Green urine secondary to methylene blue

A Curious Case of Methemoglobinemia Complicating a Pediatric Live Donor Liver Transplantation Surgery

BACKGROUND

Pediatric live donor liver transplantation (LDLT) surgery is by itself a complicated surgery. Added to the difficulty in the operative technique are the complex preoperative work-up, optimization, and postoperative treatment. Intraoperative events and immediate postoperative recovery are important in graft function and the patient's overall recovery. Intraoperative greenish-blue urine and hypoxia are seldom seen during this period in the case of LDLT. Knowing the differential diagnosis and treatment are of predominant importance.

METHODS

A case of decompensated chronic liver disease due to Wilson's disease underwent routine LDLT. Here we describe an uncommon complication, methemoglobinemia, which complicated this patient's recovery. The case is presented for the condition's rarity and the confusing clinical picture it produced.

RESULTS

Observations of greenish-blue urine, ascites, serum, gastric aspirate, bile, maroon or brown-colored blood, and hypoxia with normal PaO₂ were made in this case. Timely diagnosis of suspected drug-induced methemoglobinemia and treatment, which led to the uneventful recovery of the patient, are explained.

CONCLUSION

Even though methemoglobinemia does not have a direct graft effect, it can affect the graft oxygen perfusion and the overall oxygenation of the postoperative patient, causing adverse impacts if not detected and treated promptly. No such association of methemoglobinemia with Wilson's disease or during transplantation has been reported in the literature so far.

Methylene blue and ifosfamide-induced encephalopathy: Myth or reality?

BACKGROUND

Ifosfamide-induced encephalopathy (IIE) is a rare and serious adverse reaction. Thus far, no standard medication has been documentedto be efficient in the reversal of IIE, and while ifosfamide infusion interruption and hydration are recommended, methylene blue (MB) administration remains controversial.

METHODS

We retrospectively reviewed medical records to assess cases with IIE after ifosfamide infusion. We included all patients having received an ifosfamide infusion during their hospitalization in the medical oncology unit of the National Institute of Oncology in Rabat, Morocco, between September 2016 and September 2017. We subsequently conducted a literature review to determine the role of MB in IIE by searching PubMed using the terms "Methylene Blue" and "Ifosfamide".

RESULTS

A total of 88 patients received ifosfamide, and four patients had IIE. Ifosfamide infusion was stopped immediately after the IIE occurrence, and patients underwent renal function correction with hydration. All patients received MB infusion, and three patients had an improvement of their neurological status. As regards the literature review, 34 articles were reviewed and 16 items were included in the review. Overall, 38 (65.5%) patients received MB infusion and 28 (75.6%) patients responded favorably to the treatment.

CONCLUSIONS

Methylene blue can be used as a treatment for IIE owing to the severity of the IIE as well as absence of standard medication. Nonetheless, side effects such as serotonergic syndrome should be investigated. More broadly, prospective studies and controlled trials are needed to explore the contribution of MB in IIE management and encourage its use.

Green urine: A bezoar effect

The green color in urine may suggest the presence of a severe pathology needing treatment. Many different potential causes of green urine have previously been reported. In our case, after ruling out other potential causes of green urine, it was suggested that the surgical manipulation of the paralytic ileum might have induced the reabsorption of the methylene blue which had been retained in the bowel (bezoar effect), even 96 hours after the nasogastric administration.

CONCLUSIONS

The staff should keep in mind this possible effect due to methylene blue to recognize early and avoid unnecessary laboratory tests.

AUTHORS SUMMARY

This case report illustrates the significance of urine discoloration, sometimes indicate the presence of a systemic disorder and some rare cases, this phenomenon has no pathologic effects. To our knowledge, this is the first case report of a green urine by drug bezoar due methylene blue in children.