Hidradenitis Suppurativa (Acne Inversa)

Hidradenitis suppurativa is a condition where multiple abscesses form under the armpits and often in the groin area.

Hidradenitis suppurativa is a chronic inflammatory skin disease that affects hair follicles in the armpits and groin but occasionally may involve the buttocks and scalp.

• The lesions often first appear in puberty but may begin at any age. The lesions appear as tender, red abscesses that may drain.
• Severe hidradenitis suppurativa can involve more significant areas of skin, producing multiple draining sinuses with scarring.

Although as many as 40% of patients with HS have a family history of this condition, the precise genetic defect is poorly understood. Health researchers have found a defect in the gamma-secretase Notch signaling pathway in a few patients, but this basic cell regulatory pathway appears mutated only in a minority of those with HS. Patients with HS tend to be obese and frequently smoke. There is microscopic evidence that inflammation in the hair follicles is the seat of the problem and not the apocrine sweat glands as was originally believed. Ultimately, the precise cause is unknown.

The risk factors for hidradenitis suppurativa include:

• Obesity
• High cholesterol (Hyperlipidemia)
• Diabetes
• Acne
• Arthritis
• Inflammatory bowel disease
• Polycystic ovarian syndrome
• Depression

Symptoms and signs of hidradenitis suppurativa include:

• Patients with the skin condition develop recurrent boil-like lesions in their armpits and groin (areas with sweat glands) that appear as painful, small lumps.
• The bumps or sores may begin to leak and drain pus.
• There are blackheads in areas of affected skin.
• Individual lesions may join to produce long draining sinus tracts or tunnels that are tender and continually produce foul-smelling pus drainage.
• When healing occurs, it often leaves multiple areas of unsightly scarring.
• Less commonly, lesions can involve the lower abdomen and the tissues under the breasts.

Dermatologists are well equipped to care for patients with this condition although they may require surgical support if removal of significant portions of the armpits and groin are required for control.

A patient with recurrent abscesses in the armpit, groin, or buttocks may well have hidradenitis suppurativa (HS). The condition may vary from mild to quite severe cases.

Infections produced by bacteria or fungi need to be excluded because they often are quite curable with antibiotics, whereas HS is not. Doctors may check patients for immune deficiency diseases.

Since this is a chronic recurrent condition, many treatment options depend on the severity.

• For a mild disease with infrequent lesions, doctors recommend that patients use topical antibiotics, lose weight, stop smoking, and avoid tight underwear.
• For more severe involvement, adding an oral antibiotic, such as doxycycline may be necessary.

Since this is a chronic and challenging condition, doctors have proposed various other options, but most lack compelling evidence of efficacy. Physicians recommend finasteride (Proscar), a drug used to treat benign prostatic hypertrophy, as an option to treat HS in certain patients with resistant disease. Given its cost and safety profile, it seems a reasonable alternative for patients who are unresponsive to conventional measures. There is anecdotal evidence that an oral retinoid, acitretin, can be of benefit.

The FDA recently approved a new injectable medication, adalimumab (Humira), for moderate to severe HS. Humira is one of a class of medications called tumor necrosis factor inhibitors, which intercept a chemical messenger of inflammation.

Occasionally, it may be necessary to resort to surgery to control and treat HS. It may be necessary for physicians to surgically open persistent chronic fistulous tracts to facilitate healing. Rarely, extensive removal of significant portions of axillary (armpit) or inguinal tissue may be required, followed by skin grafting.

Since HS is a chronic, recurrent condition, a cure is unlikely, but with the advent of new drugs that are effective modulators of inflammation, it is reasonable to expect safe and effective control of this difficult condition.

Currently, there is no known method of prevention of HS.