Chronic Neuropsychiatric Sequelae and Limitations of Cholinesterase Monitoring in Organophosphate Poisoning

Long‑Term Neuropsychiatric Effects

Persistent neurobehavioral disturbances—including cognitive deficits, memory impairment, attention problems, and mood disorders—can develop after either acute high‑dose or chronic low‑level organophosphate exposure and may last for months to years, representing potentially permanent neurological injury. 4

Red blood cell cholinesterase activity below 50 % of normal confirms significant exposure, but normal or mildly reduced levels do not reliably reflect clinical severity; therefore, cholinesterase values should not be used to guide the urgency of antidotal therapy. 4
Cholinesterase concentrations provide no predictive information regarding the risk of developing intermediate syndrome (proximal muscle weakness 24–96 h post‑exposure) or organophosphate‑induced delayed polyneuropathy (1–3 weeks post‑exposure). Consequently, clinicians must rely on clinical monitoring rather than laboratory levels to anticipate these complications. 4