The Poison Review

Acute Selenium Toxicity Associated with a Dietary Supplement. MacFarquhar JK et al. Arch Intern Med 8 Feb 2010;170:256-261.

Abstract

Just 5 days ago in a previous post, I wrote that selenium toxicity was a rare occurrence.  Then I came upon this excellent paper, which details a public health investigation of 201 cases of selenium poisoning — spread over 10 different states — caused by a misformulated dietary supplement containing 200 times the intended concentration of selenium.  Common symptoms were diarrhea, fatigue, hair loss, joint pain, nail changes, and nausea.  Fever occurred in 21% of those affected.  Some symptoms — hair and nail changes, fatigue, muscle and joint pain, and memory deficits — often continued for months after exposure to selenium terminated. One patient was hospitalized.

Although the authors do not name dietary supplement involved, their description of this incident is strikingly similar to that reported in this 2008 release from the Centers of Disease Control and Prevention.

Coincidentally, while I was reading this article a rerun of House M.D. was playing in the background.  It was season 6, episode 4: “Whatever it Takes”.  House is asked by the C.I.A. to consult on one of their agents who, they think, had been a victim of an assassination attempt.HiHi  His symptoms included weakness, blistering skin, and nail changes. Multiple toxicology tests had been negative.  For security reasons, neither House nor the other consultant from the Mayo Clinic could be told where in the world the agent has travelled. Diagnoses considered include alcohol pancreatitis, radiation poisoning, and Waldenström macroglobulinemia.  When a careful review of the chart reveals that the agent has spent some time in Bolivia and was fond of chestnuts, the Mayo doc thinks it’s horse chestnut poisoning — a condition caused by the toxin esculin in unprocessed chestnuts, causing GI symptoms and occasionally paralysis.  I was convinced it was radiation.

Of course, neither myself nor the immunologist from the Mayo were any match for House M.D.  He quickly figured out that the agent was not in Bolivia but in Brazil, and actually consumed massive quantities of brazil nuts, which are extremely rich in selenium. It was extremely embarrassing that I missed the diagnosis even when the answer was literally in front of my face.

For a more complete summary of this episode of House, click here.