Hidradenitis suppurativa is a chronic and stubborn disease centred on inflammation of the large specialized sweat glands (apocrine glands) that are found mainly in the armpits and groins. These areas show a distinctive mixture of boil-like lumps, areas leaking pus, and scarring.
It is still not clear why the apocrine sweat glands are affected like this in some people, but mechanical blockage plays a part. As the secretions cannot escape, the tubes containing them may swell up and burst, or become infected.
Contributory factors include the following:
- Hormones are involved in the control of apocrine sweat glands and certainly play a part in the disease. Hidradenitis suppurativa affects women more often than men. It does not start before puberty or after the menopause. It may get better during pregnancy, but is often worse before menstrual periods. Some patients do well with hormone treatments (see below).
- Bacteria play a part too, but a variety of germs, and not just one special type, is found in the spots. It is not clear whether they cause the disease, or just flourish within it.
- There may be a link with acne.
- Hidradenitis suppurativa sometimes runs in families, and some patients or family members may also have had bad acne, or a chronic abscess at the base of the spine (a pilonidal sinus).
- The diagnosis is made from the appearances of the rash and by taking into account the areas of distribution. Your doctor may take swabs from the area to see which type of germ is present.
- Hidradenitis suppurativa usually persists for many years, but may disappear eventually. Treatment usually helps even though it cannot switch the hidradenitis off once and for all.
HidradenitisHidradenitis suppurativa can be itchy, but is usually painful, and the lumps hurt if they are pressed.
The severity of hidradenitis suppurativa varies from person to person. The main areas to be affected are the armpits, and the skin around the genitals - in the pubic area and in the groins. The skin around the back passage, on the upper buttocks and thighs, and below the breasts, can be affected too.
In these areas, the skin shows a variable mixture of blackheads, red lumps looking like boils, pus spots, cysts, and areas that constantly leak pus (sinuses). The abscesses can even burrow into nearby structures. As time goes by, more and more scarring appears.
There are many ways in which your doctor can help you with your hidradenitis suppurativa. In general terms, early hidradenitis suppurativa is usually treated medically, whereas hidradenitis suppurativa that has been going for a long time may need surgery.
If hidradenitis suppurativa suddenly becomes worse:
- This may be due to an infection with ordinary germs of the types that infect cuts and grazes; so antibiotics such as flucloxacillin may be used as a short course.
- Frequent episodes of this type, with proven bacterial infection, usually mean that you have a sinus or abscess (see treatments below).
- Antibiotics by mouth, taken long-term, help to suppress attacks. The ones that are used may be the same ones as for acne - such as tetracycline. Sometimes a combination of clindamycin and rifampicin is used. Some topical applications of antibiotics can be helpful.
- Vitamin A derived drugs such as acitretin and isotretinoin may help too, but have important side effects and are available only from dermatology departments.
- For women whose hidradenitis suppurativa flares before each period, tablets known as antiandrogens can be useful. The usual one is cyproterone acetate, 50 mg taken on days 5-15 of the menstrual cycle in conjunction with an oral contraceptive called Diane 35. Another antiandrogen that is more powerful is finasteride 5 mg.
- If the disease is severe, stronger drugs including oral corticosteroids may be used but all carry the risk causing of side effects.
- Recent studies suggest that using TNF-inbitors such as adalimumab or infliximab have some benefit in stopping the inflammation. However, the success rate is still low (~15% improvement) and these medications are very expensive (~$20,000 per year).
Treatment of scarred sinuses and abscesses
Persistent discharge or infection in the same site usually means that the medical treatments listed above will not work, and surgical operations - either to remove small areas of repeated inflammation, or wider procedures to take away all the diseased glands - are needed in some cases. In general, hidradenitis of the armpits does better with surgery than hidradenitis in other sites.
What you can do to help
- If you are too heavy, you will need to lose weight.
- As with many other diseases in skin folds, friction makes hidradenitis suppurativa worse, and should be avoided.
- You should wash with antiseptic soaps or bath additives.