Hidradenitis suppurativa (hi-drad-uh-NI-tis sup-u-ra-TI-va) is a chronic skin inflammation marked by the presence of blackheads and one or more red, tender bumps (lesions). The lesions often enlarge, break open and drain pus. Scarring may result after several recurrences. Considered a severe form of acne (acne inversa), hidradenitis suppurativa occurs deep in the skin around oil (sebaceous) glands and hair follicles. The parts of the body affected — the groin and armpits, for example — are also the main locations of apocrine sweat glands. Hidradenitis suppurativa tends to start after puberty, persist for years and worsen over time. Early diagnosis and treatment of hidradenitis suppurativa can help manage the symptoms and prevent new lesions from developing.

Complications of Hidradenitis Suppurativa

Hidradenitis suppurativa often causes complications when the disease is persistent and severe. These complications include:

• Sinus tracts or tunnels that connect and form a network under the skin. The tracts prevent the sores from healing and cause more sores to develop.
• Scars and skin changes. Severe hidradenitis suppurativa may leave thick, raised scars, pitted skin or patches of skin that are darker than normal (hyperpigmentation).
• Restricted movement. The disease may cause limited or painful movement, especially when it affects the armpits or thighs.
• Cellulitis. This potentially serious bacterial infection appears as an area of swollen, red skin that feels hot and tender and that may spread rapidly. Although the initial infection may be superficial, it eventually can affect the tissues underlying your skin or spread to your lymph nodes and bloodstream.

Causes of Hidradenitis Suppurativa

• Hidradenitis suppurativa occurs deep in the skin around oil (sebaceous) glands, apocrine sweat glands and hair follicles. The apocrine sweat glands release fluid, dead skin cells and other substances into the hair follicle. This mixes with the oil from the sebaceous gland. Hidradenitis suppurativa develops when the oil glands and hair follicle openings become blocked with these substances. When oils and other skin products become trapped, they push into surrounding tissue. Bacteria can then trigger infection and inflammation.
• It's not known why this blockage occurs, but a number of factors — including hormones, genetics, cigarette smoking and excess weight — may all play a role.
• Sometimes hidradenitis suppurativa occurs with other diseases, such as Crohn's disease, herpes simplex or Grave's disease.

Signs & Symptoms of Hidradenitis Suppurativa

Hidradenitis suppurativa commonly occurs around hair follicles where many oil and sweat glands are found, such as the armpits, groin and anal area. It may also occur in areas where skin rubs together, such as the inner thighs, under the breasts or between the buttocks. Hidradenitis suppurativa can affect a single area or multiple areas of the body.

Signs and symptoms of hidradenitis suppurativa include:

• Small pitted areas of skin containing blackheads, often appearing in pairs or a "double-barrel" pattern.
• One or more red, tender bumps (lesions) that fill with pus. The bumps often enlarge, break open and drain pus. The drainage may have an unpleasant odor. Itching, burning and excessive sweating may accompany the bumps.
• Painful, pea-sized lumps that grow under the skin. These hard lumps, which may persist for years, can enlarge and become inflamed.
• Painful bumps or sores that continually leak fluid. These open wounds heal very slowly, if at all, often leading to scarring and the development of tunnels under the skin.

Hidradenitis suppurative often starts at puberty with a single, painful bump that persists for weeks or months. For some people, the disease progressively worsens and affects multiple areas of their body. Other people experience only mild symptoms. Excess weight, stress, hormonal changes, heat or excessive perspiration can worsen symptoms. 

Diagnosis of Hidradenitis Suppurativa

To make a diagnosis, your doctor may ask about your symptoms and medical history, examine your skin, and order blood tests. If pus or drainage is present, your doctor may send a sample of the fluid to a laboratory for testing. This test is known as a culture. Such tests may be necessary to rule out other skin conditions, such as tuberculosis of the skin, a carbuncle or a pilonidal cyst.

Treatments of Hidradenitis Suppurativa

There is no cure for hidradenitis suppurativa. But early treatment can help manage the symptoms and prevent new lesions from developing. Treatments depend on the extent of the affected areas and whether the sores are painful or infected. Mild cases can be treated with self-care measures, including warm compresses and regular washings with antibacterial soap. Moderate cases may require medications, such as those you rub on the affected areas (topical medications) or those you take by mouth (oral medications). Possible medications include:

• Antibiotics to treat infection. Antibiotics taken for a long time early in the disease may prevent future outbreaks or prevent the disease from worsening.
• Oral retinoid medications to stop oil gland functions and to prevent the plugging of the hair follicle.
• Nonsteroidal anti-inflammatory drugs to reduce pain and swelling.
• Corticosteroids or immunosuppressant drugs.

For severe or persistent cases or for deep lesions, surgery may be necessary.

• Incision and drainage. Surgical drainage or removal of the lesions may be an option when the disease involves a single small area. However, this treatment won't prevent the disease from returning and is generally used for short-term relief.
• Uncovering the tunnels or tracts. Cutting away skin and flesh that cover any tunnels or tracts can increase healing of the lesions and minimize scarring. This doesn't prevent the disease from returning in the treated area or another area of the body, however.
• Surgical removal. Surgical treatment of recurrent or severe symptoms involves removal of all involved skin followed by direct closure with skin flaps or with skin grafting (removing skin from one area of your body and attaching it to another). Full surgical removal of the affected areas can treat the disease that is present but doesn't prevent the disease from occurring in other areas. Obesity, incomplete removal and ongoing skin infections can increase the chances that hidradenitis suppurativa returns, even after surgical treatment.

When to seek Medical Advice

Mild cases of hidradenitis suppurativa may be treated with self-care measures. But if the condition doesn't improve in one to two weeks, appears in several locations, recurs often or is painful, consult your doctor or a dermatologist. Most often, medical treatments - such as prescription medications or surgery - are necessary to manage the problem.