1 Chapter 19 Hidradenitis Suppurativa Peter Nthumba Hidradenitis suppurativa is a chronic, recurrent, painful inflammatory skin disease, first described in 1833 by a French surgeon. Verneuil, another French surgeon, in 1854 localized the pathology to sweat glands, giving rise to the eponym Verneuil s disease in use to date. In 1922, Schiefferdecker was officially credited with reporting its origins in the apocrine sweat glands. The actual pathogenesis remains unclear to date, with some investigators suggesting that this disease belongs in the realm of folliculitis, and not sweat glands. Hidradenitis suppurativa is a chronic disease of young and middle-aged people. Clinically, it may be intermittent or continuous in nature. Typically it finally will burn out in time, though it may remain active for many years. It affects 0.3% to 4% of the population; gender predilection is determined by site affected: Axillary disease female>male Perianal disease male>female Racial differences are not clear, although it is felt to be higher in those of African descent due to the greater concentration of apocrine sweat glands. Hidradenitis suppurativa is found in areas of apocrine gland-bearing skin: axilla, scalp, neck, inguinal area (with or without genital involvement), perineum, perianal, labial and gluteal region, but it may occur elsewhere in the body as well. Some authors have suggested that extra-axillary hidradenitis suppurativa lesions may be a premalignant state, and therefore a radical approach to their treatment from the outset would be justified. The lesions start as painful inflammatory papules that progress on to pustules, and then develop odiferous draining sinuses, leading to scarring, chronic fibrosis and deformity of involved areas. Scarring can be severe enough to limit range of motion. Most patients have experienced symptoms for 5-10 years prior to initial presentation. This is often due to social embarrassment. Hurley developed a classification in 1989 that is useful for the management and follow-up of patients. Sartorious et al proposed a more complex scoring system.
2 Table I Hurley s classification of Hidradenitis Suppurativa * Stage Clinical features I Single or multiple abscesses, without sinus tracts or cicatrization II Single or multiple recurrent abscesses, with tract formation and cicatrization, widely separated lesions. III Multiple interconnected abscesses and tracts across entire area, with diffuse or neardiffuse involvement Management Antibiotics Antibiotics and Surgery Surgery ( Modified from Hurley H. Dermatologic surgery, principles and practice, New York: Marcel Dekker, 1989; pp. 729 7, used by permission) Hidradenitis suppurativa has been reported to occur with a number of associations including: Follicular occlusion tetrad Pyoderma gangrenosum (acne conglobata, dissecting Synovitis cellulitis of the scalp and Acne syndrome pilonidal cyst) Hyperostosis Acne vulgaris Pustulosis Pyogenic arthritis Complications of hidradenitis suppurativa are numerous, including: Scarring and contractures Psychological impairment Fistula formation Malignancy (especially Complex regional pain squamous cell carcinoma syndrome most commonly in perianal Elephantiasis and gluteal lesions) Pathogenesis Although still controversial, current thinking on pathogenesis is that hidradenitis suppurativa is a follicular occlusion disease: hyperkeratosis with obstruction of follicular ducts leads to ductal dilatation and bacterial
3 superinfection, resulting in rupture, inflammation and abscess formation throughout the subcutaneous plane. Sinus track formation and scarring are the end results of this process. Hidradenitis (apocrine gland inflammation) is currently thought to be a secondary event. It is possible that these glands secrete a substance that triggers a cascade of events leading to hidradenitis suppurativa. Also thought to contribute to the disease are genetic, immunologic, hormonal (rarely occurs prior to puberty and after menopause), infective and host factors. Smoking has been suggested to inhibit glandular function and may be a predisposing factor. Diabetes, obesity and a tendency to develop acne have been identified as risk factors for the development of hidradenitis suppurativa. The actual roles that these factors play in the evolution of hidradenitis suppurativa are still unclear. Bacteriology As noted above, the role of bacteria in the causation of hidradenitis suppurativa is unclear. Sartorius et al in a study on the bacteriology of hidradenitis suppurativa found Coagulase negative staphylococci in all their patients; Corynobacteria spp were the next most common bacteria isolated. As in other studies, Staphylococcus aureus was not identified in this study. In all, gram positive cocci were the most commonly identified bacteria. Staphylococcus aureus has been identified in axillary hidradenitis suppurativa lesions in other studies, as have gram negative bacteria in perineal lesions. Medical treatment Medical treatment is reserved for Hurley s stage I (Figure 1) and early stage II. Topical and systemic antibiotic use has not shown any difference in outcomes, and despite widespread use of antibiotics, few studies have shown proof of their efficacy: recurrence is almost certain, even when antibiotic use has resulted in relief. Some studies have shown results suggesting that hormonal therapy (with antiandrogens) may be superior to the use of antibiotics. Also thought to contribute to the disease are genetic, immunologic, hormonal, infective and host factors.
4 Fig 1 Surgery Surgical excision offers the only possibility of cure for hidradenitis suppurativa. Surgical treatment options are guided by Hurley s stage at presentation, with stage III (Figure 2) and late stage II benefitting the most. Surgery may range from incision and drainage, de-roofing and marsupialization, local excision to radical wide excision, as dictated by the stage of presentation and the area affected. Where multiple areas are affected, the area with the most debilitating disease is treated first, followed by the other areas. Fig 2
5 Incision and drainage may be performed in acute settings, with fluctuant abscesses. A plan should be made to excise the involved tissue due to high recurrence rates following incision and drainage. De-roofing and marsupialization involve complete exposure of sinus tracts, leaving wounds which heal by secondary intention. Excellent outcomes have been reported. Radical wide excision of all involved skin is the only mode for cure; skin and subcutaneous tissue are excised down to deep fascia, with a margin of 1 to 2cm. to ensure that recurrence does not recur. Depending on the size of the defect, and the area involved (hence the need to ensure a cosmetically acceptable reconstruction), primary closure, skin grafting and/or the use of local flaps may be used. Table II: Defect reconstruction Method of defect Recurrence Comments reconstruction rates Primary skin closure 2.5% - 80% May compromise wound margins Local flap 18% Requires some knowledge on flaps Skin graft 13% May give poor aesthetic results Secondary healing 0% to 50% Requires prolonged follow-up and wound care (up to 30 weeks) Fig 3 Perianal: Excised with gluteal advancement flaps (Courtesy Dr. Blair Summitt) Recurrence rates after wide excision differ; this may be related to higher densities of apocrine glands in areas with higher recurrence rates.
6 Table III: Recurrence rates Region Recurrence rates Perianal 0% Axillary 3% Inguinal/perineal 37% Submammary 50% Other treatment modalities: Radiation therapy Radiation therapy has been used to treat patients with hidradenitis suppurativa. There is concern about the possibility of developing malignancy following radiation therapy, and therefore, its use is not recommended. In patients with recalcitrant hidradenitis suppurativa, radiation may give good results. Lasers and photodynamic therapy have also been used with some degree of success, as have many other treatment modalities.