Identification of atypical calcium oxalate crystalluria following ethylene glycol ingestion.

A case of ethylene glycol poisoning was associated with heavy crystalluria unidentifiable by light microscopy. Extensive analysis utilizing scanning electron microscopy, x-ray fluorescence, and diffraction method revealed that the sediment contained calcium oxalate monohydrate in one crystallographic phase. Newest diffraction data for identification of the various forms of calcium oxalate, along with the photographs of the crystals by light and electron microscopy, are included. Fifty cases of ethylene glycol poisoning were reviewed to ascertain the most common form of calcium oxalate crystalluria. The search revealed scanty morphologic data associated with the calcium oxalate crystalluria; however, numerous forms were reported. It is concluded that calcium oxalate crystalluria following ethylene glycol ingestion may assume many forms, which should be recognized to facilitate the rapid diagnosis of ethylene glycol ingestion.