Lambda-cyhalothrin ingestion: an infrequent yet concerning presentation of pyrethroid poisoning

Area of Science:

• Toxicology
• Emergency Medicine
• Clinical Case Study

Background:

• Lambda-cyhalothrin is a common type II pyrethroid pesticide with potential for severe human toxicity.
• Organophosphate poisoning is frequently reported in Nepal, often presenting with overlapping symptoms to other pesticide classes.
• Accurate identification of ingested pesticides is critical for effective emergency management.

Observation:

• A 40-year-old female presented with symptoms of confusion, abdominal pain, nausea, and vomiting after intentional ingestion of an unknown pesticide.
• The patient had a history of alcohol intoxication and a negative atropine challenge test.
• Subsequent identification revealed the ingested substance was lambda-cyhalothrin; the patient improved with supportive care.

Findings:

• Clinical features of lambda-cyhalothrin poisoning can resemble organophosphate poisoning, leading to potential misdiagnosis.
• A negative atropine challenge test, in the absence of cholinergic features, suggests non-organophosphate poisoning.
• Comprehensive clinical evaluation is essential when the exact nature of an ingested pesticide is initially unknown.

Implications:

• Differentiating pyrethroid from organophosphate poisoning through clinical assessment and diagnostic tests like the atropine challenge is vital.
• Accurate diagnosis prevents inappropriate treatments, such as unnecessary atropine administration in non-organophosphate poisonings.
• This case highlights the importance of a systematic approach to managing unknown pesticide ingestions to ensure optimal patient outcomes.