Severe methemoglobinemia due to insecticide poisoning

Methemoglobinemia Following Indoxacarb Ingestion: A Unique Toxicological Presentation

Indoxacarb, an oxadiazine insecticide, is known for its selective lethality by blocking neuronal voltage-dependent sodium channels. While primarily developed to target insect populations resistant to other pesticides, its toxicity in humans remains poorly understood. We present a case of methemoglobinemia resulting from indoxacarb ingestion, a rare manifestation of its toxic effects. A 38-year-old farmer attempted suicide by ingesting the insecticide, leading to cyanosis, hypoxemia, and characteristic arterial blood gas findings indicative of methemoglobinemia. Prompt diagnosis was challenging due to the absence of specific tests, necessitating clinical suspicion. Treatment with methylene blue and supportive therapy resulted in significant clinical improvement, highlighting the importance of early intervention in managing indoxacarb poisoning. This case underscores the need for increased awareness among healthcare providers regarding the potential toxic effects of indoxacarb. It emphasizes the importance of prompt recognition and treatment of methemoglobinemia in pesticide-related poisonings. Further research is warranted to elucidate the mechanisms underlying indoxacarb toxicity in humans and to optimize treatment strategies for affected individuals.

Acquired methemoglobinemia induced by indoxacarb poisoning: a case report

Indoxacarb, a large-spectrum non-organophosphorus oxadiazine insecticide, is broadly used in farming whose mechanism of action is the blockage of voltage-gated sodium channels of insects. There is restricted data on human poisoning. We report a case of an 18-year-old male patient without comorbidities presented with unconsciousness and cyanosis after the intentional ingestion of indoxacarb in a suicide attempt. Methemoglobinemia was clinically suspected and was successfully treated after methylene blue injection, associated with supportive and symptomatic management. This case emphasizes the importance of considering methemoglobinemia after indoxacarb ingestion in addition to its early recognition and timely injection of methylene blue which led to complete recovery without sequelae.

A Rare Presentation of Imidacloprid Poisoning

Acute poisoning with pesticides and insecticides can sometimes result in unexpected clinical manifestations. Awareness regarding all possible signs and symptoms of poisoning with these compounds can help in timely diagnosis and treatment. Deliberate ingestion of imidacloprid, a neonicotinoid insecticide, despite being minimally lethal to humans, proved to be life-threatening to a 14-year-old boy. A prompt diagnosis of methemoglobinemia followed by the administration of methylene blue led to successful recovery.

Toxin-Induced Methemoglobinemia With Kidney Injury and Hypoxic Brain Injury in a Case of Pesticide Poisoning: A Case Report

In many developing nations like India, the majority of the labor force comprises farmers. Therefore, there is a raised frequency of farmer suicides using pesticides. Toxin-induced methemoglobinemia is otherwise called toxic methemoglobinemia. It is a hematologic disorder attributed to exposure to toxic oxidizing agents and is most commonly seen in cases of poisoning. Methemoglobinemia is a condition in which there is an altered state of hemoglobin, resulting in reduced oxygen delivery to tissues. This case report represents a case of methemoglobinemia with acute kidney injury and hypoxic brain injury seen in a 23-year-old male patient. He was a farmer by occupation and was admitted due to ingestion of a pesticide named HUNT with suicidal intentions. He has had no previous history of psychiatric or neurologic disorders. The patient initially presented with a pulse rate of 110/min and room air saturation of 98% when he was brought to the casualty out patient department (OPD). Unfortunately, it worsened over the next 24 h, after which there was a sudden drop in SpO2 to 78% with oxygen support. Upon further examination and assessment, he was diagnosed with methemoglobinemia, leading to complications such as acute kidney failure and cerebral edema. He was then treated with hemodialysis, methylene blue, and ascorbic acid with viable improvement. This led to his complete recovery after eight days of treatment and support.

A Rare Cause of Methemoglobinemia: How Safe are So-called Biopesticide?

With increasing awareness of "greener" environment, market is flooded with biopesticide. Natural insecticides can be chemical, mineral, or biological. We report an unusual case of methemoglobinemia after deliberate ingestion of an insecticide containing extract of pine oil and azadirachtin oil, Ti oil, and kerosene. On literature search, no such case report has been documented so far. How to cite this article: Gupta P, Verma PK. A Rare Cause of Methemoglobinemia: How Safe are So-called Biopesticide? Indian J Crit Care Med 2020;24(3):208-209.

Role of Automated Therapeutic Red Cell Exchange in the Setting of Acute Methemoglobinemia: Our Experience

Methemoglobinemia, an altered state of hemoglobin resulting in impaired oxygen delivery to the tissues can be congenital or following exposure/ingestion of various oxidant drugs or toxins. One of the earliest signs of methemoglobinemia is generalized cyanosis not improved on oxygen supplementation and presence of normal PO₂ on acid blood-gas analysis. Here, we report two cases of acquired methemoglobinemia following poisoning and our experience of managing them with automated therapeutic red cell exchange.

CPB1 of Aedes aegypti interacts with DENV2 E protein and regulates intracellular viral accumulation and release from midgut cells

Aedes aegypti is a principal vector responsible for the transmission of dengue viruses (DENV). To date, vector control remains the key option for dengue disease management. To develop new vector control strategies, a more comprehensive understanding of the biological interactions between DENV and Ae. aegypti is required. In this study, a cDNA library derived from the midgut of female adult Ae. aegypti was used in yeast two-hybrid (Y2H) screenings against DENV2 envelope (E) protein. Among the many interacting proteins identified, carboxypeptidase B1 (CPB1) was selected, and its biological interaction with E protein in Ae. aegypti primary midgut cells was further validated. Our double immunofluorescent assay showed that CPB1-E interaction occurred in the endoplasmic reticulum (ER) of the Ae. aegypti primary midgut cells. Overexpression of CPB1 in mosquito cells resulted in intracellular DENV2 genomic RNA or virus particle accumulation, with a lower amount of virus release. Therefore, we postulated that in Ae. aegypti midgut cells, CPB1 binds to the E protein deposited on the ER intraluminal membranes and inhibits DENV2 RNA encapsulation, thus inhibiting budding from the ER, and may interfere with immature virus transportation to the trans-Golgi network.