Raw mushroom may cause flagellate dermititis

A 50-year old was recently hospitalised when he discovered a rash covering his body days after attending an Asian food festival.

However, what he presumed to be rashes were something entirely different. The bizarre scratch marks that had covered his body were due to the consumption of raw mushrooms!

While certain medications such as chemotherapy drugs can cause similar reactions on the body, doctors diagnosed him with shiitake flagellate dermatitis, a condition casued by eating raw shiitake mushrooms.

While shiitake mushrooms are widely consumed across the world and have numerous health benefits, eating them raw can trigger such reactions.

Shiitake dermitits or flagellate dermatitis (due to the whip like marks it leaves on the body) was first identified in 1977 by a Japanese scientists who saw the on several patienst after theyhad consumed mushrooms.

It turns out that the condition is caused by a toxic reaction to a molecule lentinan.

And interestingly, even partially cooked shiitakes can cause the problems.

Lentinan triggers the blood vessels to dilate and leak small amounts of inflammatory compounds beneath the skin.

The rash, which is often itchy with red spots and small blisters that form in a whip-like line on the torso, arms and legs, usually begins to appear within three days of eating the mushroom and lasts anything from ten to 21 days.

It is not thought to cause long-term damage.

Heating mushrooms to over 145c removes the risk.