From: sbharris@ix.netcom.com(Steven B. Harris)
Newsgroups: sci.med
Subject: Re: pellagra vs pellagra sine pellagra
Date: 19 May 1998 09:30:40 GMT

In <355b3eaa.1600296@news.tvd.be> david.bulte@tvd.be (David Bulté)
writes:

>Does anybody know, why niasine deficiency is called pellagra, and why
>in turn riboflazine deficiency is called pellagara sine pellagra? I am
>asking this for my sister, who is a medical student. She could not
>find the answer in one of her books.
>
>Thanks for helping her out
>
>Kristien Hens


   The word pellagra means "rough skin".  When skin is subjected to
mechanical wear and tear and can't repair itself well, it acts like a
burn which cannot heal.  You get an inflammatory response, redness,
cracking into deeper layers along stress lines, but no new tissues from
dividing fibroblasts.  In niacin deficiency the outer layers of the
skin don't come off very well in these areas, and these dead layers act
as a sort of protectant for the areas under them, which remains cracked
and reddened.  That outer layer is the part that feels rough.  In
riboflavin deficiency the electron transport system in mitochondria
still doesn't work and the cells still can't respire aerobically, and
you get all the same problems, but for some reason I don't understand,
the outer layers of the skin slough more readily, so all the underlying
damage and failure of repair is more easily seen.  Thus, pellagra
without the roughness- pellagra sine pellagra.