Symptoms and Presentation
HS generally presents with chronic, suppurating, painful lesions in glandular regions of the body, including the armpits, groin and anal areas, or in areas where skin-to-skin friction develops, such as the inner thighs and buttocks or under breasts.1,2 The multiple skin manifestations include open comedones such as blackheads (often with 2 or more “heads”) and tender subcutaneous acneiform papules that may be reddish bumps containing pus (which tend to enlarge and rupture under the skin, causing painful itching and burning) or deeper, small lumps that remain dormant for years, and which may also become enlarged with inflammation and pus. Over time, sinus tracts or “tunnels” form between subcutaneous papules. These leaky wounds heal very slowly, producing ropelike fibrotic subcutaneous scars that often lead to disabling contractures of the affected limbs.1,2
No single treatment for HS is effective in eradicating disease or preventing progression, but early recognition and treatment are critical to preventing further progression to severe disease that can have an impact on quality of life.8 Therapeutic goals for stage 1 HS in young patients are to reduce pain and inflammation and prevent scarring and disease progression through multimodal management. Topical disinfectants are generally considered ineffective.4 Topical antibiotics are the therapy of choice for mild-to-moderate disease, with the introduction of oral antibiotics where topical formulations are inadequate.4
Once the disease has progressed, biologic disease modifying antirheumatic therapies, laser therapy, and surgery may have some benefit.8 Evidence supporting the use of intravenous infliximab in Hurley stage 2 and 3 HS has not been adequate enough to recommend it.9
Treatment of HS requires an aggressive multidisciplinary effort that involves antibiotic treatment, multimodal anti-inflammatory therapy and hormonal therapies, dietary and lifestyle modifications, and avoidance of physical trauma to the affected regions, which can lead to rupture of abscesses, along with early surgical unroofing and debridement. Additionally, because of the stigma and psychological distress, counseling for possible depression and to support coping skills is also recommended.3
HS is a chronic disease. One study reported an average disease duration of 19 years in 90% of the cohort.3
The estimated prevalence of HS varies from 0.05% to 4.1% because of the challenges of collecting data and the large number of undiagnosed cases.4,5 HS is a disease of young adults, generally appearing after puberty in the second and third decades, with a decreasing prevalence in older adults. The average age of onset is 23 years, and in young men, the disease can continue into old age.3 HS is rare in children, and when it does occur in childhood, it is often the result of widespread disease in a family with a history of HS. This occurs in an estimated 34% to 40% of cases 3
Women are disproportionately affected at 3 times the rate of men, and tend to have a milder disease course. African American and biracial ethnicity are also associated with higher prevalence.. 6 Although direct correlations have not been proven, cigarette smoking, obesity, and a range of comorbid conditions are often present in patients with HS.7
Hurley Disease Stages
HS is divided into 3 stages according to Hurley classifications3:
Stage 1: Early formation of single or multiple transient abscesses without development of scarring or sinus tracts
Stage 2: Recurrent disease characterized by the formation of multiple inflammatory lesions with some tunnel development and scarring
Stage 3: Chronic, active disease in which large areas of skin are infected with abscesses with significant scarring and tunneling between lesions
It is important to note that Hurley classifications provide static definitions of HS disease, but do not capture transitional changes as they occur.
In HS, many factors exert pressure on support structures of defective folliculopilosebaceous units to initiate an immune-driven inflammatory reaction that becomes chronic. The precipitating factors include the influence of multiple kinds of endogenous and exogenous hormones — and particularly circuiting androgens that are enhanced in many cases by dietary sources — which cause the folliculopilosebaceous units to become clogged and enlarged. Friction from skin-to-skin contact, or with clothing, as well as pressure and sweating contribute to rupture and leakage of pus from the lesions and further inflammatory response.3
The role of bacteria in HS is complex. Although bacteria have long been presumed to be the cause of HS, such a link has not been clearly demonstrated. It is highly likely that bacteria play a major role in relapse of HS and chronicity of the disease.3 Deep tissue studies implicating Gram-positive cocci and Gram-positive bacteria such as Staphylococcus aureus, coagulase-negative staphylococci, and Corynebacterium species, along with efficacy of certain antibiotics such as rifampicin, clindamycin, and tetracycline, support a microbial pathogenesis.3
Three main criteria must be met to make a diagnosis of HS, including the presence of3:
1. Typical primary lesions appearing as deep-seated painful nodules (blind boils) that do not respond to standard antibiotic treatment for boils caused by bacteria. The lesions are also marked by secondary manifestations of abscesses, tunnel-like draining sinus tracts, bridged scars, and “tombstone” open comedones (blackheads)
2. Lesions located in the typical regions, including the axillae; groin; genital, perineal, and perianal areas; buttocks; thighs; underneath the breasts; and in the armpits
3. Occurring in a chronic and recurrent pattern
Because of the many manifestations of HS, patients are seen by a variety of clinical specialists for diagnosis, resulting in frequent misdiagnosis and inappropriate treatment. The differential diagnosis for HS involves ruling out infections caused by bacterial conditions and fungi, tumors, and cysts. Diseases such as Crohn’s and psoriasis are often comorbid and need to be diagnosed separately.3,5
HS is commonly misdiagnosed as a follicular pyoderma, such as folliculitis, furuncles, or carbuncles, 3 as well as simple boils, and is mistreated with topical medications that allow disease to progress to a state of permanent disability.3
Impact of Smoking and Diet
Smoking is strongly associated with disease severity in HS, as nicotine exacerbates the primary mechanism of follicular plugging.3
Dietary sources can influence stimulation of androgen receptors that control growth. High insulin levels from carbohydrate-rich diets and whey, as well as insulin-like growth factor-1 levels that become elevated from milk casein activate androgen receptors to bind more frequently with androgen produced by the adrenals, ovaries, and testes, but also with exogenous androgens supplied by hormonal birth control methods and by precursor molecules in dairy products consumed.3
An area of current investigation is the theory that a natural “zero-dairy” diet that maintains low glycemic-load control may prevent future progression of HS and may even prevent the formation of new lesions.6
Complications in HS are common and serious.3 They include fistulae into the urethra or bladder, and rarely, into the rectum, and arthropathy. Infections such as cellulitis, lumbosacral epidural abscess, and sacral bacterial osteomyelitis are infrequent sequelae of both open and subdural lesions. The lymphatic system may become involved, producing lymphedema. Widespread genital edema is seen in both men and women, and squamous cell carcinoma occurs predominantly in men, affecting the perineum in late disease, with a poor prognosis if not detected early.
Other systemic complications resulting from the chronic inflammation include metabolic disorders, anemia and hypoproteinemia, and less commonly amyloidosis.
Pain and limited range from contractures occurs as plaques, and ropelike scars form near joints. One of the most pervasive complications is depression and suicidal ideation.3
In later stages, when treatment of HS with antibiotic therapies often fails to prevent progression to more severe disease, surgery becomes the last option for many patients. Incision and drainage may be used to reduce pain from abscesses, but this treatment is not effective in areas of solid inflammation and nodules.4 This may be accompanied by various other surgical techniques, including mini-unroofing using a biopsy punch, deroofing using scissors, electrosurgery, or laser treatment. 4,10 In more advanced cases of HS, classical wide excision and closure is used to remove affected tissue from large tunneled areas.4,11 Although surgery can prevent recurrence, it comes at a cost of surgical scarring and disfigurement.
Hidradenitis suppurativa (HS) — also known as “acne inversa” — is a common inflammatory skin disorder that generally affects young adults and sometimes children, and can result in significant pain and reduction in quality of life. With no current cure, it is imperative to expedite diagnosis and treatment to prevent further damage.
Compiled by Linda Peckel
- Mayo Clinic. Hidradenitis suppurativa symptoms. https://www.mayoclinic.org/diseases-conditions/hidradenitis-suppurativa/symptoms-causes/syc-20352306. August 23, 2017. Accessed December 12, 2017.
- Micheletti RG. Natural history, presentation, and diagnosis of hidradenitis suppurativa. Semin Cutan Med Surg. 2014;33:S51-S53.
- Margesson LJ, Danby FW. Hidradenitis suppurativa. Best Pract Res Clin Obstet Gynaecol. 2014;28:1013-1027.
- Saunte DML, Jemec GBE. Hidradenitis suppurativa: advances in diagnosis and treatment. JAMA. 2017;318:2019-2032.
- Jemec GB, Kimball AB. Hidradenitis suppurativa: epidemiology and scope of the problem. J Am Acad Dermatol. 2015;73:S4-S7.
- Danby FW. Diet in the prevention of hidradenitis suppurativa (acne inversa). J Am Acad Dermatol. 2015;73:S52-S54.
- Micheletti RG. Hidradenitis suppurativa: current views on epidemiology, pathogenesis, and pathophysiology. Semin Cutan Med Surg. 2014;33:S48-S50.
- Liy-Wong C, Pope E, Lara-Corrales I. Hidradenitis suppurativa in the pediatric population. J Am Acad Dermatol. 2015;73:S36-S41.
- Alhusayen R, Shear NH. Pharmacologic interventions for hidradenitis suppurativa: what does the evidence say? Am J Clin Dermatol. 2012;13:283-291.
- Danby FW, Hazen PG, Boer J. New and traditional surgical approaches to hidradenitis suppurativa. J Am Acad Dermatol. 2015;73:S62-S65.
- Martorell A, García-Martínez FJ, Jiménez-Gallo D, et al. An update on hidradenitis suppurativa (part I): epidemiology, clinical aspects, and definition of disease severity. Actas Dermosifiliogr. 2015;106:703-715.