Overview
Definition:
Hidradenitis suppurativa (HS), also known as acne inversa, is a chronic, relapsing, inflammatory follicular disease affecting apocrine gland-bearing skin areas, primarily the axillae, groin, and anoperineal regions
In adolescents, it presents a unique challenge due to ongoing pubertal development and impact on quality of life.
Epidemiology:
HS typically begins after puberty, with onset often in the late teens or early twenties, making its manifestation in adolescents a significant concern
Prevalence estimates vary but it affects up to 1-4% of the global population
Adolescents may experience more aggressive disease progression.
Clinical Significance:
HS in adolescents can lead to significant physical discomfort, pain, scarring, and psychosocial distress, impacting school attendance, social interactions, and self-esteem
Early diagnosis and appropriate management are crucial to prevent disease progression and long-term sequelae, making it a vital topic for pediatric and dermatology residents preparing for DNB and NEET SS exams.
Clinical Presentation
Lesion Types:
Primary lesions include comedones (double-ended or multiple openings), papules, pustules, nodules, abscesses, sinus tracts, and bridging scars
Lesions are typically tender, inflamed, and recurrent, often occurring in characteristic anatomical locations
Itching and malodor may also be present.
Disease Severity Staging:
The Hurley staging system is commonly used: Stage I (mild, no sinus tracts or scarring), Stage II (moderate, recurrent abscesses with some sinus tracts and scarring), and Stage III (severe, diffuse involvement with multiple interconnected sinus tracts and extensive scarring)
Adolescent HS may rapidly progress to moderate or severe stages.
Associated Conditions:
Adolescent HS can be associated with other conditions, including obesity, metabolic syndrome, polycystic ovary syndrome (PCOS) in females, inflammatory bowel disease (IBD), and acne vulgaris
A thorough history and examination are essential to identify these comorbidities.
Diagnostic Approach
History Taking:
Detailed history should include age of onset, pattern of lesion recurrence, anatomical distribution, impact on quality of life, previous treatments and their efficacy, family history of HS or inflammatory diseases, and presence of associated symptoms like joint pain or gastrointestinal issues
Inquire about triggers like hormonal fluctuations, diet, and stress.
Physical Examination:
A comprehensive examination of the affected areas is crucial, noting the type, distribution, and severity of lesions
Assess for nodules, abscesses, sinus tracts, and scarring
Palpate for fluctuant lesions indicating infection
Examine other skin areas, scalp, and nails for signs of associated conditions.
Investigations:
Diagnosis is primarily clinical
Laboratory investigations are usually not required for diagnosis but may be useful to assess inflammation (e.g., elevated ESR, CRP) or rule out comorbidities
Blood cultures may be considered for severe systemic infection
Biopsy is rarely indicated unless for atypical presentations or to rule out malignancy.
Differential Diagnosis:
Key differentials include severe acne vulgaris, folliculitis, cutaneous abscesses, pilonidal sinus disease, Crohn's disease with perianal involvement, and other rare inflammatory or infectious conditions
Characteristic location, chronicity, and scarring patterns help differentiate HS.
Management Antibiotics Vs Biologics
Goals Of Therapy:
Treatment aims to reduce inflammation, control infection, promote healing, prevent new lesions, minimize scarring, and improve quality of life
Management is often multimodal and tailored to disease severity and individual patient factors.
Role Of Antibiotics:
Antibiotics, particularly tetracyclines (doxycycline, minocycline), clindamycin, and rifampicin, are often used for their anti-inflammatory and antimicrobial properties in mild to moderate HS
They are most effective for controlling acute flares and reducing inflammation
Long-term use may be necessary but carries risks of resistance and dysbiosis
Dosing for adolescents typically follows adult guidelines adjusted for weight.
Role Of Biologics:
Biologics, particularly TNF-alpha inhibitors like adalimumab, are the mainstay for moderate to severe HS refractory to conventional therapies
Adalimumab is FDA-approved for moderate to severe HS
Other biologics are being investigated
Biologics target specific inflammatory pathways, offering significant disease control and improvement in quality of life
They require careful patient selection, screening for infections (e.g., TB), and ongoing monitoring.
Comparison And Transition:
Antibiotics are generally first-line for milder disease or acute flares
Biologics are indicated for moderate-to-severe disease unresponsive to antibiotics and other treatments
The choice depends on disease severity, patient comorbidities, and treatment response
Transition from antibiotics to biologics may be necessary as the disease progresses or if antibiotic efficacy wanes
Combination therapy with topical agents (e.g., clindamycin-niacinamide gel) and systemic treatments is often employed.
Medical Management
Topical Therapies:
Topical treatments include antiseptic washes (e.g., chlorhexidine, benzoyl peroxide), topical antibiotics (e.g., clindamycin), and topical retinoids in some cases
Their role is often adjunctive for mild disease or localized lesions.
Systemic Antibiotics:
Oral antibiotics such as doxycycline (50-100 mg BID), minocycline (50-100 mg BID), or combination therapy (e.g., clindamycin 300 mg BID + rifampicin 600 mg BID) are used for their anti-inflammatory and antibacterial effects
Treatment duration is typically 3-6 months
Careful monitoring for side effects is essential.
Hormonal Therapy:
For female adolescents, hormonal therapies like oral contraceptives or spironolactone may be considered if there is a suspicion of hormonal influence, particularly in cases associated with PCOS
However, evidence for efficacy in HS is limited.
Oral Retinoids:
Isotretinoin has shown some efficacy in smaller studies but is not a primary treatment due to potential teratogenicity and variable response
Acitretin may be an alternative in specific cases.
Biologic Therapy Details
Adalimumab:
Adalimumab is the most established biologic for moderate to severe HS
The typical adolescent dose is 40 mg weekly or 40 mg every other week, following adult dosing
It requires subcutaneous injection
Efficacy is evaluated after 12-16 weeks.
Other Biologics:
Research is ongoing into other biologics, including ustekinumab and brodalumab, which target IL-12/23 and IL-17 pathways, respectively
Their use in adolescents is often off-label and based on expert consensus.
Monitoring During Biologics:
Patients on biologics require regular monitoring for signs of infection, including reactivation of tuberculosis
Baseline screening for latent TB is mandatory
Regular blood work may be needed to monitor for potential systemic side effects
Immunization status should be up-to-date, avoiding live vaccines during treatment.
Surgical Considerations
Indications For Surgery:
Surgery is considered for patients with localized disease, chronic draining sinus tracts, significant scarring, or those who fail medical management
Incision and drainage are for acute abscesses.
Excision Procedures:
Wide local excision of affected areas, particularly for recurrent nodules and sinus tracts, can provide definitive treatment
Techniques include deroofing of sinus tracts, local excision, and plastic reconstruction (e.g., skin grafting).
Laser And Other Techniques:
Various other procedures like laser ablation, electrosurgery, and local excision of sinus tracts are also utilized, especially for less extensive disease or as adjuncts to medical therapy.
Complications
Scarring And Disfigurement:
Chronic inflammation and repeated abscesses lead to significant scarring, skin thickening, and disfigurement, impacting body image and function
Contractures can develop, particularly in the axillae and groin.
Secondary Infections:
Bacterial superinfections of lesions can occur, leading to increased pain, inflammation, and potential for systemic spread
Anaerobic bacteria are often implicated.
Fistula Formation:
Sinus tracts can form complex networks, leading to the development of persistent fistulas that are difficult to manage and can be a source of chronic pain and malodor.
Malignant Transformation:
Squamous cell carcinoma can rarely arise within long-standing, chronically inflamed HS lesions, particularly in Hurley Stage III disease
Regular dermatological surveillance is important.
Key Points
Exam Focus:
Understand the pathognomonic features of HS, Hurley staging, and the stepwise approach to management, emphasizing the transition from antibiotics to biologics for moderate-to-severe disease
Know the approved biologics and their general indications/contraindications.
Clinical Pearls:
Recognize that HS often presents in adolescence and can significantly impact quality of life
Early intervention with appropriate therapies can prevent disease progression and severe scarring
Always consider comorbidities and psychosocial support.
Common Mistakes:
Misdiagnosing HS as simple acne or folliculitis
Underestimating the severity and impact on quality of life
Delaying biologics in moderate-to-severe disease
Failing to screen for TB before initiating biologic therapy
Inadequate follow-up and management of scarring.