A worker exposed to organophosphate insecticide presents with pinpoint pupils, bradycardia, and excessive secretions. After initial treatment, serial measurements of which laboratory parameter best track recovery from the poisoning?

• A Serum alanine aminotransferase activity
• B Erythrocyte acetylcholinesterase activity ✓
• C Serum gamma-glutamyl transferase activity
• D Plasma aldolase activity

Explanation

Organophosphates inhibit acetylcholinesterase irreversibly by phosphorylating its serine active site, producing accumulation of acetylcholine and the cholinergic crisis described. Erythrocyte acetylcholinesterase reflects the neuronal enzyme and correlates with symptom severity, so serial values monitor recovery, which may take weeks as new enzyme is synthesised. Plasma (pseudocholinesterase) recovers faster and reflects recent exposure, while ALT, GGT, and aldolase are markers of liver or muscle injury and play no role here.

Reference: Katzung's Basic and Clinical Pharmacology, 16th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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