Naked Science Forum

Life Sciences => Physiology & Medicine => Topic started by: thedoc on 25/05/2016 15:50:02

Title: What causes black patches on the skin?
Post by: thedoc on 25/05/2016 15:50:02

asked the Naked Scientists:
   I am listening to 702 and hear Chris (naked scientist)  is helping people with different kinds of problems and I really need help I want to know what causes black patches around the waist, between thighs, cheeks around eyes and surrounding the mouth, the patches are not itchy, not painful, you just see them growing without feeling anything, no rashes just changing of skin colour to dark black,  I am 44 years.
What do you think?

Title: Re: What causes black patches on the skin?
Post by: chris on 25/05/2016 19:56:40

Do you have white, or black skin naturally?

Title: Re: What causes black patches on the skin?
Post by: RD on 26/05/2016 00:47:47

A condition called "acanthosis nigricans (https://www.google.com/search?site=&tbm=isch&source=hp&biw=1280&bih=677&q=acanthosis+nigricans&btnG=Search+by+image)" causes patches of dark skin, ( sometimes dark as soot ).
http://www.dermnetnz.org/systemic/acanthosis-nigricans.html

Title: Re: What causes black patches on the skin?
Post by: evan_au on 26/05/2016 10:56:52

Much less likely is the "Black Plague" that wreaked havoc throughout Europe in the Middle Ages.

But there are still a few cases every year in the USA...
https://en.wikipedia.org/wiki/Bubonic_plague#Signs_and_symptoms

These black patches are associated with swollen lymph glands.
These days it can be treated easily with antibiotics.