Here is an excerpt from the article, ‘Hidradenitis suppurativa (HS), also known as acne inversa, is a chronic inflammatory condition that causes painful cysts, or abscesses, to develop under the skin in areas such as the armpits and groin. HS cysts often break open, releasing a foul-smelling liquid, and then heal —repeatedly. Some people also develop tunnel-like tracts under the skin connecting cysts to one another.’