Hidradenitis Suppurativa

Everything about the causes, symptoms, and treatments of abscess formation in skin folds.

Symptoms and Causes

Hidradenitis suppurativa, also known as hidrosadenitis or inverse acne, is a non-contagious inflammatory disease characterized by the formation of small, painful nodules beneath the skin, commonly referred to as "boils." It is a chronic condition in which symptoms manifest intermittently in flares of varying intensity.

These nodules primarily appear in large skin folds, such as the axillae, groin, external genitalia, buttocks, perineal area (between the anus and the genitalia), perianal region (around the anus), and, in women, the submammary region—areas with higher sweat and sebaceous gland density or where skin friction is increased.

Specialists do not always identify hidradenitis suppurativa easily, as the symptoms are nonspecific. Therefore, diagnosis often takes several years, although significant advances are being made in this area.

Hidradenitis suppurativa has no cure; treatment focuses on alleviating symptoms and extending periods between flares to improve patients’ quality of life. Prognosis varies depending on patient characteristics and disease severity but is generally favorable when specialist guidelines are followed.

Symptoms

Common symptoms of hidradenitis suppurativa include:

Painful nodules: small lumps that become inflamed in areas of sensitive skin.
Abscesses: pus-filled nodules that, in addition to causing pain, produce malodorous discharge.
Scars: lesions leave deep marks when resolved.
Keloids: excessive scar tissue growth due to collagen overproduction, protruding from the skin.
Fistulas (advanced stages): abscesses deepen and interconnect, forming subcutaneous tunnels that cause intense pain.

Causes

Hidradenitis suppurativa arises from obstruction of a hair follicle. It is usually a consequence of an inflammatory reaction, although not all causes are fully understood.

Contrary to common belief, it is not a contagious disease.

Risk Factors

The main risk factors for hidradenitis suppurativa are:

Age: most common during adolescence and early adulthood (around the twenties).
Sex: slightly more frequent in women.
Race/ethnicity: appears more frequently in Black individuals, possibly due to genetic factors.
Overweight and obesity.
Severe acne.
Arthritis.
Diabetes.
Chronic inflammatory diseases.
Smoking.
Genetic predisposition: multiple cases often occur within the same family.
Certain medications: including lithium or tyrosine kinase inhibitors.

Complications

Hidradenitis suppurativa can cause the following complications:

Secondary infection in areas adjacent to nodules.
Skin changes, potentially leaving scars.
Limited mobility due to scar tissue.
Swelling of arms, legs, or genitalia from impaired lymphatic drainage.
Chronic pain.
Skin cancer: long-standing lesions, especially in the perianal region, may develop into squamous cell carcinoma.
Low self-esteem.
Anxiety.
Depression.
Social isolation due to lesion location, odor, and discharge.

Prevention

Although hidradenitis suppurativa cannot always be prevented, symptoms are less severe and flares less frequent if healthy lifestyle habits are maintained, such as:

Not smoking.
Maintaining a healthy weight.
Proper hygiene, avoiding irritating products.
Keeping skin folds dry.
Avoiding traditional hair removal methods (shaving or waxing).
Wearing loose cotton clothing to reduce friction.
Following a healthy diet.
Engaging in regular, moderate physical activity.

Which Specialist Treats Hidradenitis Suppurativa?

Hidradenitis suppurativa falls under the specialty of medical-surgical dermatology and venereology.

Diagnosis

As previously noted, diagnosing hidradenitis suppurativa is challenging. In some cases, it can take ten to twelve years due to symptom overlap with other conditions.

Clinical evaluation is the cornerstone of diagnosis, as the presence of suppurative nodules or fistulas in skin folds is a clear indicator. Ultrasound may be performed to determine the actual extent of abscesses.

Treatment

Treatment of hidradenitis suppurativa is individualized according to the patient’s needs and prior response to flares. Often, multiple approaches are combined to achieve optimal outcomes. Key treatments include:

Topical medications: antibiotics reduce nodule size, and antibacterial products prevent flare-ups. Corticosteroids are used for acute inflammation.
Systemic medications: oral drugs act throughout the body, not only on affected areas, and are used in severe cases. Commonly prescribed are antibiotics or immunosuppressive agents.
Biologic therapies: block proteins that drive chronic inflammation, particularly interleukin-17. Highly effective options include adalimumab, secukinumab, and bimekizumab.
Laser hair removal: permanent hair elimination in skin folds prevents nodule formation.
Abscess drainage: a palliative procedure that relieves pain and reduces inflammation by incising the abscess to remove pus and clean the area.
Fistula unroofing: a minimally invasive surgical procedure that removes the top of the tunnel to clean it, allowing spontaneous healing.
Surgical intervention: larger incisions remove the abscess and affected skin, followed by reconstruction with skin grafts or flaps for a natural appearance.