Australian Doctor Australian Doctor 30th June 2017

Therapy Update Diffuse hidradenitis suppurative, with multiple connected sinus tracts and abscesses across the entire affected area. BOX 1. DIAGNOSING HS Clinical features • Recurrent painful inflamed abscesses and nodules in the axilla, genitofemoral, gluteal and inframammary regions • Comedones • Scarring • Sinus tracts • Family history Diagnostic criteria • A history of recurrent painful abscesses or suppurating lesions occurring in the characteristic locations (axilla, genitofemoral, perineum, gluteal area and inframammary) Axillary hidradenitis suppuritiva nine months post-surgery to excise the axillary sweat glands. from previous page Current evidence has demonstrated exces- sive TNF alpha in serum and lesions, among other inflammatory mediators, and clinical improvement with adalimumab therapy in HS patients lends great weight to this hypothesis. 12 Forty per cent of patients with HS report a fam- ily history, and this fig- ure is greater in those who develop early-onset disease (before the age of 13). 26 | Australian Doctor | 30 June 2017 BOX 2. DIFFERENTIATING BOILS FROM HS Boils • Superficial and pointed appearance • Isolated lesions • Red, swollen and tender • Normal surrounding skin • Hair-bearing areas • Usually infectious • Pruritus (folliculitis) Clinical manifestations and staging HS predominantly affects the intertriginous areas of the groin, axilla and inframammary folds. In men, the groin, perineal and perianal regions are most commonly involved. 14 Sites of compression and friction such as waistbands are also frequently implicated. HS lesions are typically sterile; however, antibiot- ics have been the mainstay of treatment, primarily for their anti-inflammatory properties in addition to their antimicrobial effects. 15 Inflammatory nodules are the hallmark of disease. Clusters of comedones, multiple nodules in a local- ised area, scarring and sinus tract formation are the product of persistent recur- rent disease. Scarring can present as dense fibrotic bands, or as thick and indurated skin overlying the entire axilla or groin. Severe scarring in the axilla may result in impaired lymphatic drain- age and mobility, and in the groin may cause lymphoe- dema of the vulvar area and pubis or the penile and scro- tal area in men. 16 • At least two episodes in a six-month period • Recurrent furunculosis is never associated with comedones HS lesions • Painful, firm nodules and abscesses • Deep-seated and round- topped • Recurrent lesions • Exclusively located in the axillae, the groin and/or in the inframammary regions • Lesions usually sterile • Scarring • Sinus tracts HS is diagnosed when there is a history of recur- rent painful abscesses or suppurating lesions occur- ring in the characteristic locations, with at least two episodes in a six-month period, and where there are hallmarks of chronic dis- ease such as sinus tracts and fibrotic scars. 17 Disease is classified according to severity in the Hurley staging system: Stage 1: Abscess forma- tion without sinus tracts and scarring (abscesses may be single or multiple). Stage 2: Recurrent abscesses with sinus tracts and scarring; single or multiple, widely separated lesions. Stage 3: Diffuse involve- ment, or abscesses across the entire area, and mul- boils. However, HS lesions are deep-seated and round topped, while furuncles characteristically have a more pointed appearance. HIDRADENITIS SUPPURATIVA PREDOMINANTLY AFFECTS THE INTERTRIGINOUS AREAS OF THE GROIN, AXILLA AND INFRAMAMMARY FOLDS. tiple interconnected sinus tracts. 18 HS is commonly misdi- agnosed as furunculosis, or Recurrent furunculosis is never associated with come- dones. Box 2 outlines the differentiating features of www.australiandoctor.com.au furunculosis compared with HS. Microscopy of swabs of lesions is generally not indi- cated and results are largely negative. Biopsy may be warranted to exclude other differential diagnosis such as cutaneous Crohn’s dis- ease (see box 3). ● Dr Charlton is a dermatology resident at St George Hospital, Sydney, NSW. Dr Rosen is a dermatologist at Liverpool Hospital, Sydney, NSW. Associate Professor Cains is from the University of NSW and leads the Liverpool Hospital HS clinic. References on request. • Open and closed comedones • Draining sinuses BOX 3. DIFFERENTIAL DIAGNOSES • Cutaneous Crohn’s disease • Simple abscess (usually solitary) • Recurrent staphylococcal folliculitis NEXT WEEK: Part 2 – Management and treatment of hidradenitis suppurativa.

Australian Doctor Australian Doctor 30th June 2017 | Page 26