A patient aged 29 years presents complaining of years of ‘boils’ on her groin. She has seen many physicians and tried many different topical and oral medications without improvement. On exam, extensive scarring, inflammatory nodules, and sinus tracts are noted in the groin.
Submit your diagnosis to see full explanation.
Hidradenitis suppurativa is a follicular-based inflammatory disorder, which most commonly appears in the genital or axillary regions but may appear in other regions with apocrine sweat glands.
Although once thought to be a disease of the apocrine glands themselves, it is now known that follicular occlusion is the primary event.
The initial finding is pruritus, followed by a painful papule or nodule. Inflammation and fibrosis follow the follicular occlusion and can lead to abscess formation and granulomas. Despite the fact that the individual lesions are transient, the rupturing of cysts causes spreading to the adjacent areas of apocrine skin.
Once a diagnosis is made, disease severity is classified by Hurley staging based on recurrence, presence of sinus tracts, and whether lesions are separate or connected.
One quarter of patients with hidradenitis suppurativa have a family history of the disease, although no HLA-associations have been found. Inguinal lesions are more common in females, after puberty, and in people of African descent.
There may be a hormonal association with hidradenitis suppurativa, as incidence increases with oral contraceptive use and during the premenstrual period. Hidradenitis suppurativa has also been associated with obesity and smoking.
There is no evidence that viral or fungal infections cause hidradenitis suppurativa. Plugging and occlusion of the hair follicle leads to cysts. When cysts rupture, adjacent follicles are susceptible to plugging from keratin and can form epithelial strands.
Deep sinus tracts may also form secondary to the continued foreign body inflammatory reaction to the ruptured cyst contents.
Locally, lesions in the inguinal and genitofemoral region can cause strictures, fistulas, and disfiguration of proximal structures such as the anus or urethra. Rarely, the chronic inflammation can predispose patients to squamous cell carcinoma.
The most common systemic complication of hidradenitis suppurativa is infection arising from fistulas and deep sinus tracts. Deep lesions that are manipulated can lead to rupture and dissemination, and may then cause bacteremia.
Hidradenitis suppurativa lesions are painful and may also have psychosocial impact on patients. The drainage can be malodorous and embarrassing, the fibrotic processes can leave permanent scarring, and the lesions can continue to recur despite treatment.
The most important components of management are treatment of the primary lesions and treatment and prevention of secondary issues such as infection and sinus tract formation.
In disease that is limited to isolated abscesses, systemic drugs and medical management can be sufficient. Topical clindamycin and intralesional corticosteroids may be useful. Systemic retinoids, biological agents, and hormonal therapy may be of benefit.
More extensive disease may require both medical and excisional treatments. With excision, clear margins are necessary to avoid recurrence of lesions.
Radical surgery may be indicated in hidradenitis suppurativa when there are coalescing lesions and chronic inflammation. Radiotherapy can help, but the risk to benefit ratio must be carefully considered.
Harina Vin is a medical student at Baylor College of Medicine.
Adam Rees, MD, is a graduate of the University of California Los Angeles School of Medicine and a resident in the Department of Dermatology at Baylor College of Medicine in Houston.
- Bolognia J, Jorizzo J, Schafffer J. 2012. “Chapter 38 – Folliculitis and Other Follicular Disorders.” Dermatology, 3rd ed. St. Louis, MO: Saunders/Elsevier. Print.
- Goldsmith L (ed). 2012. “Chapter 85 – Disorders of the Apocrine Sweat Glands.” Fitzpatrick’s Dermatology in General Medicine. New York: McGraw-Hill. Print.
- Zee, H. H., Laman, J. D., Boer, J. & Prens, E. P. Hidradenitis suppurativa: viewpoint on clinical phenotyping, pathogenesis and novel treatments. Exp. Dermatol. (2012). doi:10.1111/j.1600-0625.2012.01552.x