Friday, May 11, 2007

Answer: VizD Challenge Week of 5/7/2007

*NY Emergency Medicine Exclusive*

Congratulations to Helen - she is the first person to submit the correct answer to this week's VizD. Helen is the winner of $10

To view Helen's answer, click here

This week, Dr Lewis Nelson, Director of the Toxicology Fellowship at the New York City Poison Control Center will discuss the answer to this weeks VizD

NYEM: How frequent are diethylene glycol (DEG) poisonings?

LN: The DEG poisonings that make the news are the ones that occur in epidemics. It seems that every few years an epidemic DEG poisoning occurs somewhere in the world, and they are nearly always related to the use of DEG as a diluent/solvent for a medication. The first widely recognized epidemic occurred in the US in 1937 due to its use in an antibiotic formulation (sulfanilamide). The result of this event lead to the formation of the FDA. Epidemic poisonings have occurred recently in India, Bangladesh, Nigeria, and Haiti. In Haiti DEG was used as a diluent for a liquid acetaminophen preparation, and many (over 100) children developed renal failure and some died. Many of these kids were sent to the US for hemodialysis. This last poisoning event in Panama involved a sugarless cough preparation/expectorant that was widely used by diabetic patients, accounting for the different patient demographic. The DEG was sold as glycerine (glycerol), a sweet non-sugar that is used by diabetics, and is structurally very similar to DEG. Isolated cases of DEG in the US, while not common, poisoning occurs due to the use of DEG in industry and in automotive products (e.g., brake fluid).

NYEM: What makes diethylene glycol sweet in taste?

LN: Not only is DEG sweet, but so is ethylene glycol. DEG has even been purportedly used (illegally) in low quantities to sweeten wine. The reason for the sweet taste of these glycols (which are poly-ols) is likely related to the way these chemicals interact with our "sweet" taste receptors. Realize that sugars (such as glucose, which are receptors are likely supposed to sense) are also poly-ols, so this makes conceptual sense.

NYEM: It's interesting that the creation of the FDA was based on a poisonous elixir of diethylene glycol used in sulfanilamide, yet 70 years later we are still faced with this problem?

LN: This is likely due to the lack of sophistication and regulatory controls of these other nations. If you read the recent NY Times article on the path taken by the DEG to get from China to Panama it becomes clear that nowhere along the line, including at the end, did anyone verify that the contents of the drums labeled "glycerine" actually contained this compound. Never say never when it comes to things like this, but the US regulatory system is much tighter than it is in less developed nations.

NYEM: Have you recently seen a diethylene glycol poisoning in New York City?

LN: We have, though as mentioned above, it has been isolated in nature. Most cases have originated from the drinking of automotive or hydraulic fluid. In an odd case about two years ago, a young man was intentionally poisoned (in what I recall was a "joke") by the chemical used to make artificial fog, which contained DEG. Recently, a patient presented to her primary care physician with some vague complaints. On questioning she produced a bottle of Panamanian of "expectorante" purchased on a recent trip that that country. Although she did not have renal failure, her medication contained 8% DEG.

NYEM: If you were on a desert island and were poisoned with diethylene glycol but could only give yourself one of the following treatments ethanol, fomepizol, or hemodialysis which would it be?

LN: There is no know role for ethanol or fomepizole; in fact there is some weak suggestion that these may be harmful. The lack of insight stems from the fact that the parent compound, not the metabolite, may be the toxic component. This suggests that we need to be cautious making analogies between the various toxic alcohols. Hemodialysis is the treatment of choice as it clears both the parent compound (DEG) and any metabolites. However, if I was on a desert island I would go for the ethanol! (the thought of putting those catheters in my groin is pretty intimidating)

NYEM: Do you recommend a toxicology fellowship for Emergency Medicine Residents?

LN: Only for the motivated few, but this is a whole different discussion.

NYEM: What made you get so interested in toxicology?

LN: I understood pharmacology and physiology in med school.

NYEM: Do you have a favorite historical toxicologist?

LN: Lewis Goldfrank, although he may take offense to being labeled as historically important.

NYEM: How many editions are there of Goldfrank's Toxicology?

LN: Edition 8 is out, working on 9 already (only 4 years to go)

NYEM Are you working on any other books?

LN: Always! I, along with another like minded colleague and an ethnobotanist at the New York Botanical Garden, recently published a book on the medical aspects of poisonous plants. Its called the "Handbook of Poisonous and Injurious Plants", it has great pictures. I may have another book or two up my sleeve.

NYEM: Thank you Dr Nelson

LN: Anytime!

VizD is a weekly contest of an interesting or pathognomonic image from emergency medicine. Its goal is to integrate learning into a fun and relaxed environment. All images are original and are posted with the consent of the patient. For more information please refer to the following link.

1 comment:

Adam said...

Helen,
Congratulations - please send an email to nyemergencymedicine@gmail.com to arrange receipt of your prize