When methylene blue fails: a case of methemoglobinemia induced
by azoxystrobin and propiconazole managed by exchange transfusion

Dublin Core

Title

When methylene blue fails: a case of methemoglobinemia induced
by azoxystrobin and propiconazole managed by exchange transfusion

Subject

(MeSH): azoxystrobin, Exchange transfusion, whole blood, Methemoglobinemia, Methylene blue,
Propiconazole

Description

Abstract
Background Methemoglobinemia is a potentially life-threatening condition resulting from the oxidation of
hemoglobin’s iron moiety from ferrous (Fe2+) to ferric (Fe3+). Clinical features include cyanosis unresponsive to oxygen
therapy, chocolate-colored blood, and a marked saturation gap between pulse oximetry and arterial blood gas.
Methylene blue remains the cornerstone of treatment; however, in rare instances, patients may exhibit refractory
responses necessitating advanced interventions. Literature documenting methemoglobinemia due to fungicides like
azoxystrobin and propiconazole remains scarce.
Case presentation A young female presented with altered sensorium, shock, and hypoxia following the ingestion of
a fungicide containing azoxystrobin and propiconazole. Despite a PaO2 of 400 mmHg on ABG, pulse oximetry showed
83% oxygen saturation, raising suspicion of dyshemoglobinemia. Methemoglobin levels were elevated at 80.7%. She
was treated with intravenous methylene blue. While an initial decline in methemoglobin levels to 4% was observed,
relapse occurred within 12 h. On day three, therapeutic red blood cell exchange transfusion was performed resulting
in a reduction of methemoglobin levels to 14.2%. Despite aggressive measures, she succumbed to refractory shock
on day five of admission.
Conclusion This report presents likely the first documented case of fatal methemoglobinemia due to ingestion
of azoxystrobin and propiconazole—a combination fungicide widely used in agriculture. The case highlights
the limitations of standard therapies like methylene blue in severe poisoning and underscores the need for early
consideration of exchange transfusion. With the increasing use of such agents in rural communities, clinicians must
maintain vigilance for unusual toxicities and ensure timely escalation in refractory cases.
Keywords (MeSH): azoxystrobin, Exchange transfusion, whole blood, Methemoglobinemia, Methylene blue,
Propiconazole

Creator

Rajat Goyal1*, Rushabh Bora1

, Anand Jain1

and Gopal Krishana Bohra1,2*

Date

2025

Contributor

Peri Irawan

Format

pdf

Language

english

Type

text

Files

Citation

Rajat Goyal1*, Rushabh Bora1 , Anand Jain1 and Gopal Krishana Bohra1,2*, “When methylene blue fails: a case of methemoglobinemia induced
by azoxystrobin and propiconazole managed by exchange transfusion,” Repository Horizon University Indonesia, accessed April 22, 2026, https://repository.horizon.ac.id/items/show/13265.