Atypical Presentation of Organophosphorus Poisoning Without Exposure History in a Child: Diagnostic Value of Electrophysiology

We highlight an atypical case of pediatric organophosphorus poisoning diagnosed without suggestive history, emphasizing the role of clinical judgement, electrophysiological studies, and biochemical investigations. A 13-year-old girl presented with recurrent episodes of neuromuscular weakness, respiratory distress, bronchospasm, and profuse secretions, each followed by near-complete recovery. Routine neuroimaging and cerebrospinal fluid analyses were unremarkable. Absence of exposure history delayed diagnosis. Recurrence of cholinergic features and intermediate-phase weakness prompted evaluation. Nerve conduction studies revealed repetitive muscle action potentials, and red blood cell cholinesterase was markedly reduced. Treatment with atropine and pralidoxime led to improvement and recovery. Organophosphorus (OP) poisoning should be considered in children with unexplained recurrent neuromuscular weakness and autonomic symptoms, even without exposure history. Electrophysiology and cholinesterase assays are valuable diagnostic tools in such scenarios.