Red Is Not Always Bad: Vin Rosé Urine in a Kidney Transplant Patient with Sickle Cell Crisis

Introduction: The most common cause of red colored urine is the presence of blood, hemoglobin or heme from a wide variety of causes that include cancer, infection, nephrolithiasis, glomerulonephritis and hemolysis. Red urine from non heme related causes is rare and can occur after beet ingestion, phenazopyridine and hydroxycobalamine. Case Description: A 35 y/o man with sickle cell disease (HbSS) and ESRD treated by living related kidney transplant in 2021 was admitted for sickle cell crisis and pain control. The patient has had multiple previous admissions for sickle cell crisis, with AKI and severe anemia requiring multiple blood transfusions with post-transfusional iron overload. He also had a history of stroke, seizures and DVT. His treatment included Tacrolimus ER, Cellcept, Prednisone, Hydroxyurea, Deferiprone, Apixaban, Pregabalin, Nifedipine and Methadone. The patient’s physical exam was remarkable for BP 136/90 and diffuse body aches. His Hb was 10.5g/dl, creatinine 0.9mg/dl at baseline, electrolytes normal, ferritin 12080 ng/ml and tacrolimus level 5.2ng/ml. The urine had red color (picture 1); the urinalysis revealed trace blood and the urine sediment showed a few epithelial cells and no RBC. Ultrasound of the native kidneys, renal transplant and bladder was unrevealing. Discussion: The typical red coloration of urine of a patient with iron overload who is treated with an iron chelator is called Vin rosé urine. This color change can be useful as a diagnostic test to confirm iron intoxication in children. The red color constitutes an iron related but non heme cause of red urine. As it is not a sign of renal pathology, a description of it is lacking in the nephrology literature. However, as urinalysis experts nephrologists should be aware of it.Figure 1: Vin rosé urine