This is a condition much like acne, except that instead of affecting the face, it affects moist crevices in hair bearing areas, with the axilla and perianal region sometimes affected. When involving the perianal region, it should not be confused for a pilonidal sinus, which is an abscess in the midline buttock crease.
Like severe acne, hidradenitis suppurativa is due to a bacterial infection of the skin, which results in blockage of the hair follicle. Like acne, this condition is influenced by hormones, with those in puberty and young adulthood particularly at risk and the elderly rarely affected. Smoking substantially increases the risk.
Presentation
Lesions typically begin similar to facial acne, with pimples coalescing to form a cluster of pimples (carbuncle) which can develop into an abscess. In complex cases, recurrent attacks lead to disfiguring scaring of the area and can result in the formation of a fistula.
Investigations
Up to 40% of cases have underlying Crohn’s disease, and therefore a biopsy is recommended to exclude this condition.
Severity
The severity of hidradenitis suppurativa is traditionally classified using the Hurley stages and can be useful to guide management:
- Hurley Stage I – abscess formation (single or multiple) without sinus tracts and cicatrisation
- Hurley Stage II – single or multiple, widely separated recurrent abscesses with tract formation and
- cicatrisation.
- Hurley Stage III – multiple interconnected tracts and abscesses throughout an entire area.
Management
A stepwise approach to management is recommended. Importantly, those who smoke should quit. Attention should be given perineal hygiene. Topical antiseptics and antibacterial soaps such as hexachlorophene (pHisohex®) used for acne can also be used for the perianal region.
Medical management is only useful for the first two stages of disease. Clindamycin 2% cream applied daily is very effective, and as effective as oral antibiotics [1]. In women, medications containing cyproterone acetate either on their own (Androcur®) or in combination with an oral contraceptive agent (Diane-35 ED+®), have been shown to be useful in early disease with remission achieved in about a third [2].
Surgery
Surgery is only indicated for advanced, Hurley stage 3 disease, where there are multiple interconnected tracts and abscesses throughout an entire area. Here the aim is excision of the affected area with skin grafting or advancement or rotation flaps. For perianal hidradenitis, a temporary stoma may be required for 3 months to allow complete healing of the area. For axillary hidradenitis, rotation flaps such as the Rhomboid flap have higher success than skin grafts (Figure 1).
References
- Jemec GB, Wendelboe P. Topical clindamycin versus systemic tetracycline in the treatment of hidradenitis suppurativa. J. Am. Acad. Dermatol 1998; 39(6): 971-974.
- Lam J et al. Hidradenitis Suppurativa (Acne inverse): Management of Recalcitrant Disease. Pediatric Dermatology 2007; 24 (5):465-473.
