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A Tale of Two Urines

A Tale of Two Urines

  • The Tale of Two Urines

  • Polly, 8-years-old, is brought in acutely because she told her mother that her urine was “red.”

  • History/PE:Polly has always been healthy; no urinary tract infections/disease in the past; no renal disease in either Polly or the family; no trauma, no menarche.

  • No new or unusual foods introduced recently; Polly has not been given any medications in the last year or so.

  • Urine is collected and is definitely reddish-pink.

  • But, the dipstick is negative for hematuria.

  • Microscopic examination of the urine specimen is now required.

  • Urate crystals are present in every field.

  • Likely diagnosis was urate-induced pink coloration of the urine. More detailed history found that Polly's diet was very rich in purines-sardines, roasted nuts, fried foods.

  • Conditions that simulate hematuria include dehydration, pigments, medications.

  • Red urine can be caused by numerous substances including anthocyanin, azo dyes, beets, chloroquine, rifampin, rhodamie B, sulfasalazine, urates.

  • A 16-year-old male presents with green urine. He was asymptomatic and otherwise entirely well; no history of gall bladder disease.

  • The urine's green hue is unmistakable.

  • Detailed family history, noncontributory; physical exam, totally normal.

  • On closer examination, the young man's tongue also is green.

  • Green urine and green tongue appear to be caused by ingestion of Clorets gum for the past several days. FD&C blue #1 is the culprit ingredient.

  • Differential diagnosis of green urine: Iodochlorhydroxyquin-induced, myelo-optic neuropathy, Pseudomonas bacteremia, bile pigment, amitriptyline HCl, methocarbamol, metoclopramide (not an exhaustive list).

  • Green urine also is caused by dyes: indigo, carmine, phenol, methylene blue.

Over my years in working with residents, I have always impressed on them that we are all very much medical detectives. It is nice to use dermatology clues, but they are not always present.

So, I always emphasize the holistic approach – we must look at urine and stool specimens, blood smears,  microbiology plates… whatever we might have to  assist us as we try to solve “mystery cases.”

In recent times, however, performing our own lab tests is not allowed. I, being “old school,” have always had a microscope available in the office which allows me to provide some quick answers/additional clues. It is also advantageous to have the lab close by and to hav friendly lab techs who will invite you to come have a look at what they are seeing. This, I suggest, is the true art of medicine and reinforces learning. I often tell residents that “I am a PGY-XX” and that I will always be a student.

This year I announce that “I am a PGY- 43 11/12” as I ignore the eye rolling and the “under the breath” snickering.

And that brings us to today’s two medical mysteries as I invite you and a virtual resident to  reenact your version of Sherlock Holmes/Columbo.


Resources/Additional reading (alphabetical order)

Gupta D, Gupta R. Green urine. ScientificWorldJOURNAL.  2011;11: 1101–1102.

Koratala A, Leghrouz M. Green urine. Clin Case Rep. 2017;8:549-550. doi: 10.1002/ccr3.891. eCollection 2017 Apr.

La Manna A, Polito C, Marte A, et al. Hyperuricosuria in children: clinical presentation and natural history. Pediatrics. 2001; 107:

Prakash S, Saini S, Mullick P, Pawar M. Green urine: A cause for concern? J Anaesthesiol Clin Pharmacol. 2017;33:128-130. doi: 10.4103/0970-9185.202190.

Raymond JR, Yarger WE. Abnormal urine color: differential diagnosis. South Med J. 1988;81:837-41.


I like happy conclusions for patients. 2 very interesting and fun cases. The clorets dx was great and funny.
The practice of medicine these days is so serious and we forget about the power of humor and laughter in dealing with patients.
jdbritton, md, mph

Anonymous @

Thank you, but unfortunately I cannot view all the slides. I don't know what is the problem. Can anybody help please?

Babak @

Interesting case study, Doctor.

Helpful, interesting, fun, well put together.

This may sometime save some patient a few hundred dollars in unnecessary testing :)

Thank you.

Elden @

Interesting cases for medical students, residents, and experienced doctors!

Anonymous @

Thank you for your encouragement. My cancer (Neuroendocrine) has reached the point that after 8 years of stage 4 disease with some miraculous interventions I am now in the terminal phase. Doing these cases has been a very positive outlet for me. Grace Halsey's editing has made these better, too. It is my hope to do a few more cases before I reach the finish line.

Jon Schneider
Author and now a PGY-44

Jonathan @

What a great article! Reminds us that we should always be the good detectives our medical schools trained us to be! I enjoyed the review, thank you.

Natalie @


Mary Lou @

Best medical article I have read in along time

Alan @

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