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Updated: May 26, 2026

Assessing Urinary Tract Junction Obstruction Defects by Methylene Blue Dye Injection
Published on: October 12, 2017
Abnormal urine color
1Department of Emergency Medicine, Staten Island University Hospital, Staten Island, New York 10305, USA. ryanaycock@gmail.com
Abstract:
A change in urine color can be distressing for patients and physicians alike. Many of the causes of abnormal urine color are benign effects of medications and foods; however, a change in urine color may be a sign of an underlying pathological condition. The good news is that in many cases the diagnosis can be determined from a thorough history and urinalysis. This article presents many of the conditions physicians may encounter and will help them form a narrow differential diagnosis and treatment plan.
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