Dermatology · Inflammatory Skin Conditions
The facts most likely to be tested
Hidradenitis suppurativa is a chronic inflammatory follicular occlusion disorder primarily affecting intertriginous areas such as the axillae, groin, and perineum.
The clinical hallmark is the presence of recurrent, painful nodules, abscesses, sinus tracts, and double-ended comedones (bridge scars).
The Hurley staging system is used to classify disease severity, which dictates the appropriate therapeutic approach.
First-line medical management for mild disease involves topical clindamycin, while moderate-to-severe disease requires oral tetracyclines (e.g., doxycycline).
Adalimumab is the only FDA-approved TNF-alpha inhibitor for the treatment of moderate-to-severe hidradenitis suppurativa.
Surgical intervention, including deroofing or wide local excision, is indicated for refractory sinus tracts and chronic, deep-seated lesions.
Smoking cessation and weight loss are critical lifestyle modifications that significantly reduce disease flares and improve long-term outcomes.
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A 24-year-old female presents with a 2-year history of recurrent, painful lumps in her axillae and groin. Physical examination reveals multiple erythematous nodules, purulent drainage, and fibrotic sinus tracts in the bilateral axillary regions. She has a history of smoking one pack of cigarettes daily. She has previously failed multiple courses of topical antibiotics. There are no signs of systemic infection.
What is the most appropriate next step in the management of this patient's condition?
Initiation of a TNF-alpha inhibitor (e.g., Adalimumab)
The patient presents with moderate-to-severe hidradenitis suppurativa (Hurley stage II/III) that has failed topical therapy, necessitating systemic treatment with a biologic agent like adalimumab.
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Etiology / Epidemiology
Chronic inflammatory disease of apocrine gland-bearing skin; strongly associated with obesity and smoking.
Clinical Manifestations
Recurrent, painful double-comedones and sinus tracts in intertriginous areas.
Diagnosis
A clinical diagnosis based on history of recurrent lesions in characteristic locations.
Treatment
Mild disease: topical clindamycin; moderate/severe: adalimumab.
Prognosis
High risk of squamous cell carcinoma in chronic, non-healing wounds.
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Epidemiology & Etiology
Common in females (3:1 ratio) with onset typically post-puberty. Strong genetic predisposition noted in 30% of cases. Smoking and obesity are the most significant modifiable risk factors exacerbating disease severity.
Pertinent Anatomy
Affects intertriginous zones including axillae, inguinal, perineal, and inframammary regions. These areas are rich in apocrine glands and hair follicles, which serve as the primary site of follicular occlusion.
Pathophysiology
Begins with follicular hyperkeratosis leading to ductal occlusion and rupture. Subsequent bacterial colonization triggers a robust inflammatory response, resulting in abscesses and sinus tracts. Chronic inflammation leads to extensive fibrosis and scarring.
Clinical Manifestations
Presents as painful, erythematous nodules that progress to double-comedones (pathognomonic). Patients develop sinus tracts and bridge scarring in the axilla or groin. Sepsis or cellulitis are rare but serious acute complications.
Diagnosis
Primarily a clinical diagnosis. No specific laboratory test exists. The Hurley staging system is used to classify severity (Stage I: abscesses; Stage II: sinus tracts; Stage III: diffuse involvement).
Treatment
First-line for mild disease is topical clindamycin. For moderate-to-severe cases, adalimumab is the only FDA-approved biologic. Avoid systemic corticosteroids for long-term management due to limited efficacy and side effects. Surgical excision is reserved for refractory, localized disease.
Prognosis
Chronic, relapsing course requiring long-term management. Squamous cell carcinoma is a rare but critical long-term complication of chronic, draining sinus tracts. Monitor for signs of malignant transformation in non-healing ulcers.
Differential Diagnosis
Furunculosis: usually solitary, lacks sinus tracts
Lymphadenitis: associated with systemic symptoms/lymphadenopathy
Crohn's disease: check for perianal fistulas and GI symptoms
Actinomycosis: presents with sulfur granules and woody induration
Folliculitis: superficial, lacks deep scarring/tracts