The disease starts by blockage of the hair follicles (so the hair shaft cannot grow out onto the skin surface) with resulting blockage of the sweat glands in the vicinity. Inflammation results with formation of boils (abscesses) underneath the skin. You get red swollen very painful points that will ultimately rupture with pus coming out. These heal and leave scars. They may also clump together and form bigger abscesses, or form tracts with an opening on the skin surface (draining sinuses).
The exact cause are not well understood. Genetics, male hormones (androgens), female gender (acne inversa is 3 times more common in females vs males) , obesity and smoking have been implicated.
Treatment depends on the degree and severity of the disease.
General measures include:
-Stopping smoking: can lead to improvement within several months.
-Follow a low-carb , low-dairy diet, and aim for ideal body weight.
-Wash with antiseptics or acne preparations to minimize skin bacteria. -Hydrogen peroxide solution and medical grade honey have been found helpful.
-Wear loose fitting clothing to minimize friction.
-Topical anti-acne antibiotics such as clindamycin or erythromycin in combination with benzoyl peroxide
-Short course of oral antibiotics for acute abscesses (red, hot painful discharging lump). Flucloxacillin or dicloxacillin are the most effective (unless you're allergic to penicillin)
-Prolonged courses of tetracycline or metronidazole (at least 3 months), fluoroquinolones and dapsone
-Three-month courses of clindamycin plus rifampicin may be the most effective medical treatment in severe cases.
-Metformin, usually used in treating type 2 diabetes, when taken long-term can reduce the number and severity of inflamed nodules
-Oral retinoids (vitamin A derivatives) for 6 to 12 months, especially isotretinoin, which are very effective for acne, may also help hidradenitis suppurativa
-Acitretin is not used in females of childbearing potential, but may be more effective than isotretinoin and long term remissions have been reported
-Other immunomodulatory treatments, including ciclosporin, methotrexate and azathioprine, successfully induced healing in some patients with severe disease
-Biologics (affect the immune system response), reserved for severe cases, include infliximab, adalimumab, and etanercept, may prove useful.
Surgical management includes:
Incision and drainage of abscesses – at the very painful pointing stage
Scraping out nodules and abcesses
Excision of persistent hidradenitis lumps
Radical excisional surgery
Laser hair removal and surface tissue ablation