Hydradenitis suppurativa (HS)

Clinical Presentation and Diagnosis of Hidradenitis Suppurativa

Symptoms and Disease Progression

Hidradenitis Suppurativa typically begins with the development of solitary or multiple painful, deep-seated nodules or papules in the affected areas. The clinical course is chronic and relapsing, with lesions progressing through several stages:

1. Early Lesions: At the onset of the disease, at the site of inflammation, there is often an itching sensation or discomfort. A very painful, firm or rubbery swelling (nodule or papule) appears, ranging in diameter from several millimeters to 1-2 cm. This lesion is dense to the touch.
2. Abscess Formation: Gradually, the size of the swelling and the intensity of pain increase. The overlying skin turns purple-red (erythematous to violaceous). The center of the swelling (nodule) often softens (becomes fluctuant) as pus accumulates, forming an abscess. This abscess may spontaneously rupture and drain creamy, sometimes foul-smelling, pus through a formed opening.
3. Sinus Tracts and Scarring: The development cycle of a single inflammatory infiltrate or abscess typically lasts 10-15 days. However, healing is often completed by scar formation. With recurrent episodes, chronic inflammation leads to the development of interconnected sinus tracts (tunnels beneath the skin that drain pus) and hypertrophic or "bridge" scars.
4. Widespread Involvement: Often, neighboring hair follicles and apocrine glands become involved in the inflammatory process. In such cases, an extensive, very painful, indurated (hardened) infiltrate forms, and the overlying skin becomes bumpy and irregular. With the successive involvement of more and more sweat glands and follicles, the disease process can be significantly prolonged, lasting for months or even years, with periods of flare-ups and remissions.

The disease is often accompanied by a significant systemic reaction during acute flare-ups, including an increase in body temperature (fever), headache, general malaise, and leukocytosis (elevated white blood cell count) in blood tests. Hidradenitis Suppurativa frequently recurs. If treatment is incorrect, delayed, or ineffective, exacerbations of the disease can be repeated dozens of times, leading to progressive scarring and disability.

Diagnostic Considerations

The diagnosis of Hidradenitis Suppurativa is primarily clinical, based on three key criteria:

1. Typical Lesions: Presence of characteristic painful, deep-seated nodules, abscesses, draining sinus tracts, and "bridge" scars.
2. Typical Anatomical Locations: Involvement of axillae, groin, perineal/perianal area, inframammary folds.
3. Chronic and Relapsing Nature: History of recurrent outbreaks over months or years.

No specific laboratory test confirms HS, but tests may be done to rule out other conditions or assess for secondary infection or systemic inflammation. Biopsy is rarely needed for typical cases but may be performed for atypical presentations or to exclude malignancy (e.g., squamous cell carcinoma, which can rarely arise in chronic HS lesions).

Severity is often assessed using staging systems like the Hurley Staging System:

• Hurley Stage I: Solitary or multiple abscesses without sinus tracts or scarring.
• Hurley Stage II: Recurrent abscesses with sinus tract formation and scarring, separated by normal skin.
• Hurley Stage III: Diffuse or near-diffuse involvement, or multiple interconnected sinus tracts and abscesses across an entire area.

Treatment Strategies for Hidradenitis Suppurativa

The management of Hidradenitis Suppurativa is often challenging and aims to control inflammation, manage pain, prevent new lesions, treat existing lesions, and minimize scarring and long-term complications. A multidisciplinary approach involving dermatologists, surgeons, and sometimes other specialists is often beneficial. Treatment choice depends on the severity (Hurley stage) and extent of the disease.

Medical Management

• Topical Therapies:
  • Antiseptic Washes: Chlorhexidine or benzoyl peroxide washes can help reduce bacterial load on the skin.
  • Topical Antibiotics: Clindamycin solution or lotion is commonly used, especially for mild disease or as an adjunct.
  • Pure ichthyol (ichthammol) ointment was historically applied to lesions to help draw out inflammation.
• Systemic Antibiotics:
  • Often started early in acute flares to control infection and inflammation. Common choices include tetracyclines (e.g., doxycycline, minocycline) for their anti-inflammatory properties, or combinations like clindamycin and rifampicin for more severe or refractory disease. Long-term courses may be needed.
• Intralesional Corticosteroids: Injections of triamcinolone directly into painful inflammatory nodules can provide rapid relief of pain and swelling.
• Systemic Corticosteroids: Short courses of oral corticosteroids (e.g., prednisone) may be used for severe acute flare-ups to quickly reduce inflammation, but long-term use is avoided due to side effects.
• Hormonal Therapies: Antiandrogen therapies like spironolactone, oral contraceptives (especially those with antiandrogenic progestins), or finasteride may be beneficial for some women with HS, particularly if symptoms flare with menstrual cycles.
• Retinoids: Oral retinoids like acitretin or isotretinoin have shown variable efficacy and are not first-line treatments but may be considered in some cases.
• Biologic Agents: For moderate to severe HS unresponsive to conventional therapies, biologic drugs targeting specific inflammatory cytokines have become important. Adalimumab (an anti-TNF-alpha agent) is approved for HS. Other biologics are under investigation.
• Pain Management: NSAIDs or other analgesics are important for managing the significant pain associated with HS.

Surgical Interventions

Surgical approaches are often necessary for more advanced or refractory HS:

• Incision and Drainage (I&D): Provides temporary relief for acute, fluctuant abscesses but does not address the underlying chronic inflammation or prevent recurrence.
• Deroofing (Uncovering of Sinus Tracts): Involves surgically removing the "roof" of sinus tracts and allowing them to heal by secondary intention. This can be effective for limited areas of sinus tract formation.
• Limited Excision: Removal of individual persistent nodules or localized areas of sinus tracts.
• Wide Local Excision: Surgical removal of the entire affected area of skin and subcutaneous tissue, including all involved follicles, sinus tracts, and scar tissue. This is typically reserved for severe, extensive disease (Hurley Stage III). The resulting defect may require healing by secondary intention, skin grafting, or flap reconstruction.
• Laser Ablation: CO2 laser or Nd:YAG laser can be used to ablate (destroy) lesions or excise tissue.

With timely and modern multimodal treatment, recovery can often be achieved in 5-15 days for acute flares, although the chronic nature of HS means that relapses of the disease are possible, especially if underlying contributing factors are not managed.

Lifestyle and Supportive Measures

• Weight Management: Weight loss in overweight or obese individuals can reduce skin friction and inflammation.
• Smoking Cessation: Strongly advised as smoking is a major exacerbating factor.
• Dietary Modifications: Some patients report improvement with avoidance of dairy or brewer's yeast, but evidence is limited and individualized.
• Loose-Fitting Clothing: To reduce friction in affected areas.
• Wound Care: Proper care of draining lesions with appropriate dressings. Dressings with hypertonic solution have been mentioned historically after opening hidradenitis.
• Psychological Support: HS can have a significant impact on quality of life, self-esteem, and mental health. Counseling or support groups can be beneficial.

Prevention of Hidradenitis Suppurativa Exacerbations

While there is no definitive way to prevent the onset of Hidradenitis Suppurativa in susceptible individuals, certain measures can help manage the condition and reduce the frequency or severity of flare-ups (exacerbations). Prevention is mainly focused on personal hygiene, avoiding known triggers, and maintaining overall health:

• Maintain Good Personal Hygiene: Regular showering or bathing is necessary. Gently cleanse affected or prone areas with mild, non-irritating soaps or antiseptic washes (e.g., chlorhexidine-based).
• Keep Affected Areas Dry: Moisture can exacerbate HS. Pat skin dry thoroughly after washing. Consider using absorbent powders (talc-free) in skin folds if appropriate.
• Wear Loose-Fitting Clothing: Avoid tight clothing that can cause friction and irritation in areas like the armpits, groin, and buttocks. Choose breathable fabrics like cotton.
• Avoid Trauma to Affected Areas:
  • Shaving: Frequent shaving of hair in affected areas (e.g., armpits) is generally not recommended as it can cause micro-trauma and irritation, potentially triggering flares. If hair removal is desired, consider alternatives like laser hair removal (which can sometimes be beneficial for HS) or gentle trimming.
  • Avoid picking, squeezing, or traumatizing existing lesions.
• Weight Management: If overweight or obese, achieving and maintaining a healthy weight can reduce skin-on-skin friction and may lessen inflammatory burden.
• Smoking Cessation: Smoking is a significant risk factor and can worsen HS. Quitting smoking is strongly advised.
• Dietary Considerations: Some individuals find that certain foods may trigger their HS (e.g., dairy products, sugary foods, brewer's yeast). While evidence is not definitive for all, keeping a food diary and observing personal triggers might be helpful.
• Manage Stress: Stress can sometimes exacerbate inflammatory conditions. Employ stress-reduction techniques.
• Avoidance of Certain Deodorants/Antiperspirants (if irritating): Some products can irritate the skin. Opt for gentle, fragrance-free options. The use of depilatory agents (hair removal creams) should also be approached with caution as they can be irritating.
• Disinfectant Solutions (Historical/Adjunctive): Wiping the axillary area with disinfectant solutions like boric alcohol, simple ethyl alcohol, cologne, or specific deodorants was a historical preventive suggestion. Modern advice focuses more on gentle cleansing and avoiding irritants.

If abscess formation does occur as part of the HS process, surgical treatment, involving opening (incision) and drainage of the purulent focus, is often employed as part of acute management, alongside appropriate medical therapy.

 

Differential Diagnosis of Inflammatory Lesions in Intertriginous Areas

Hidradenitis Suppurativa needs to be distinguished from other conditions that can cause recurrent inflammatory nodules, abscesses, or cysts in the axillae, groin, and other intertriginous areas:

 

Complications and Long-Term Impact of HS

HS is a chronic condition that can lead to significant physical and psychosocial complications:

• Chronic Pain: A major feature, significantly impacting quality of life.
• Scarring and Contractures: Can lead to disfigurement and restricted movement, especially in the axillae.
• Sinus Tract Formation and Chronic Drainage: Leading to malodor and hygiene challenges.
• Recurrent Infections and Abscesses.
• Lymphedema: Chronic inflammation can sometimes impair lymphatic drainage, leading to swelling.
• Psychosocial Impact: Depression, anxiety, social isolation, low self-esteem, and impaired sexual function are common due to pain, odor, appearance of lesions, and chronic nature of the disease.
• Anemia of Chronic Disease.
• Arthritis: An inflammatory arthritis can be associated with HS.
• Squamous Cell Carcinoma: Rarely, long-standing, chronic HS lesions can undergo malignant transformation into squamous cell carcinoma.
• Amyloidosis: Very rare, but can occur with severe, long-term chronic inflammation.

 

When to Seek Specialist Care

Individuals experiencing symptoms suggestive of Hidradenitis Suppurativa should consult a dermatologist, who is typically the primary specialist for managing this condition. Referral to a surgeon (general or plastic) may be necessary for surgical interventions. Key indications for seeking specialist care include:

• Recurrent, painful nodules or boils in typical HS locations (armpits, groin, buttocks, under breasts).
• Lesions that drain pus or form tunnels (sinus tracts) under the skin.
• Significant scarring in affected areas.
• Symptoms that are not controlled by simple home care or primary care interventions.
• A significant impact on quality of life, work, or social activities.

Early diagnosis and a comprehensive, long-term management plan tailored by a specialist knowledgeable in HS are crucial for controlling the disease, minimizing complications, and improving patient outcomes.