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Case Reports
. 2025 Jan 10;17(1):e77235.
doi: 10.7759/cureus.77235. eCollection 2025 Jan.

A Curious Case of Purple Chromaturia

Richa Dhakal  1 , George S Zacharia  1 , Nismat Javed  1 , Puja K C  1 , Misbahuddin Khaja  2
Affiliations
Case Reports

A Curious Case of Purple Chromaturia

Richa Dhakal et al. Cureus. .

Abstract

Hydroxocobalamin, an antidote for cyanide toxicity, is known for its safety and efficacy. A notable side effect is dark red to purple chromaturia, sometimes mimicking hematuria. We report the case of a middle-aged female exposed to smoke inhalation following a house fire, who was treated on-site by emergency medical services with oxygenation and intravenous hydroxocobalamin and developed purple urine shortly after admission. Hematuria, hemolysis, rhabdomyolysis, and renal impairment were excluded with appropriate workup. The discoloration resolved spontaneously over five weeks without intervention, consistent with hydroxocobalamin-induced chromaturia. While benign and self-limiting, this phenomenon may cause diagnostic confusion and patient concern. Awareness of this side effect can prevent unnecessary investigations and reassure patients about its transient nature.

Keywords: chromaturia; cyanide toxicity; hydroxocobalamin; management; purple urine.

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Conflict of interest statement

Human subjects: Consent for treatment and open access publication was obtained or waived by all participants in this study. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work.

Figures

Figure 1
Figure 1. Portable chest X-ray showing atelectatic changes
Figure 2
Figure 2. Indwelling catheter showing purple to purple-red urine
See this image and copyright information in PMC

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References

    1. Cyanide intoxication as part of smoke inhalation--a review on diagnosis and treatment from the emergency perspective. Lawson-Smith P, Jansen EC, Hyldegaard O. Scand J Trauma Resusc Emerg Med. 2011;19:14. - PMC - PubMed
    1. U.S. Department of Health and Human Services. Hydroxocobalamin (Cyanokit) as a cyanide antidote. Accessed. [ Nov; 2024 ]. 2024. https://chemm.hhs.gov/countermeasure_hydroxocobalamin.htm#adv https://chemm.hhs.gov/countermeasure_hydroxocobalamin.htm#adv
    1. Hall JE. Guyton and Hall Textbook of Medical Physiology. 13th ed. Philadelphia, PA: Elsevier; 2016. The liver as an organ; p. 885.
    1. Differentials of abnormal urine color: a review. Singh A, Agrawal P, Singh A, Singh O. https://www.researchgate.net/publication/267327377_Differentials_of_abno... Ann Appl Biosci. 2014;1:0–25.
    1. Urinalysis in the diagnosis of kidney disease. [ Jan; 2025 ]. 2024. https://www.uptodate.com/contents/urinalysis-in-the-diagnosis-of-kidney-... https://www.uptodate.com/contents/urinalysis-in-the-diagnosis-of-kidney-...

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