Calcium oxalate crystals found in urine in poisoning due to: (PGI June 2007)

Ans.: C (Ethylene glycol poisoning) Ethylene Glycol Poisoning Harrison 17th/291Ingestion of ethylene glycol (commonly used in antifreeze) leads to a metabolic acidosis and severe damage to the central nervous system, heart, lungs, and kidneys. The increased AG and osmolar gap are attributable to ethylene glycol and its metabolites, oxalic acid, glycolic acid, and other organic acids. Lactic acid production increases secondary to inhibition of the tricarboxylic acid cycle and altered intracellular redox state.Diagnosis is facilitated by recognizing oxalate crystals in the urine, the presence of an osmolar gap in serum, and a high-AG acidosis.If antifreeze containing a fluorescent dye is ingested, a Wood's lamp applied to the urine may be revealing.Treatment should not be delayed while awaiting measurement of ethylene glycol levels in this setting