What is Different?
Unlike acne, which involves the sebaceous glands, Hidradenitis Suppurativa involves a different set of glands – the apocrine glands. Apocrine glands are located in the groin area and under the arms and the nipples and these glands can also become blocked. Perspiration is the culprit, much like it is with acne, but something else that can happen to the apocrine glands is that they sometimes do not develop completely. When materials become trapped inside these glands and cannot get outside the body they end up being forced out into the tissues that surround the blocked glands. The end result is a painful infection and inflammation surrounding the area of infection that sometimes causes lesions to appear on the surface of the skin.
Besides excessive perspiration, which is common in this area, there are other situations that can cause irritation in the groin area and trigger this condition. Clothing that is too tight and that constantly rubs against the skin is one culprit, but some laundry detergents can also irritate the skin. If you've got trouble in this area, try using a different detergent or even a different body soap to see if the problem goes away.
When to See a Doctor
If the problem persists and especially if the lesions are present on the genital organs, it's probably time to see a doctor. Unfortunately, genital acne (or Hidradenitis Suppurativa) is sometimes something more serious. The lesions can actually be a symptom of a sexually-transmitted disease such as genital herpes or warts and have nothing at all to do with blocked glands. Yes, this visit will likely be uncomfortable and even embarrassing, but it's absolutely necessary to get the right diagnosis. That's the only way you'll be able to make this bad situation better.
When the diagnosis is Hidradenitis Suppurativa, it's easier to treat if it's a mild case. If so, then switch to wearing clothing that doesn't fit quite so snugly. And just as with acne, you'll want to keep the affected areas free of bacteria so cleanse with an antiseptic, or hydrogen or benzoyl peroxide solution. If the lesions have a discharge or are painful, they might have an infection that requires antibiotics. Extreme lesions may even need to be sliced open and drained, but this is only recommended for very severe situations.