Hidradenitis Suppuritiva
/Admittedly we are not dermatologists… but hydradenitis suppuritiva (HS) affects a substantial number of our patients and because of the locations it affects, OB/GYNs are often the first to see it.
What is HS?
Chronic, recurrent inflammatory disease of apocrine sweat glands
Also known as acne inversa
Located usually in axillae, groin, genitals, perineal, buttocks, and inframammary areas
Women tend to be more affected than men
Prevalence
1%-4%, onset usually between puberty - 40 years of age, usually in second or third decade of life
Why do we care?
Can cause significant pain, issues with scarring
May have huge impact on self-esteem and quality of life can be severe, thus importance of early diagnosis and treatment
Very rarely, squamous cell carcinomas develop within sites of HS
How do we recognize it and diagnose it?
Pathogenesis
Follicular occlusion is most likely the even that is responsible for the initial development of HS lesions; may be due to ductal keratinocyte proliferation → hyperkeratosis and plugging
There is then follicular rupture → formation of sinus tracts
Associated factors
Genetics
Mechanical stress (ie. pressure, friction, etc.),
Obesity (maybe...but it’s also present in those without obesity),
Smoking (strong correlation; majority of affected patients are smokers),
Hormones (some people may experience perimenstrual flares)
History and Physical exam
Typical lesions, typical locations, relapses and chronicity
Inflammatory nodules - first lesion is single, painful, deep-seated inflamed nodule in the intertriginous area; diagnosis is usually missed at his stage; can be diagnosed as a “boil” or furunculosis
After some time, the nodule can progress to form an abscess → may open to skin surface spontaneously
Pain usually improves after drainage
Sinus tracts - skin tunnels; can happen if HS is persistent for months or years; can release blood-stained, seropurulent, malodorous discharge periodically
Comedones - can appear with longstanding HS
Scarring - healed areas can have individual, pitted, acneiform scars; may be atrophic or keloidal
Lab studies - usually not needed, but if you’re uncertain, can do skin biopsy → r/o squamous cell carcinoma
Differential Diagnosis
Folliculitis, acne vulgaris, pilonidal disease, Crohn disease
Stage II disease — image courtesy of Wikimedia commons.
Stage III disease with active infection ongoing -- image courtesy of Wikimedia Commons.
What is the Hurley Staging System? - divides patients with HS into three disease severity groups:
Stage I: Abscess formation (single or multiple) without sinus tracts and cicatrization/scarring
Stage II: Recurrent abscesses with sinuses tracts and scarring, single or multiple widely separated lesions
Stage III: Diffuse or almost diffuse involvement, or multiple interconnected sinus tracts and abscesses across the entire area.
How do we manage HS, and when should we refer out?
Goals
Reduce formation of new areas, sinus tracts, and scarring
Treat existing lesions and reduce symptoms
Minimize psychological morbidity
For all patients
Education, psychological support if needed - it’s a chronic disease, not due to poor hygiene. Course can vary from person to person
Wound and skin care techniques
Pain management - NSAIDS usually, but discuss opioid analgesia if needed
Treat associated symptoms and conditions
Encourage smoking cessation if they smoke
Stage I - Aim is to reduce burden of disease
Topical clindamycin - can reduce inflammatory lesions; usually applied 2x/day
If fail topical therapy → oral therapy
Oral tetracyclines: 100 mg doxycycline daily or BID
If oral antibiotic therapy achieves good disease control, patients can stop and continue with topical clindamycin for maintenance
Antiandrogenic agents - spironolactone and finasteride; can be used, but they should NOT be given if there is possibility patient is pregnant
Oral contraceptives - very small study that showed some improvement
Metformin - can help promote weight loss, which can help HS
For acute symptomatic lesions - warm compress
May want to refer out for this: possibility of intralesional corticosteroid injections
Unroofing the area over the nodule
I&D - not advised for routine treatment. It can lead to immediate relief, but can promote lesion recurrence and scarring
Stage II and III - Can try everything above, but if not working, usually this is when we would say you should refer out for other treatments
If they don’t achieve good control with antibiotics, metformin or antiandrogenic therapy, may require oral retinoids, dapsone and biologics
We’ll mention some, but we won’t go into detail, since we don’t really do this stuff as Ob/Gyns
Oral retinoids - may only have limited benefit
Oral dapsone - sulfone drug with immunomodulatory and antibacterial properties
Adalimumab - FDA approved treatment for moderate to severe HS
Acute symptomatic lesions: oral glucocorticoids may also be used
For severe, refractory disease
Wide excision - extensive surgical intervention can get to greatest likelihood for resolution of active inflammation, but can be disfiguring and involve a prolonged recovery time.