title: Extrapyramidal manifestations complicating organophosphorus insecticide poisoning.
abstract: Six patients who developed extrapyramidal manifestations following poisoning with the organophosphorus (OP) insecticide fenthion are reported. The extrapyramidal features, in order of frequency, were dystonia, rest tremor, cog-wheel rigidity, and choreo-athetosis. The delay in onset of these signs, following poisoning, varied from 4 to 40 days, and they disappeared spontaneously in about 1 to 4 weeks in those who survived. The human extrapyramidal system is rich in cholinergic neurons and acetylcholinesterase (AChE). Inhibition of AChE by fenthion, which has ready access to central neurons on account of its lipid solubility, is postulated as the mechanism underlying the extrapyramidal manifestations.
authors.affiliation: Department of Medicine, Faculty of Medicine, University of Peradeniya, Sri Lanka.
authors.forename: N
authors.initials: N
authors.lastname: Senanayake
authors.forename: P S
authors.initials: PS
authors.lastname: Sanmuganathan
mesh_terms: D000328:Adult; D002819:Chorea / Q000139:chemically induced; D004421:Dystonia / Q000139:chemically induced; D005116:Extrapyramidal Tracts / Q000187:drug effects*; D005260:Female; D005284:Fenthion / Q000506:poisoning*; D006801:Humans; D007306:Insecticides / Q000506:poisoning*; D008297:Male; D008875:Middle Aged; D014202:Tremor / Q000139:chemically induced
chemical_list: D007306:Insecticides; D005284:Fenthion