cases (84.5%) were elderly (≥65 years old). A total of 93.1% of cases had a urine pH >7 while 6.9% of cases had acidic urine (pH <7). Furthermore, although WBC count elevated progressively, the mortality rate of patients with PUBS decreased over subsequent decades. This necessitates the advancement of antibiotics and application of early goal-directed therapy. Additionally, the overall mortality rate of PUBS (1980-2016) was 6.8%, which decreased to 4.3% in the last 5 years (2011-2016). In conclusion, although PUBS has previously been considered a benign process in the majority of indwelling catheterized patients, emphasis is required on early examination and aggressive antibiotic administration.

Trends in the epidemiology of purple urine bag syndrome: A systematic review

Purple urine bag syndrome (PUBS) is rarely observed in clinical practice. The present study aimed to identify the epidemiological trends in PUBS in recent decades. A search of PubMed articles published between 1980 October and 2016 August was conducted, in which 106 articles (174 cases) described PUBS. Of these cases, 58 cases were excluded: 14 cases without mention of gender, 4 cases without description of age, 37 cases without mention of white blood cell (WBC) count, shock status, fever status or description of etiology, and 3 cases without information on mortality. The remaining 116 PUBS cases were collected and analyzed in the present study. The articles were divided into three groups by publication year: 1991 to 2000, 2001 to 2010 and 2011 to 2016. The χ² test was used for statistical analysis, with P<0.05 (two-tailed) defined as the threshold for significance. Of the total enrolled cases, there were 47 men (40.5%) and 69 women (59.5%), with a mean age ± standard deviation of 75.6±12.8 years. Of these, 98 cases (84.5%) were elderly (≥65 years old). A total of 93.1% of cases had a urine pH >7 while 6.9% of cases had acidic urine (pH <7). Furthermore, although WBC count elevated progressively, the mortality rate of patients with PUBS decreased over subsequent decades. This necessitates the advancement of antibiotics and application of early goal-directed therapy. Additionally, the overall mortality rate of PUBS (1980-2016) was 6.8%, which decreased to 4.3% in the last 5 years (2011-2016). In conclusion, although PUBS has previously been considered a benign process in the majority of indwelling catheterized patients, emphasis is required on early examination and aggressive antibiotic administration.

[Biochemical and bacteriological investigation of six cases of purple urine bag syndrome (PUBS) in a geriatric ward for dementia]

AIM

Purple urine bag syndrome is a condition in which the urinary catheter bag turns purple. A tryptophan-indigo hypothesis has been proposed as the mechanism of PUBS, in which bacterial decomposition of tryptophan in gut associated with chronic constipation, bacterial overgrowth in the urinary tract and alkaline urine causes production of indigo and discoloration. We considered that further investigation of cases was needed.

METHODS

We investigated 6 cases exhibiting PUBS (3 males and 3 females).

RESULTS

All cases had chronic constipation. Oral ingestion was impossible in one case. PUBS disappeared after antibiotic treatment (3 cases) or spontaneously (one case). Alkaline urine and indicanuria were not found in all cases that showed the disappearance of PUBS. In bacterial culture of urine during the exhibition of PUBS, Enterococcus faecalis was isolated together with Morganella morganii (3 cases) and Pseudomonas aeruginosa (one case). Single infections by Klebsiella pneumoniae or Citrobacter species were also found. After disappearance of PUBS, infected bacterial species changed but no cases showed sterile urine. Urine and blood alpha-amino-n-butyric acid levels reduced after the disappearance of PUBS whereas tryptophan levels did not show related changes. In one case, blood protein concentration increased after the spontaneous disappearance of PUBS. Indicanuria and alkalization of urine from urinary catheter bag were more intense than of fresh urine.

CONCLUSIONS

The present results generally support the 'Tryptophan-indigo hypothesis'. Furthermore, it was suggested that additional factors associated with the occurrence of PUBS are an environment that facilitates specific bacterial growth in a hospital as well as abnormal metabolism relating to alpha-amino-n-butyric acid and reduced protein synthesis in patients.