What is hidradenitis suppurativa?
Hidradenitis suppurativa is an inflammatory skin disease that affects apocrine gland-bearing skin in the axillae, in the groin, and under the breasts. It is characterised by recurrent boil-like nodules and abscesses that culminate in pus-like discharge, difficult-to-heal open wounds (sinuses) and scarring.
The term hidradenitis implies it starts as an inflammatory disorder of sweat glands, which is now known to be incorrect. Hidradenitis suppurativa is also known as acne inversa.
Who gets hidradenitis suppurativa?
Hidradenitis often starts at puberty, and is most active between the ages of 20 and 40 years, and in women, can resolve at menopause. It is 3 times more common in females than in males. Risk factors include:
- Other family members with hidradenitis suppurativa
- Obesity and insulin resistance/metabolic syndrome
- Cigarette smoking
- Follicular occlusion disorders: acne conglobata, dissecting cellulitis, pilonidal sinus
- Inflammatory bowel disease (Crohn disease)
- Rare autoinflammatory syndromes associated with abnormalities of PSTPIP1 gene*
* PAPA syndrome (Pyogenic Arthritis, Pyoderma gangrenosum and Acne), PASH syndrome (Pyoderma gangrenosum, Acne, Suppurative Hidradenitis) and PAPASH syndrome (Pyogenic Arthritis, Pyoderma gangrenosum, Acne, Suppurative Hidradenitis)
What causes hidradenitis suppurativa?
Hidradenitis suppurativa is an autoinflammatory disorder. Although the exact cause is not yet understood, contributing factors include:
- Friction from clothing and body folds
- Aberrant immune response to commensal bacteria
- Follicular occlusion
- Release of pro-inflammatory cytokines
- Inflammation causing rupture of the follicular wall and destroying apocrine glands and ducts
- Secondary bacterial infection
What are the clinical features of hidradenitis suppurativa?
Hidradenitis can affect a single or multiple areas in the armpits, neck, submammary area, and inner thighs. Anogenital involvement most commonly affects the groin, mons pubis, vulva (in females), sides of the scrotum (in males), perineum, buttocks and perianal folds.
- Open and closed comedones
- Painful firm papules and larger nodules
- Pustules, fluctuant pseudocysts and abscesses
- Pyogenic granulomas
- Draining sinuses linking inflammatory lesions
- Hypertrophic and atrophic scars
The severity and extent of hidradenitis suppurativa is recorded at assessment and when determining the impact of a treatment. The Hurley system describes three distinct clinical stages:
- Solitary or multiple, isolated abscess formation without scarring or sinus tracts
- Recurrent abscesses, single or multiple widely separated lesions, with sinus tract formation
- Diffuse or broad involvement, with multiple interconnected sinus tracts and abscesses.
Severe hidradenitis (Hurley Stage 3) has been associated with:
What is the treatment for hidradenitis suppurativa?
- Weight loss; follow low-glycaemic, low-dairy diet
- Smoking cessation: this can lead to improvement within a few months
- Loose fitting clothing
- Daily unfragranced antiperspirants
- If prone to secondary infection, wash with antiseptics or take bleach baths
- Apply hydrogen peroxide solution or medical grade honey to reduce malodour
- Apply simple dressings to draining sinuses
- Analgesics, such as paracetamol (acetaminophen), for pain control.
Medical management of hidradenitis suppurativa
Medical management of hidradenitis suppurativa is difficult. Treatment is required long term. Effective options are listed below.
- Topical clindamycin, with benzoyl peroxide to reduce bacterial resistance
- Short course of oral antibiotics for acute staphylococcal abscesses, eg flucloxacillin
- Prolonged courses (minimum 3 months) of tetracycline, metronidazole, cotrimoxazole, fluoroquinolones or dapsone for their anti-inflammatory action
- Six-to-twelve week courses of the combination of clindamycin (or doxycycline) and rifampicin for severe disease
- Long-term oral contraceptive pill; antiandrogenic progesterones drospirenone or cyproterone acetate may be more effective than standard combined pills. These are more suitable than progesterone-only pills or devices.
- Spironolactone and finasteride
- Response takes 6 months or longer.
Immunomodulatory treatments for severe disease
- Intralesional corticosteroids into nodules
- Systemic corticosteroids short-term for flares
- Methotrexate, ciclosporin, and azathioprine
- TNFα inhibitors adalimumab and infliximab, used in higher dose than required for psoriasis, are the most successful treatments to date
Other medical treatments
- Metformin in patients with insulin resistance
- Acitretin (unsuitable for females of childbearing potential)
- Isotretinoin – more effective for acne
Surgical management of hidradenitis suppurativa
- Incision and drainage of acute abscesses
- Curettage and deroofing of nodules, abscesses and sinuses
- Laser ablation of nodules, abscesses and sinuses
- Wide local excision of persistent nodules
- Radical excisional surgery of entire affected areaa
- Laser hair removal
- van der Zee HH, Boer J, Prens EP, Jemec GB. The effect of combined treatment with oral clindamycin and oral rifampicin in patients with hidradenitis suppurativa. Dermatology. 2009;219(2):143-7. Epub 2009 Jul 8.
- Slade DEM, Powell BW, Mortimer PS. Hidradenitis suppurativa: pathogenesis and management. The British Association of Plastic Surgeons 2003; 56: 451-461
- Book: Textbook of Dermatology. Ed Rook A, Wilkinson DS, Ebling FJB, Champion RH, Burton JL. Fourth edition. Blackwell Scientific Publications.
- Buimer MG, Wobbes T, Klinkenbijl THG. Hidradenitis suppurativa British Journal of Surgery 2009:96;350-360
- Schrader AM, Deckers IE, van der Zee HH, Boer J, Prens EP. Hidradenitis suppurativa: a retrospective study of 846 Dutch patients to identify factors associated with disease severity. J Am Acad Dermatol. 2014 Sep;71(3):460-7.
- Zouboulis CC, Desai N, Emtestam L, Hunger RE, Ioannides D, Juhász I, Lapins J, Matusiak L, Prens EP, Revuz J, Schneider-Burrus S, Szepietowski JC, van der Zee HH, Jemec GB. European S1 guideline for the treatment of hidradenitis suppurativa/acne inversa. J Eur Acad Dermatol Venereol. 2015 Apr;29(4):619-44. doi: 10.1111/jdv.12966. Epub 2015 Jan 30. PubMed PMID: 25640693.
On DermNet NZ:
- Hidradenitis suppurativa (German version, January 2010)
- Sebaceous adenitis
- Follicular occlusion syndrome
- Hidradenitis suppurativa US National Library of Medicine Genetics Home Reference
- Hidradenitis Suppurativa – Medline Plus
- The Hidradenitis Suppurativa Trust
- HS-USA Support Group
- Hidradenitis Suppurativa Foundation, Inc.
- Dermatologic Manifestations of Hidradenitis Suppurativa – Medscape Reference
- Hidradenitis Suppurativa – British Association of Dermatologists