Skin Disorders Guide

Diagnostic Hallmarks

1. Distribution: axillae and groin
2. Nonresponsiveness to antibiotic therapy
3. Chronic course with recurrence in the same sites

Clinical Presentation

The individual lesions of hidradenitis suppurativa arise as firm, lender, dome-shaped papules and nodules 1 to 3 cm in size. The larger lesions often become fluctuant and drain spontaneously. Pustule formation at the summit of the inflamed nodule is sometimes seen. Lesions are most commonly found in the groin and in the axillae the buttocks and breasts are occasionally involved. Individual lesions are easily confused with the lesions of furunculosis. Their distinctive location, multiple recurrences at the same site, the recovery of a panoply of organisms on culture, and the failure to respond promptly to antibiotic therapy are, however, helpful clues to the diagnosis of hidradenitis suppurativa.

The disease is considerably more common in women than In men. Blacks are affected more often than Caucasians. The obese are at greater risk for the disease than are those who are thin.

Course and Prognosis

Hidradenitis suppuraliva usually has its onset during late puberty and then continues sporadically throughout the next 10 to 20 years. There is considerable variation in severity from patient to patient. In some patients, only two or three small papules develop each year, whereas in others, new lesions appear and drain as rapidly as old ones resolve. disease activity often seems to be directly related to the degree of obesity.

Individual lesions, whether they drain spontaneously or not, heal slowly over a period of 10 to 30 days. Healing is allmost always accompanied by some scarring. In a few patients, recurrent scarring results in the development of lymphedema and contracture formation. On the other hand, scarring may also contribute to the apparent “burning out” of the disease over a period of many years.

Pathogenesis

Hidradenitis suppurativa appears to be an acne-like process of those pilosebaceous units to which apocrine sweat glands are attached. Such units are normally found only in the axilla and groin, but ectopic glands can be found around the breasts and on the buttocks.

Apocrine glands do not become active until hormonal stimulation begins during puberty. If at that time the outlet of one or more follicular units is blocked, the entire follicle becomes distended. Distention is then followed by rupture and extrusion of apocrine sweat and follicular bacteria into the surrounding tissue. This, in turn, results in a massive inflammatory response and the formation of a painful nodule. The reasons for blockage of the apocrine follicle are not known, but some possibilities include embryologic malformation of the apocrine duct, compression of the follicular outlet as a result of retention (miliaria), and bacterial infection of the ostium.

Therapy

Hidradenitis suppurativa is an extremely difficult disease to control. The first step in therapy is to improve those environmental factors that might cause follicular blockage. Attempts should be made to minimize both local heat buildup and sweat retention. The patient should be advised to avoid wearing constrictive clothing and to lose as much weight as is appropriate.

Second, patients having continuous problems should be treated with tetracycline or erythromycin for at least 2 or 3 months. These antibiotics are primarily used in the treatment of hidradenitis suppurativa, as in the treatment of acne, to reduce the numbers of normal follicular bacteria and to obtain a nonsteroidal anti-inflammatory effect. If long-term antibiotic therapy proves insufficient, the administration of birth control pills should be considered. An antiandrogen effect can also be obtained with oral administration of spironolactone, though data supporting its use in the treatment of hidradenitis suppurativa are anecdotal in nature.

Individual lesions can be can be injected intralesionally with depot-type steroids such as triamcinolone . Fluctuant lesions should be incised and drained prior to injection. In spite of all these therapies, activity of the disease often continues. In such instances, consideration should be given to excisional surgery. A strip of apocrine gland-bearing skin, several centimeters wide, is removed, and the defect is dosed primarily or is grafted. The former is preferred. The presence of draining lesions is not a contraindication to the performance of surgery, since the pus that is present is primarily due to noninfectious inflammation.

Finally, the oral administration of retinoids should be considered. About 50% of patients receiving 4 months of isotretinoin (Accutane) in doses similar to those used for acne obtain appreciable improvement, but relapse quickly occurs after the medication is discontinued.